browser close - Page 461

.htaccess change displayed url

- by breez

Hi, is there any way to get example.com/all-requests to go to example.com/forum/all-requests but still have the browser url show the former? (iow not just a simple forward call). Thanks!

explorer.exe opens slowly [closed]

- by d9k

explorer.exe opens veeeery slow when I press [Win+R] key or type "explorer ." in command prompt etc. But it opens with normal speed when I just click on the shortcut to any folder. When I click on the URL in IM like ICQ, already openned browser (firefox) takes too long to process link too. I have this problem for some months and I'm very tired of this. OS: WinXP SP3.

Read the article

app-engine-rest-server to raise KeyError("name %s already used" % model_name)

- by fx

I'm playing with the project appengine-rest-server to create the REST webservices for all the existing models. I got a strange error, the first time I query the browser: http://localhost:8080/rest/metadata/user, it gives me the result: <xs:schema> - <xs:element name="user"> - <xs:complexType> - <xs:sequence> <xs:element maxOccurs="1" minOccurs="0" name="key" type="xs:normalizedString"/> <xs:element maxOccurs="1" minOccurs="0" name="surname" type="xs:string"/> <xs:element maxOccurs="1" minOccurs="0" name="firstname" type="xs:string"/> <xs:element maxOccurs="1" minOccurs="0" name="ages" type="xs:long"/> <xs:element maxOccurs="1" minOccurs="0" name="sex" type="xs:boolean"/> <xs:element maxOccurs="1" minOccurs="0" name="updatedDate" type="xs:dateTime"/> <xs:element maxOccurs="1" minOccurs="0" name="createdDate" type="xs:dateTime"/> </xs:sequence> </xs:complexType> </xs:element> </xs:schema> But refreshing the page, gives me this error: Traceback (most recent call last): File "/Users/foo/Documents/AppEngine/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 3185, in _HandleRequest self._Dispatch(dispatcher, self.rfile, outfile, env_dict) File "/Users/foo/Documents/AppEngine/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 3128, in _Dispatch base_env_dict=env_dict) File "/Users/foo/Documents/AppEngine/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 515, in Dispatch base_env_dict=base_env_dict) File "/Users/foo/Documents/AppEngine/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 2387, in Dispatch self._module_dict) File "/Users/foo/Documents/AppEngine/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 2297, in ExecuteCGI reset_modules = exec_script(handler_path, cgi_path, hook) File "/Users/foo/Documents/AppEngine/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 2195, in ExecuteOrImportScript script_module.main() File "/Users/foo/Documents/AppEngine/helloworld/main.py", line 48, in main rest.Dispatcher.add_models({"user": UserModel}) File "/Users/foo/Documents/AppEngine/helloworld/rest/__init__.py", line 845, in add_models cls.add_model(model_name, model_type) File "/Users/foo/Documents/AppEngine/helloworld/rest/__init__.py", line 863, in add_model raise KeyError("name %s already used" % model_name) KeyError: 'name user already used' Can someone give me the explanation on why it happens? Restarting the server, run on the browser again I get the xml result, but refreshing causes the error. Is it a bug in the appengine-rest-server application or it is in my code? My helloworld application is available for download here.

Read the article

Using closes sql connection brought over by a function

- by iefpw

Would this using close this _connection? using(SqlConnection _connection = Class1.GetSqlConnection()) { //code inside the connection } //connection should be closed/ended? I'm just wondering because GetSqlConnection() is a static function of Class1 and the whole connection might not be closed because it is calling outside class' static function instead of straight? using(SqlConnection _connection = new SqlConnection(_connectionString) { //code inside the connection }

Read the article

Storing and displaying unicode string (??????) using PHP and MySQL

- by Anirudh Goel

I have to store hindi text in a MySQL database, fetch it using a PHP script and display it on a webpage. I did the following: I created a database and set its encoding to UTF-8 and also the collation to utf8_bin. I added a varchar field in the table and set it to accept UTF-8 text in the charset property. Then I set about adding data to it. Here I had to copy data from an existing site. The hindi text looks like this: ????????:05:30 I directly copied this text into my database and used the PHP code echo(utf8_encode($string)) to display the data. Upon doing so the browser showed me "??????". When I inserted the UTF equivalent of the text by going to "view source" in the browser, however, ???????? translates into सूर्योदय. If I enter and store सूर्योदय in the database, it converts perfectly. So what I want to know is how I can directly store ???????? into my database and fetch it and display it in my webpage using PHP. Also, can anyone help me understand if there's a script which when I type in ????????, gives me सूर्योदय? Solution Found I wrote the following sample script which worked for me. Hope it helps someone else too <html> <head> <title>Hindi</title></head> <body> <?php include("connection.php"); //simple connection setting $result = mysql_query("SET NAMES utf8"); //the main trick $cmd = "select * from hindi"; $result = mysql_query($cmd); while ($myrow = mysql_fetch_row($result)) { echo ($myrow[0]); } ?> </body> </html> The dump for my database storing hindi utf strings is CREATE TABLE `hindi` ( `data` varchar(1000) character set utf8 collate utf8_bin default NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `hindi` VALUES ('????????'); Now my question is, how did it work without specifying "META" or header info? Thanks!

Read the article

Do static / relative divs accept height in %

- by Crimson

I have a div which needs to be positioned statically / relatively. When it has both height and width defined in %, the browser (FF) ignores the height set and renders a very small div. However, when I set the height in px (approximately same calculated value), it works smoothly. The width defined in % works perfectly. I need the height to be defined in % as well - due to resolution / scaling issues.

Read the article

Capturing and Transforming ASP.NET Output with Response.Filter

- by Rick Strahl

During one of my Handlers and Modules session at DevConnections this week one of the attendees asked a question that I didn’t have an immediate answer for. Basically he wanted to capture response output completely and then apply some filtering to the output – effectively injecting some additional content into the page AFTER the page had completely rendered. Specifically the output should be captured from anywhere – not just a page and have this code injected into the page. Some time ago I posted some code that allows you to capture ASP.NET Page output by overriding the Render() method, capturing the HtmlTextWriter() and reading its content, modifying the rendered data as text then writing it back out. I’ve actually used this approach on a few occasions and it works fine for ASP.NET pages. But this obviously won’t work outside of the Page class environment and it’s not really generic – you have to create a custom page class in order to handle the output capture. [updated 11/16/2009 – updated ResponseFilterStream implementation and a few additional notes based on comments] Enter Response.Filter However, ASP.NET includes a Response.Filter which can be used – well to filter output. Basically Response.Filter is a stream through which the OutputStream is piped back to the Web Server (indirectly). As content is written into the Response object, the filter stream receives the appropriate Stream commands like Write, Flush and Close as well as read operations although for a Response.Filter that’s uncommon to be hit. The Response.Filter can be programmatically replaced at runtime which allows you to effectively intercept all output generation that runs through ASP.NET. A common Example: Dynamic GZip Encoding A rather common use of Response.Filter hooking up code based, dynamic GZip compression for requests which is dead simple by applying a GZipStream (or DeflateStream) to Response.Filter. The following generic routines can be used very easily to detect GZip capability of the client and compress response output with a single line of code and a couple of library helper routines: WebUtils.GZipEncodePage(); which is handled with a few lines of reusable code and a couple of static helper methods: /// <summary> ///Sets up the current page or handler to use GZip through a Response.Filter ///IMPORTANT: ///You have to call this method before any output is generated! /// </summary> public static void GZipEncodePage() { HttpResponse Response = HttpContext.Current.Response; if(IsGZipSupported()) { stringAcceptEncoding = HttpContext.Current.Request.Headers["Accept-Encoding"]; if(AcceptEncoding.Contains("deflate")) { Response.Filter = newSystem.IO.Compression.DeflateStream(Response.Filter, System.IO.Compression.CompressionMode.Compress); Response.AppendHeader("Content-Encoding", "deflate"); } else { Response.Filter = newSystem.IO.Compression.GZipStream(Response.Filter, System.IO.Compression.CompressionMode.Compress); Response.AppendHeader("Content-Encoding", "gzip"); } } // Allow proxy servers to cache encoded and unencoded versions separately Response.AppendHeader("Vary", "Content-Encoding"); } /// <summary> /// Determines if GZip is supported /// </summary> /// <returns></returns> public static bool IsGZipSupported() { string AcceptEncoding = HttpContext.Current.Request.Headers["Accept-Encoding"]; if (!string.IsNullOrEmpty(AcceptEncoding) && (AcceptEncoding.Contains("gzip") || AcceptEncoding.Contains("deflate"))) return true; return false; } GZipStream and DeflateStream are streams that are assigned to Response.Filter and by doing so apply the appropriate compression on the active Response. Response.Filter content is chunked So to implement a Response.Filter effectively requires only that you implement a custom stream and handle the Write() method to capture Response output as it’s written. At first blush this seems very simple – you capture the output in Write, transform it and write out the transformed content in one pass. And that indeed works for small amounts of content. But you see, the problem is that output is written in small buffer chunks (a little less than 16k it appears) rather than just a single Write() statement into the stream, which makes perfect sense for ASP.NET to stream data back to IIS in smaller chunks to minimize memory usage en route. Unfortunately this also makes it a more difficult to implement any filtering routines since you don’t directly get access to all of the response content which is problematic especially if those filtering routines require you to look at the ENTIRE response in order to transform or capture the output as is needed for the solution the gentleman in my session asked for. So in order to address this a slightly different approach is required that basically captures all the Write() buffers passed into a cached stream and then making the stream available only when it’s complete and ready to be flushed. As I was thinking about the implementation I also started thinking about the few instances when I’ve used Response.Filter implementations. Each time I had to create a new Stream subclass and create my custom functionality but in the end each implementation did the same thing – capturing output and transforming it. I thought there should be an easier way to do this by creating a re-usable Stream class that can handle stream transformations that are common to Response.Filter implementations. Creating a semi-generic Response Filter Stream Class What I ended up with is a ResponseFilterStream class that provides a handful of Events that allow you to capture and/or transform Response content. The class implements a subclass of Stream and then overrides Write() and Flush() to handle capturing and transformation operations. By exposing events it’s easy to hook up capture or transformation operations via single focused methods. ResponseFilterStream exposes the following events: CaptureStream, CaptureString Captures the output only and provides either a MemoryStream or String with the final page output. Capture is hooked to the Flush() operation of the stream. TransformStream, TransformString Allows you to transform the complete response output with events that receive a MemoryStream or String respectively and can you modify the output then return it back as a return value. The transformed output is then written back out in a single chunk to the response output stream. These events capture all output internally first then write the entire buffer into the response. TransformWrite, TransformWriteString Allows you to transform the Response data as it is written in its original chunk size in the Stream’s Write() method. Unlike TransformStream/TransformString which operate on the complete output, these events only see the current chunk of data written. This is more efficient as there’s no caching involved, but can cause problems due to searched content splitting over multiple chunks. Using this implementation, creating a custom Response.Filter transformation becomes as simple as the following code. To hook up the Response.Filter using the MemoryStream version event: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformStream += filter_TransformStream; Response.Filter = filter; and the event handler to do the transformation: MemoryStream filter_TransformStream(MemoryStream ms) { Encoding encoding = HttpContext.Current.Response.ContentEncoding; string output = encoding.GetString(ms.ToArray()); output = FixPaths(output); ms = new MemoryStream(output.Length); byte[] buffer = encoding.GetBytes(output); ms.Write(buffer,0,buffer.Length); return ms; } private string FixPaths(string output) { string path = HttpContext.Current.Request.ApplicationPath; // override root path wonkiness if (path == "/") path = ""; output = output.Replace("\"~/", "\"" + path + "/").Replace("'~/", "'" + path + "/"); return output; } The idea of the event handler is that you can do whatever you want to the stream and return back a stream – either the same one that’s been modified or a brand new one – which is then sent back to as the final response. The above code can be simplified even more by using the string version events which handle the stream to string conversions for you: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; and the event handler to do the transformation calling the same FixPaths method shown above: string filter_TransformString(string output) { return FixPaths(output); } The events for capturing output and capturing and transforming chunks work in a very similar way. By using events to handle the transformations ResponseFilterStream becomes a reusable component and we don’t have to create a new stream class or subclass an existing Stream based classed. By the way, the example used here is kind of a cool trick which transforms “~/” expressions inside of the final generated HTML output – even in plain HTML controls not HTML controls – and transforms them into the appropriate application relative path in the same way that ResolveUrl would do. So you can write plain old HTML like this: <a href=”~/default.aspx”>Home</a> and have it turned into: <a href=”/myVirtual/default.aspx”>Home</a> without having to use an ASP.NET control like Hyperlink or Image or having to constantly use: <img src=”<%= ResolveUrl(“~/images/home.gif”) %>” /> in MVC applications (which frankly is one of the most annoying things about MVC especially given the path hell that extension-less and endpoint-less URLs impose). I can’t take credit for this idea. While discussing the Response.Filter issues on Twitter a hint from Dylan Beattie who pointed me at one of his examples which does something similar. I thought the idea was cool enough to use an example for future demos of Response.Filter functionality in ASP.NET next I time I do the Modules and Handlers talk (which was great fun BTW). How practical this is is debatable however since there’s definitely some overhead to using a Response.Filter in general and especially on one that caches the output and the re-writes it later. Make sure to test for performance anytime you use Response.Filter hookup and make sure it' doesn’t end up killing perf on you. You’ve been warned :-}. How does ResponseFilterStream work? The big win of this implementation IMHO is that it’s a reusable component – so for implementation there’s no new class, no subclassing – you simply attach to an event to implement an event handler method with a straight forward signature to retrieve the stream or string you’re interested in. The implementation is based on a subclass of Stream as is required in order to handle the Response.Filter requirements. What’s different than other implementations I’ve seen in various places is that it supports capturing output as a whole to allow retrieving the full response output for capture or modification. The exception are the TransformWrite and TransformWrite events which operate only active chunk of data written by the Response. For captured output, the Write() method captures output into an internal MemoryStream that is cached until writing is complete. So Write() is called when ASP.NET writes to the Response stream, but the filter doesn’t pass on the Write immediately to the filter’s internal stream. The data is cached and only when the Flush() method is called to finalize the Stream’s output do we actually send the cached stream off for transformation (if the events are hooked up) and THEN finally write out the returned content in one big chunk. Here’s the implementation of ResponseFilterStream: /// <summary> /// A semi-generic Stream implementation for Response.Filter with /// an event interface for handling Content transformations via /// Stream or String. /// <remarks> /// Use with care for large output as this implementation copies /// the output into a memory stream and so increases memory usage. /// </remarks> /// </summary> public class ResponseFilterStream : Stream { /// <summary> /// The original stream /// </summary> Stream _stream; /// <summary> /// Current position in the original stream /// </summary> long _position; /// <summary> /// Stream that original content is read into /// and then passed to TransformStream function /// </summary> MemoryStream _cacheStream = new MemoryStream(5000); /// <summary> /// Internal pointer that that keeps track of the size /// of the cacheStream /// </summary> int _cachePointer = 0; /// <summary> /// /// </summary> /// <param name="responseStream"></param> public ResponseFilterStream(Stream responseStream) { _stream = responseStream; } /// <summary> /// Determines whether the stream is captured /// </summary> private bool IsCaptured { get { if (CaptureStream != null || CaptureString != null || TransformStream != null || TransformString != null) return true; return false; } } /// <summary> /// Determines whether the Write method is outputting data immediately /// or delaying output until Flush() is fired. /// </summary> private bool IsOutputDelayed { get { if (TransformStream != null || TransformString != null) return true; return false; } } /// <summary> /// Event that captures Response output and makes it available /// as a MemoryStream instance. Output is captured but won't /// affect Response output. /// </summary> public event Action<MemoryStream> CaptureStream; /// <summary> /// Event that captures Response output and makes it available /// as a string. Output is captured but won't affect Response output. /// </summary> public event Action<string> CaptureString; /// <summary> /// Event that allows you transform the stream as each chunk of /// the output is written in the Write() operation of the stream. /// This means that that it's possible/likely that the input /// buffer will not contain the full response output but only /// one of potentially many chunks. /// /// This event is called as part of the filter stream's Write() /// operation. /// </summary> public event Func<byte[], byte[]> TransformWrite; /// <summary> /// Event that allows you to transform the response stream as /// each chunk of bytep[] output is written during the stream's write /// operation. This means it's possibly/likely that the string /// passed to the handler only contains a portion of the full /// output. Typical buffer chunks are around 16k a piece. /// /// This event is called as part of the stream's Write operation. /// </summary> public event Func<string, string> TransformWriteString; /// <summary> /// This event allows capturing and transformation of the entire /// output stream by caching all write operations and delaying final /// response output until Flush() is called on the stream. /// </summary> public event Func<MemoryStream, MemoryStream> TransformStream; /// <summary> /// Event that can be hooked up to handle Response.Filter /// Transformation. Passed a string that you can modify and /// return back as a return value. The modified content /// will become the final output. /// </summary> public event Func<string, string> TransformString; protected virtual void OnCaptureStream(MemoryStream ms) { if (CaptureStream != null) CaptureStream(ms); } private void OnCaptureStringInternal(MemoryStream ms) { if (CaptureString != null) { string content = HttpContext.Current.Response.ContentEncoding.GetString(ms.ToArray()); OnCaptureString(content); } } protected virtual void OnCaptureString(string output) { if (CaptureString != null) CaptureString(output); } protected virtual byte[] OnTransformWrite(byte[] buffer) { if (TransformWrite != null) return TransformWrite(buffer); return buffer; } private byte[] OnTransformWriteStringInternal(byte[] buffer) { Encoding encoding = HttpContext.Current.Response.ContentEncoding; string output = OnTransformWriteString(encoding.GetString(buffer)); return encoding.GetBytes(output); } private string OnTransformWriteString(string value) { if (TransformWriteString != null) return TransformWriteString(value); return value; } protected virtual MemoryStream OnTransformCompleteStream(MemoryStream ms) { if (TransformStream != null) return TransformStream(ms); return ms; } /// <summary> /// Allows transforming of strings /// /// Note this handler is internal and not meant to be overridden /// as the TransformString Event has to be hooked up in order /// for this handler to even fire to avoid the overhead of string /// conversion on every pass through. /// </summary> /// <param name="responseText"></param> /// <returns></returns> private string OnTransformCompleteString(string responseText) { if (TransformString != null) TransformString(responseText); return responseText; } /// <summary> /// Wrapper method form OnTransformString that handles /// stream to string and vice versa conversions /// </summary> /// <param name="ms"></param> /// <returns></returns> internal MemoryStream OnTransformCompleteStringInternal(MemoryStream ms) { if (TransformString == null) return ms; //string content = ms.GetAsString(); string content = HttpContext.Current.Response.ContentEncoding.GetString(ms.ToArray()); content = TransformString(content); byte[] buffer = HttpContext.Current.Response.ContentEncoding.GetBytes(content); ms = new MemoryStream(); ms.Write(buffer, 0, buffer.Length); //ms.WriteString(content); return ms; } /// <summary> /// /// </summary> public override bool CanRead { get { return true; } } public override bool CanSeek { get { return true; } } /// <summary> /// /// </summary> public override bool CanWrite { get { return true; } } /// <summary> /// /// </summary> public override long Length { get { return 0; } } /// <summary> /// /// </summary> public override long Position { get { return _position; } set { _position = value; } } /// <summary> /// /// </summary> /// <param name="offset"></param> /// <param name="direction"></param> /// <returns></returns> public override long Seek(long offset, System.IO.SeekOrigin direction) { return _stream.Seek(offset, direction); } /// <summary> /// /// </summary> /// <param name="length"></param> public override void SetLength(long length) { _stream.SetLength(length); } /// <summary> /// /// </summary> public override void Close() { _stream.Close(); } /// <summary> /// Override flush by writing out the cached stream data /// </summary> public override void Flush() { if (IsCaptured && _cacheStream.Length > 0) { // Check for transform implementations _cacheStream = OnTransformCompleteStream(_cacheStream); _cacheStream = OnTransformCompleteStringInternal(_cacheStream); OnCaptureStream(_cacheStream); OnCaptureStringInternal(_cacheStream); // write the stream back out if output was delayed if (IsOutputDelayed) _stream.Write(_cacheStream.ToArray(), 0, (int)_cacheStream.Length); // Clear the cache once we've written it out _cacheStream.SetLength(0); } // default flush behavior _stream.Flush(); } /// <summary> /// /// </summary> /// <param name="buffer"></param> /// <param name="offset"></param> /// <param name="count"></param> /// <returns></returns> public override int Read(byte[] buffer, int offset, int count) { return _stream.Read(buffer, offset, count); } /// <summary> /// Overriden to capture output written by ASP.NET and captured /// into a cached stream that is written out later when Flush() /// is called. /// </summary> /// <param name="buffer"></param> /// <param name="offset"></param> /// <param name="count"></param> public override void Write(byte[] buffer, int offset, int count) { if ( IsCaptured ) { // copy to holding buffer only - we'll write out later _cacheStream.Write(buffer, 0, count); _cachePointer += count; } // just transform this buffer if (TransformWrite != null) buffer = OnTransformWrite(buffer); if (TransformWriteString != null) buffer = OnTransformWriteStringInternal(buffer); if (!IsOutputDelayed) _stream.Write(buffer, offset, buffer.Length); } } The key features are the events and corresponding OnXXX methods that handle the event hookups, and the Write() and Flush() methods of the stream implementation. All the rest of the members tend to be plain jane passthrough stream implementation code without much consequence. I do love the way Action<t> and Func<T> make it so easy to create the event signatures for the various events – sweet. A few Things to consider Performance Response.Filter is not great for performance in general as it adds another layer of indirection to the ASP.NET output pipeline, and this implementation in particular adds a memory hit as it basically duplicates the response output into the cached memory stream which is necessary since you may have to look at the entire response. If you have large pages in particular this can cause potentially serious memory pressure in your server application. So be careful of wholesale adoption of this (or other) Response.Filters. Make sure to do some performance testing to ensure it’s not killing your app’s performance. Response.Filter works everywhere A few questions came up in comments and discussion as to capturing ALL output hitting the site and – yes you can definitely do that by assigning a Response.Filter inside of a module. If you do this however you’ll want to be very careful and decide which content you actually want to capture especially in IIS 7 which passes ALL content – including static images/CSS etc. through the ASP.NET pipeline. So it is important to filter only on what you’re looking for – like the page extension or maybe more effectively the Response.ContentType. Response.Filter Chaining Originally I thought that filter chaining doesn’t work at all due to a bug in the stream implementation code. But it’s quite possible to assign multiple filters to the Response.Filter property. So the following actually works to both compress the output and apply the transformed content: WebUtils.GZipEncodePage(); ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; However the following does not work resulting in invalid content encoding errors: ResponseFilterStream filter = new ResponseFilterStream(Response.Filter); filter.TransformString += filter_TransformString; Response.Filter = filter; WebUtils.GZipEncodePage(); In other words multiple Response filters can work together but it depends entirely on the implementation whether they can be chained or in which order they can be chained. In this case running the GZip/Deflate stream filters apparently relies on the original content length of the output and chokes when the content is modified. But if attaching the compression first it works fine as unintuitive as that may seem. Resources Download example code Capture Output from ASP.NET Pages © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET

Read the article

Service Discovery in WCF 4.0 – Part 1

- by Shaun

When designing a service oriented architecture (SOA) system, there will be a lot of services with many service contracts, endpoints and behaviors. Besides the client calling the service, in a large distributed system a service may invoke other services. In this case, one service might need to know the endpoints it invokes. This might not be a problem in a small system. But when you have more than 10 services this might be a problem. For example in my current product, there are around 10 services, such as the user authentication service, UI integration service, location service, license service, device monitor service, event monitor service, schedule job service, accounting service, player management service, etc.. Benefit of Discovery Service Since almost all my services need to invoke at least one other service. This would be a difficult task to make sure all services endpoints are configured correctly in every service. And furthermore, it would be a nightmare when a service changed its endpoint at runtime. Hence, we need a discovery service to remove the dependency (configuration dependency). A discovery service plays as a service dictionary which stores the relationship between the contracts and the endpoints for every service. By using the discovery service, when service X wants to invoke service Y, it just need to ask the discovery service where is service Y, then the discovery service will return all proper endpoints of service Y, then service X can use the endpoint to send the request to service Y. And when some services changed their endpoint address, all need to do is to update its records in the discovery service then all others will know its new endpoint. In WCF 4.0 Discovery it supports both managed proxy discovery mode and ad-hoc discovery mode. In ad-hoc mode there is no standalone discovery service. When a client wanted to invoke a service, it will broadcast an message (normally in UDP protocol) to the entire network with the service match criteria. All services which enabled the discovery behavior will receive this message and only those matched services will send their endpoint back to the client. The managed proxy discovery service works as I described above. In this post I will only cover the managed proxy mode, where there’s a discovery service. For more information about the ad-hoc mode please refer to the MSDN. Service Announcement and Probe The main functionality of discovery service should be return the proper endpoint addresses back to the service who is looking for. In most cases the consume service (as a client) will send the contract which it wanted to request to the discovery service. And then the discovery service will find the endpoint and respond. Sometimes the contract and endpoint are not enough. It also contains versioning, extensions attributes. This post I will only cover the case includes contract and endpoint. When a client (or sometimes a service who need to invoke another service) need to connect to a target service, it will firstly request the discovery service through the “Probe” method with the criteria. Basically the criteria contains the contract type name of the target service. Then the discovery service will search its endpoint repository by the criteria. The repository might be a database, a distributed cache or a flat XML file. If it matches, the discovery service will grab the endpoint information (it’s called discovery endpoint metadata in WCF) and send back. And this is called “Probe”. Finally the client received the discovery endpoint metadata and will use the endpoint to connect to the target service. Besides the probe, discovery service should take the responsible to know there is a new service available when it goes online, as well as stopped when it goes offline. This feature is named “Announcement”. When a service started and stopped, it will announce to the discovery service. So the basic functionality of a discovery service should includes: 1, An endpoint which receive the service online message, and add the service endpoint information in the discovery repository. 2, An endpoint which receive the service offline message, and remove the service endpoint information from the discovery repository. 3, An endpoint which receive the client probe message, and return the matches service endpoints, and return the discovery endpoint metadata. WCF 4.0 discovery service just covers all these features in it's infrastructure classes. Discovery Service in WCF 4.0 WCF 4.0 introduced a new assembly named System.ServiceModel.Discovery which has all necessary classes and interfaces to build a WS-Discovery compliant discovery service. It supports ad-hoc and managed proxy modes. For the case mentioned in this post, what we need to build is a standalone discovery service, which is the managed proxy discovery service mode. To build a managed discovery service in WCF 4.0 just create a new class inherits from the abstract class System.ServiceModel.Discovery.DiscoveryProxy. This class implemented and abstracted the procedures of service announcement and probe. And it exposes 8 abstract methods where we can implement our own endpoint register, unregister and find logic. These 8 methods are asynchronized, which means all invokes to the discovery service are asynchronously, for better service capability and performance. 1, OnBeginOnlineAnnouncement, OnEndOnlineAnnouncement: Invoked when a service sent the online announcement message. We need to add the endpoint information to the repository in this method. 2, OnBeginOfflineAnnouncement, OnEndOfflineAnnouncement: Invoked when a service sent the offline announcement message. We need to remove the endpoint information from the repository in this method. 3, OnBeginFind, OnEndFind: Invoked when a client sent the probe message that want to find the service endpoint information. We need to look for the proper endpoints by matching the client’s criteria through the repository in this method. 4, OnBeginResolve, OnEndResolve: Invoked then a client sent the resolve message. Different from the find method, when using resolve method the discovery service will return the exactly one service endpoint metadata to the client. In our example we will NOT implement this method. Let’s create our own discovery service, inherit the base System.ServiceModel.Discovery.DiscoveryProxy. We also need to specify the service behavior in this class. Since the build-in discovery service host class only support the singleton mode, we must set its instance context mode to single. 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Text; 5: using System.ServiceModel.Discovery; 6: using System.ServiceModel; 7: 8: namespace Phare.Service 9: { 10: [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple)] 11: public class ManagedProxyDiscoveryService : DiscoveryProxy 12: { 13: protected override IAsyncResult OnBeginFind(FindRequestContext findRequestContext, AsyncCallback callback, object state) 14: { 15: throw new NotImplementedException(); 16: } 17: 18: protected override IAsyncResult OnBeginOfflineAnnouncement(DiscoveryMessageSequence messageSequence, EndpointDiscoveryMetadata endpointDiscoveryMetadata, AsyncCallback callback, object state) 19: { 20: throw new NotImplementedException(); 21: } 22: 23: protected override IAsyncResult OnBeginOnlineAnnouncement(DiscoveryMessageSequence messageSequence, EndpointDiscoveryMetadata endpointDiscoveryMetadata, AsyncCallback callback, object state) 24: { 25: throw new NotImplementedException(); 26: } 27: 28: protected override IAsyncResult OnBeginResolve(ResolveCriteria resolveCriteria, AsyncCallback callback, object state) 29: { 30: throw new NotImplementedException(); 31: } 32: 33: protected override void OnEndFind(IAsyncResult result) 34: { 35: throw new NotImplementedException(); 36: } 37: 38: protected override void OnEndOfflineAnnouncement(IAsyncResult result) 39: { 40: throw new NotImplementedException(); 41: } 42: 43: protected override void OnEndOnlineAnnouncement(IAsyncResult result) 44: { 45: throw new NotImplementedException(); 46: } 47: 48: protected override EndpointDiscoveryMetadata OnEndResolve(IAsyncResult result) 49: { 50: throw new NotImplementedException(); 51: } 52: } 53: } Then let’s implement the online, offline and find methods one by one. WCF discovery service gives us full flexibility to implement the endpoint add, remove and find logic. For the demo purpose we will use an internal dictionary to store the services’ endpoint metadata. In the next post we will see how to serialize and store these information in database. Define a concurrent dictionary inside the service class since our it will be used in the multiple threads scenario. 1: [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple)] 2: public class ManagedProxyDiscoveryService : DiscoveryProxy 3: { 4: private ConcurrentDictionary<EndpointAddress, EndpointDiscoveryMetadata> _services; 5: 6: public ManagedProxyDiscoveryService() 7: { 8: _services = new ConcurrentDictionary<EndpointAddress, EndpointDiscoveryMetadata>(); 9: } 10: } Then we can simply implement the logic of service online and offline. 1: protected override IAsyncResult OnBeginOnlineAnnouncement(DiscoveryMessageSequence messageSequence, EndpointDiscoveryMetadata endpointDiscoveryMetadata, AsyncCallback callback, object state) 2: { 3: _services.AddOrUpdate(endpointDiscoveryMetadata.Address, endpointDiscoveryMetadata, (key, value) => endpointDiscoveryMetadata); 4: return new OnOnlineAnnouncementAsyncResult(callback, state); 5: } 6: 7: protected override void OnEndOnlineAnnouncement(IAsyncResult result) 8: { 9: OnOnlineAnnouncementAsyncResult.End(result); 10: } 11: 12: protected override IAsyncResult OnBeginOfflineAnnouncement(DiscoveryMessageSequence messageSequence, EndpointDiscoveryMetadata endpointDiscoveryMetadata, AsyncCallback callback, object state) 13: { 14: EndpointDiscoveryMetadata endpoint = null; 15: _services.TryRemove(endpointDiscoveryMetadata.Address, out endpoint); 16: return new OnOfflineAnnouncementAsyncResult(callback, state); 17: } 18: 19: protected override void OnEndOfflineAnnouncement(IAsyncResult result) 20: { 21: OnOfflineAnnouncementAsyncResult.End(result); 22: } Regards the find method, the parameter FindRequestContext.Criteria has a method named IsMatch, which can be use for us to evaluate which service metadata is satisfied with the criteria. So the implementation of find method would be like this. 1: protected override IAsyncResult OnBeginFind(FindRequestContext findRequestContext, AsyncCallback callback, object state) 2: { 3: _services.Where(s => findRequestContext.Criteria.IsMatch(s.Value)) 4: .Select(s => s.Value) 5: .All(meta => 6: { 7: findRequestContext.AddMatchingEndpoint(meta); 8: return true; 9: }); 10: return new OnFindAsyncResult(callback, state); 11: } 12: 13: protected override void OnEndFind(IAsyncResult result) 14: { 15: OnFindAsyncResult.End(result); 16: } As you can see, we checked all endpoints metadata in repository by invoking the IsMatch method. Then add all proper endpoints metadata into the parameter. Finally since all these methods are asynchronized we need some AsyncResult classes as well. Below are the base class and the inherited classes used in previous methods. 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Text; 5: using System.Threading; 6: 7: namespace Phare.Service 8: { 9: abstract internal class AsyncResult : IAsyncResult 10: { 11: AsyncCallback callback; 12: bool completedSynchronously; 13: bool endCalled; 14: Exception exception; 15: bool isCompleted; 16: ManualResetEvent manualResetEvent; 17: object state; 18: object thisLock; 19: 20: protected AsyncResult(AsyncCallback callback, object state) 21: { 22: this.callback = callback; 23: this.state = state; 24: this.thisLock = new object(); 25: } 26: 27: public object AsyncState 28: { 29: get 30: { 31: return state; 32: } 33: } 34: 35: public WaitHandle AsyncWaitHandle 36: { 37: get 38: { 39: if (manualResetEvent != null) 40: { 41: return manualResetEvent; 42: } 43: lock (ThisLock) 44: { 45: if (manualResetEvent == null) 46: { 47: manualResetEvent = new ManualResetEvent(isCompleted); 48: } 49: } 50: return manualResetEvent; 51: } 52: } 53: 54: public bool CompletedSynchronously 55: { 56: get 57: { 58: return completedSynchronously; 59: } 60: } 61: 62: public bool IsCompleted 63: { 64: get 65: { 66: return isCompleted; 67: } 68: } 69: 70: object ThisLock 71: { 72: get 73: { 74: return this.thisLock; 75: } 76: } 77: 78: protected static TAsyncResult End<TAsyncResult>(IAsyncResult result) 79: where TAsyncResult : AsyncResult 80: { 81: if (result == null) 82: { 83: throw new ArgumentNullException("result"); 84: } 85: 86: TAsyncResult asyncResult = result as TAsyncResult; 87: 88: if (asyncResult == null) 89: { 90: throw new ArgumentException("Invalid async result.", "result"); 91: } 92: 93: if (asyncResult.endCalled) 94: { 95: throw new InvalidOperationException("Async object already ended."); 96: } 97: 98: asyncResult.endCalled = true; 99: 100: if (!asyncResult.isCompleted) 101: { 102: asyncResult.AsyncWaitHandle.WaitOne(); 103: } 104: 105: if (asyncResult.manualResetEvent != null) 106: { 107: asyncResult.manualResetEvent.Close(); 108: } 109: 110: if (asyncResult.exception != null) 111: { 112: throw asyncResult.exception; 113: } 114: 115: return asyncResult; 116: } 117: 118: protected void Complete(bool completedSynchronously) 119: { 120: if (isCompleted) 121: { 122: throw new InvalidOperationException("This async result is already completed."); 123: } 124: 125: this.completedSynchronously = completedSynchronously; 126: 127: if (completedSynchronously) 128: { 129: this.isCompleted = true; 130: } 131: else 132: { 133: lock (ThisLock) 134: { 135: this.isCompleted = true; 136: if (this.manualResetEvent != null) 137: { 138: this.manualResetEvent.Set(); 139: } 140: } 141: } 142: 143: if (callback != null) 144: { 145: callback(this); 146: } 147: } 148: 149: protected void Complete(bool completedSynchronously, Exception exception) 150: { 151: this.exception = exception; 152: Complete(completedSynchronously); 153: } 154: } 155: } 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Text; 5: using System.ServiceModel.Discovery; 6: using Phare.Service; 7: 8: namespace Phare.Service 9: { 10: internal sealed class OnOnlineAnnouncementAsyncResult : AsyncResult 11: { 12: public OnOnlineAnnouncementAsyncResult(AsyncCallback callback, object state) 13: : base(callback, state) 14: { 15: this.Complete(true); 16: } 17: 18: public static void End(IAsyncResult result) 19: { 20: AsyncResult.End<OnOnlineAnnouncementAsyncResult>(result); 21: } 22: 23: } 24: 25: sealed class OnOfflineAnnouncementAsyncResult : AsyncResult 26: { 27: public OnOfflineAnnouncementAsyncResult(AsyncCallback callback, object state) 28: : base(callback, state) 29: { 30: this.Complete(true); 31: } 32: 33: public static void End(IAsyncResult result) 34: { 35: AsyncResult.End<OnOfflineAnnouncementAsyncResult>(result); 36: } 37: } 38: 39: sealed class OnFindAsyncResult : AsyncResult 40: { 41: public OnFindAsyncResult(AsyncCallback callback, object state) 42: : base(callback, state) 43: { 44: this.Complete(true); 45: } 46: 47: public static void End(IAsyncResult result) 48: { 49: AsyncResult.End<OnFindAsyncResult>(result); 50: } 51: } 52: 53: sealed class OnResolveAsyncResult : AsyncResult 54: { 55: EndpointDiscoveryMetadata matchingEndpoint; 56: 57: public OnResolveAsyncResult(EndpointDiscoveryMetadata matchingEndpoint, AsyncCallback callback, object state) 58: : base(callback, state) 59: { 60: this.matchingEndpoint = matchingEndpoint; 61: this.Complete(true); 62: } 63: 64: public static EndpointDiscoveryMetadata End(IAsyncResult result) 65: { 66: OnResolveAsyncResult thisPtr = AsyncResult.End<OnResolveAsyncResult>(result); 67: return thisPtr.matchingEndpoint; 68: } 69: } 70: } Now we have finished the discovery service. The next step is to host it. The discovery service is a standard WCF service. So we can use ServiceHost on a console application, windows service, or in IIS as usual. The following code is how to host the discovery service we had just created in a console application. 1: static void Main(string[] args) 2: { 3: using (var host = new ServiceHost(new ManagedProxyDiscoveryService())) 4: { 5: host.Opened += (sender, e) => 6: { 7: host.Description.Endpoints.All((ep) => 8: { 9: Console.WriteLine(ep.ListenUri); 10: return true; 11: }); 12: }; 13: 14: try 15: { 16: // retrieve the announcement, probe endpoint and binding from configuration 17: var announcementEndpointAddress = new EndpointAddress(ConfigurationManager.AppSettings["announcementEndpointAddress"]); 18: var probeEndpointAddress = new EndpointAddress(ConfigurationManager.AppSettings["probeEndpointAddress"]); 19: var binding = Activator.CreateInstance(Type.GetType(ConfigurationManager.AppSettings["bindingType"], true, true)) as Binding; 20: var announcementEndpoint = new AnnouncementEndpoint(binding, announcementEndpointAddress); 21: var probeEndpoint = new DiscoveryEndpoint(binding, probeEndpointAddress); 22: probeEndpoint.IsSystemEndpoint = false; 23: // append the service endpoint for announcement and probe 24: host.AddServiceEndpoint(announcementEndpoint); 25: host.AddServiceEndpoint(probeEndpoint); 26: 27: host.Open(); 28: 29: Console.WriteLine("Press any key to exit."); 30: Console.ReadKey(); 31: } 32: catch (Exception ex) 33: { 34: Console.WriteLine(ex.ToString()); 35: } 36: } 37: 38: Console.WriteLine("Done."); 39: Console.ReadKey(); 40: } What we need to notice is that, the discovery service needs two endpoints for announcement and probe. In this example I just retrieve them from the configuration file. I also specified the binding of these two endpoints in configuration file as well. 1: <?xml version="1.0"?> 2: <configuration> 3: <startup> 4: <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/> 5: </startup> 6: <appSettings> 7: <add key="announcementEndpointAddress" value="net.tcp://localhost:10010/announcement"/> 8: <add key="probeEndpointAddress" value="net.tcp://localhost:10011/probe"/> 9: <add key="bindingType" value="System.ServiceModel.NetTcpBinding, System.ServiceModel, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/> 10: </appSettings> 11: </configuration> And this is the console screen when I ran my discovery service. As you can see there are two endpoints listening for announcement message and probe message. Discoverable Service and Client Next, let’s create a WCF service that is discoverable, which means it can be found by the discovery service. To do so, we need to let the service send the online announcement message to the discovery service, as well as offline message before it shutdown. Just create a simple service which can make the incoming string to upper. The service contract and implementation would be like this. 1: [ServiceContract] 2: public interface IStringService 3: { 4: [OperationContract] 5: string ToUpper(string content); 6: } 1: public class StringService : IStringService 2: { 3: public string ToUpper(string content) 4: { 5: return content.ToUpper(); 6: } 7: } Then host this service in the console application. In order to make the discovery service easy to be tested the service address will be changed each time it’s started. 1: static void Main(string[] args) 2: { 3: var baseAddress = new Uri(string.Format("net.tcp://localhost:11001/stringservice/{0}/", Guid.NewGuid().ToString())); 4: 5: using (var host = new ServiceHost(typeof(StringService), baseAddress)) 6: { 7: host.Opened += (sender, e) => 8: { 9: Console.WriteLine("Service opened at {0}", host.Description.Endpoints.First().ListenUri); 10: }; 11: 12: host.AddServiceEndpoint(typeof(IStringService), new NetTcpBinding(), string.Empty); 13: 14: host.Open(); 15: 16: Console.WriteLine("Press any key to exit."); 17: Console.ReadKey(); 18: } 19: } Currently this service is NOT discoverable. We need to add a special service behavior so that it could send the online and offline message to the discovery service announcement endpoint when the host is opened and closed. WCF 4.0 introduced a service behavior named ServiceDiscoveryBehavior. When we specified the announcement endpoint address and appended it to the service behaviors this service will be discoverable. 1: var announcementAddress = new EndpointAddress(ConfigurationManager.AppSettings["announcementEndpointAddress"]); 2: var announcementBinding = Activator.CreateInstance(Type.GetType(ConfigurationManager.AppSettings["bindingType"], true, true)) as Binding; 3: var announcementEndpoint = new AnnouncementEndpoint(announcementBinding, announcementAddress); 4: var discoveryBehavior = new ServiceDiscoveryBehavior(); 5: discoveryBehavior.AnnouncementEndpoints.Add(announcementEndpoint); 6: host.Description.Behaviors.Add(discoveryBehavior); The ServiceDiscoveryBehavior utilizes the service extension and channel dispatcher to implement the online and offline announcement logic. In short, it injected the channel open and close procedure and send the online and offline message to the announcement endpoint. On client side, when we have the discovery service, a client can invoke a service without knowing its endpoint. WCF discovery assembly provides a class named DiscoveryClient, which can be used to find the proper service endpoint by passing the criteria. In the code below I initialized the DiscoveryClient, specified the discovery service probe endpoint address. Then I created the find criteria by specifying the service contract I wanted to use and invoke the Find method. This will send the probe message to the discovery service and it will find the endpoints back to me. The discovery service will return all endpoints that matches the find criteria, which means in the result of the find method there might be more than one endpoints. In this example I just returned the first matched one back. In the next post I will show how to extend our discovery service to make it work like a service load balancer. 1: static EndpointAddress FindServiceEndpoint() 2: { 3: var probeEndpointAddress = new EndpointAddress(ConfigurationManager.AppSettings["probeEndpointAddress"]); 4: var probeBinding = Activator.CreateInstance(Type.GetType(ConfigurationManager.AppSettings["bindingType"], true, true)) as Binding; 5: var discoveryEndpoint = new DiscoveryEndpoint(probeBinding, probeEndpointAddress); 6: 7: EndpointAddress address = null; 8: FindResponse result = null; 9: using (var discoveryClient = new DiscoveryClient(discoveryEndpoint)) 10: { 11: result = discoveryClient.Find(new FindCriteria(typeof(IStringService))); 12: } 13: 14: if (result != null && result.Endpoints.Any()) 15: { 16: var endpointMetadata = result.Endpoints.First(); 17: address = endpointMetadata.Address; 18: } 19: return address; 20: } Once we probed the discovery service we will receive the endpoint. So in the client code we can created the channel factory from the endpoint and binding, and invoke to the service. When creating the client side channel factory we need to make sure that the client side binding should be the same as the service side. WCF discovery service can be used to find the endpoint for a service contract, but the binding is NOT included. This is because the binding was not in the WS-Discovery specification. In the next post I will demonstrate how to add the binding information into the discovery service. At that moment the client don’t need to create the binding by itself. Instead it will use the binding received from the discovery service. 1: static void Main(string[] args) 2: { 3: Console.WriteLine("Say something..."); 4: var content = Console.ReadLine(); 5: while (!string.IsNullOrWhiteSpace(content)) 6: { 7: Console.WriteLine("Finding the service endpoint..."); 8: var address = FindServiceEndpoint(); 9: if (address == null) 10: { 11: Console.WriteLine("There is no endpoint matches the criteria."); 12: } 13: else 14: { 15: Console.WriteLine("Found the endpoint {0}", address.Uri); 16: 17: var factory = new ChannelFactory<IStringService>(new NetTcpBinding(), address); 18: factory.Opened += (sender, e) => 19: { 20: Console.WriteLine("Connecting to {0}.", factory.Endpoint.ListenUri); 21: }; 22: var proxy = factory.CreateChannel(); 23: using (proxy as IDisposable) 24: { 25: Console.WriteLine("ToUpper: {0} => {1}", content, proxy.ToUpper(content)); 26: } 27: } 28: 29: Console.WriteLine("Say something..."); 30: content = Console.ReadLine(); 31: } 32: } Similarly, the discovery service probe endpoint and binding were defined in the configuration file. 1: <?xml version="1.0"?> 2: <configuration> 3: <startup> 4: <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/> 5: </startup> 6: <appSettings> 7: <add key="announcementEndpointAddress" value="net.tcp://localhost:10010/announcement"/> 8: <add key="probeEndpointAddress" value="net.tcp://localhost:10011/probe"/> 9: <add key="bindingType" value="System.ServiceModel.NetTcpBinding, System.ServiceModel, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/> 10: </appSettings> 11: </configuration> OK, now let’s have a test. Firstly start the discovery service, and then start our discoverable service. When it started it will announced to the discovery service and registered its endpoint into the repository, which is the local dictionary. And then start the client and type something. As you can see the client asked the discovery service for the endpoint and then establish the connection to the discoverable service. And more interesting, do NOT close the client console but terminate the discoverable service but press the enter key. This will make the service send the offline message to the discovery service. Then start the discoverable service again. Since we made it use a different address each time it started, currently it should be hosted on another address. If we enter something in the client we could see that it asked the discovery service and retrieve the new endpoint, and connect the the service. Summary In this post I discussed the benefit of using the discovery service and the procedures of service announcement and probe. I also demonstrated how to leverage the WCF Discovery feature in WCF 4.0 to build a simple managed discovery service. For test purpose, in this example I used the in memory dictionary as the discovery endpoint metadata repository. And when finding I also just return the first matched endpoint back. I also hard coded the bindings between the discoverable service and the client. In next post I will show you how to solve the problem mentioned above, as well as some additional feature for production usage. You can download the code here. Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

Read the article

SSH X11 not working

- by azat

I have a home and work computer, the home computer has a static IP address. If I ssh from my work computer to my home computer, the ssh connection works but X11 applications are not displayed. In my /etc/ssh/sshd_config at home: X11Forwarding yes X11DisplayOffset 10 X11UseLocalhost yes At work I have tried the following commands: xhost + home HOME_IP ssh -X home ssh -X HOME_IP ssh -Y home ssh -Y HOME_IP My /etc/ssh/ssh_config at work: Host * ForwardX11 yes ForwardX11Trusted yes My ~/.ssh/config at work: Host home HostName HOME_IP User azat PreferredAuthentications password ForwardX11 yes My ~/.Xauthority at work: -rw------- 1 azat azat 269 Jun 7 11:25 .Xauthority My ~/.Xauthority at home: -rw------- 1 azat azat 246 Jun 7 19:03 .Xauthority But it doesn't work After I make an ssh connection to home: $ echo $DISPLAY localhost:10.0 $ kate X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. X11 connection rejected because of wrong authentication. kate: cannot connect to X server localhost:10.0 I use iptables at home, but I've allowed port 22. According to what I've read that's all I need. UPD. With -vvv ... debug2: callback start debug2: x11_get_proto: /usr/bin/xauth list :0 2/dev/null debug1: Requesting X11 forwarding with authentication spoofing. debug2: channel 1: request x11-req confirm 1 debug2: client_session2_setup: id 1 debug2: fd 3 setting TCP_NODELAY debug2: channel 1: request pty-req confirm 1 ... When try to launch kate: debug1: client_input_channel_open: ctype x11 rchan 2 win 65536 max 16384 debug1: client_request_x11: request from 127.0.0.1 55486 debug2: fd 8 setting O_NONBLOCK debug3: fd 8 is O_NONBLOCK debug1: channel 2: new [x11] debug1: confirm x11 debug2: X11 connection uses different authentication protocol. X11 connection rejected because of wrong authentication. debug2: X11 rejected 2 i0/o0 debug2: channel 2: read failed debug2: channel 2: close_read debug2: channel 2: input open - drain debug2: channel 2: ibuf empty debug2: channel 2: send eof debug2: channel 2: input drain - closed debug2: channel 2: write failed debug2: channel 2: close_write debug2: channel 2: output open - closed debug2: X11 closed 2 i3/o3 debug2: channel 2: send close debug2: channel 2: rcvd close debug2: channel 2: is dead debug2: channel 2: garbage collecting debug1: channel 2: free: x11, nchannels 3 debug3: channel 2: status: The following connections are open: #1 client-session (t4 r0 i0/0 o0/0 fd 5/6 cc -1) #2 x11 (t7 r2 i3/0 o3/0 fd 8/8 cc -1) # The same as above repeate about 7 times kate: cannot connect to X server localhost:10.0 UPD2 Please provide your Linux distribution & version number. Are you using a default GNOME or KDE environment for X or something else you customized yourself? azat:~$ kded4 -version Qt: 4.7.4 KDE Development Platform: 4.6.5 (4.6.5) KDE Daemon: $Id$ Are you invoking ssh directly on a command line from a terminal window? What terminal are you using? xterm, gnome-terminal, or? How did you start the terminal running in the X environment? From a menu? Hotkey? or ? From terminal emulator `yakuake` Manualy press `Ctrl + N` and write commands Can you run xeyes from the same terminal window where the ssh -X fails? `xeyes` - is not installed But `kate` or another kde app is running Are you invoking the ssh command as the same user that you're logged into the X session as? From the same user UPD3 I also download ssh sources, and using debug2() write why it's report that version is different It see some cookies, and one of them is empty, another is MIT-MAGIC-COOKIE-1

Read the article

GMail suspects confirmation email in stealing personal information

- by Dennis Gorelik

When user registers on my web site, web site sends user email confirmation link. Subject: Please confirm your email address Body:Please open this link in your browser to confirm your email address: http://www.postjobfree.com/a/c301718062444f96ba0e358ea833c9b3 This link will expire on: 6/9/2012 8:04:07 PM EST. If my web site sends that email to GMaill (either @gmail.com or another domain that's handled by Google Apps) and that user never emailed to email -- then GMail not only puts the email to spam folder, but also adds prominent red warning:Be careful with this message. Similar messages were used to steal people's personal information. Unless you trust the sender, don't click links or reply with personal information. Learn more That warning really scares many of my users, so they are afraid to open that link and confirm their email. What can I do about it? Ideally I would like that message end up in user's inbox, not spam folder. But at least how do I prevent that scary message? IP address of my mailing server is not blacklisted: http://www.mxtoolbox.com/SuperTool.aspx?action=blacklist%3a208.43.198.72 I use SPF and DKIM signature. Below is the email that ended up in spam folder with that scary red message. Delivered-To: [email protected] Received: by 10.112.84.98 with SMTP id x2csp36568lby; Fri, 8 Jun 2012 17:04:15 -0700 (PDT) Received: by 10.60.25.6 with SMTP id y6mr9110318oef.42.1339200255375; Fri, 08 Jun 2012 17:04:15 -0700 (PDT) Return-Path: Received: from smtp.postjobfree.com (smtp.postjobfree.com. [208.43.198.72]) by mx.google.com with ESMTP id v8si6058193oev.44.2012.06.08.17.04.14; Fri, 08 Jun 2012 17:04:15 -0700 (PDT) Received-SPF: pass (google.com: domain of [email protected] designates 208.43.198.72 as permitted sender) client-ip=208.43.198.72; Authentication-Results: mx.google.com; spf=pass (google.com: domain of [email protected] designates 208.43.198.72 as permitted sender) [email protected]; dkim=pass [email protected] DomainKey-Signature: a=rsa-sha1; c=nofws; q=dns; d=postjobfree.com; s=postjobfree.com; h= received:message-id:mime-version:from:to:date:subject:content-type; b=TCip/3hP1WWViWB1cdAzMFPjyi/aUKXQbuSTVpEO7qr8x3WdMFhJCqZciA69S0HB4 Koatk2cQQ3fOilr4ledCgZYemLSJgwa/ZRhObnqgPHAglkBy8/RAwkrwaE0GjLKup 0XI6G2wPlh+ReR+inkMwhCPHFInmvrh4evlBx/VlA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=postjobfree.com; s=postjobfree.com; h=content-type:subject:date:to:from:mime-version:message-id; bh=N59EIgRECIlAnd41LY4HY/OFI+v1p7t5M9yP+3FsKXY=; b=J3/BdZmpjzP4I6GA4ntmi4REu5PpOcmyzEL+6i7y7LaTR8tuc2h7fdW4HaMPlB7za Lj4NJPed61ErumO66eG4urd1UfyaRDtszWeuIbcIUqzwYpnMZ8ytaj8DPcWPE3JYj oKhcYyiVbgiFjLujib3/2k2PqDIrNutRH9Ln7puz4= Received: from sv3035 (sv3035 [208.43.198.72]) by smtp.postjobfree.com with SMTP; Fri, 8 Jun 2012 20:04:07 -0400 Message-ID: MIME-Version: 1.0 From: "PostJobFree Notification" To: [email protected] Date: 8 Jun 2012 20:04:07 -0400 Subject: Please confirm your email address Content-Type: multipart/alternative; boundary=--boundary_107_ffa6a9ea-01dc-40f5-a50c-4c3b3d113f08 ----boundary_107_ffa6a9ea-01dc-40f5-a50c-4c3b3d113f08 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Please open this link in your browser to confirm your email addre= ss: =0D=0Ahttp://www.postjobfree.com/a/c301718062444f96ba0e358ea8= 33c9b3 =0D=0AThis link will expire on: 6/9/2012 8:04:07 PM EST. =0D=0A ----boundary_107_ffa6a9ea-01dc-40f5-a50c-4c3b3d113f08 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: base64 PGh0bWw+PGhlYWQ+PG1ldGEgaHR0cC1lcXVpdj1Db250ZW50LVR5cGUgY29udGVu dD0idGV4dC9odG1sOyBjaGFyc2V0PXV0Zi04Ij48L2hlYWQ+DQo8Ym9keT48ZGl2 Pg0KUGxlYXNlIG9wZW4gdGhpcyBsaW5rIGluIHlvdXIgYnJvd3NlciB0byBjb25m aXJtIHlvdXIgZW1haWwgYWRkcmVzczo8YnIgLz48YSBocmVmPSJodHRwOi8vd3d3 LnBvc3Rqb2JmcmVlLmNvbS9hL2MzMDE3MTgwNjI0NDRmOTZiYTBlMzU4ZWE4MzNj OWIzIj5odHRwOi8vd3d3LnBvc3Rqb2JmcmVlLmNvbS9hL2MzMDE3MTgwNjI0NDRm OTZiYTBlMzU4ZWE4MzNjOWIzPC9hPjxiciAvPlRoaXMgbGluayB3aWxsIGV4cGly ZSBvbjogNi85LzIwMTIgODowNDowNyBQTSBFU1QuPGJyIC8+DQo8L2Rpdj48L2Jv ZHk+PC9odG1sPg== ----boundary_107_ffa6a9ea-01dc-40f5-a50c-4c3b3d113f08--

Read the article

Monit won't run

- by Yaniro

I have two identical EC2 instances (the second is a replica of the first), running Gentoo. The first instance has monit running which monitors a single process and some system resources and functions great. In the second instance, monit runs but quits right away. The configuration is similar on both instances so are the versions of monit. monit.log shows: [GMT Oct 3 08:36:41] info : monit daemon with PID 5 awakened Final lines on strace monit show: write(2, "monit daemon with PID 5 awakened"..., 33monit daemon with PID 5 awakened ) = 33 time(NULL) = 1349252827 open("/etc/localtime", O_RDONLY) = 4 fstat64(4, {st_mode=S_IFREG|0644, st_size=118, ...}) = 0 fstat64(4, {st_mode=S_IFREG|0644, st_size=118, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb773a000 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1\0\0\0\1\0\0\0\0"..., 4096) = 118 _llseek(4, -6, [112], SEEK_CUR) = 0 read(4, "\nGMT0\n", 4096) = 6 close(4) = 0 munmap(0xb773a000, 4096) = 0 write(3, "[GMT Oct 3 08:27:07] info :"..., 33) = 33 write(3, "monit daemon with PID 5 awakened"..., 33) = 33 waitpid(-1, NULL, WNOHANG) = -1 ECHILD (No child processes) close(3) = 0 exit_group(0) = ? No core dumps (ulimit -c shows unlimited) monit -v shows: monit: Debug: Adding host allow 'localhost' monit: Debug: Skipping redundant host 'localhost' monit: Debug: Skipping redundant host 'localhost' monit: Debug: Adding credentials for user 'xxxx'. Runtime constants: Control file = /etc/monitrc Log file = /var/log/monit/monit.log Pid file = /var/run/monit.pid Id file = /var/run/monit.pid Debug = True Log = True Use syslog = False Is Daemon = True Use process engine = True Poll time = 30 seconds with start delay 0 seconds Expect buffer = 256 bytes Event queue = base directory /var/monit with 100 slots Mail server(s) = xx.xxx.xx.xxx with timeout 30 seconds Mail from = (not defined) Mail subject = (not defined) Mail message = (not defined) Start monit httpd = True httpd bind address = Any/All httpd portnumber = 2812 httpd signature = True Use ssl encryption = False httpd auth. style = Basic Authentication and Host/Net allow list Alert mail to = [email protected] Alert on = All events The service list contains the following entries: System Name = xxxx Monitoring mode = active CPU wait limit = if greater than 20.0% 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert CPU system limit = if greater than 30.0% 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert CPU user limit = if greater than 70.0% 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert Swap usage limit = if greater than 25.0% 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert Memory usage limit = if greater than 75.0% 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert Load avg. (5min) = if greater than 2.0 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert Load avg. (1min) = if greater than 4.0 1 times within 1 cycle(s) then alert else if succeeded 1 times within 1 cycle(s) then alert Process Name = xxxx Group = server Pid file = /var/run/xxxx.pid Monitoring mode = active Start program = '/etc/init.d/xxxx restart' timeout 20 second(s) Stop program = '/etc/init.d/xxxx stop' timeout 30 second(s) Existence = if does not exist 1 times within 1 cycle(s) then restart else if succeeded 1 times within 1 cycle(s) then alert Pid = if changed 1 times within 1 cycle(s) then alert Ppid = if changed 1 times within 1 cycle(s) then alert Timeout = If restarted 3 times within 5 cycle(s) then unmonitor Alert mail to = [email protected] Alert on = All events Alert mail to = [email protected] Alert on = All events ------------------------------------------------------------------------------- monit daemon with PID 5 awakened Ran emerge --sync before emerge -va monit which installed monit v5.3.2. When that didn't work i've downloaded v5.5 from their website and compiled from source which did not work either.

Read the article

How to configure emacs by using this file?

- by Andy Leman

From http://public.halogen-dg.com/browser/alex-emacs-settings/.emacs?rev=1346 I got: (setq load-path (cons "/home/alex/.emacs.d/" load-path)) (setq load-path (cons "/home/alex/.emacs.d/configs/" load-path)) (defconst emacs-config-dir "~/.emacs.d/configs/" "") (defun load-cfg-files (filelist) (dolist (file filelist) (load (expand-file-name (concat emacs-config-dir file))) (message "Loaded config file:%s" file) )) (load-cfg-files '("cfg_initsplit" "cfg_variables_and_faces" "cfg_keybindings" "cfg_site_gentoo" "cfg_conf-mode" "cfg_mail-mode" "cfg_region_hooks" "cfg_apache-mode" "cfg_crontab-mode" "cfg_gnuserv" "cfg_subversion" "cfg_css-mode" "cfg_php-mode" "cfg_tramp" "cfg_killbuffer" "cfg_color-theme" "cfg_uniquify" "cfg_tabbar" "cfg_python" "cfg_ack" "cfg_scpaste" "cfg_ido-mode" "cfg_javascript" "cfg_ange_ftp" "cfg_font-lock" "cfg_default_face" "cfg_ecb" "cfg_browser" "cfg_orgmode" ; "cfg_gnus" ; "cfg_cyrillic" )) ; enable disabled advanced features (put 'downcase-region 'disabled nil) (put 'scroll-left 'disabled nil) (put 'upcase-region 'disabled nil) ; narrow cursor ;(setq-default cursor-type 'hbar) (cua-mode) ; highlight current line (global-hl-line-mode 1) ; AV: non-aggressive scrolling (setq scroll-conservatively 100) (setq scroll-preserve-screen-position 't) (setq scroll-margin 0) (custom-set-variables ;; custom-set-variables was added by Custom. ;; If you edit it by hand, you could mess it up, so be careful. ;; Your init file should contain only one such instance. ;; If there is more than one, they won't work right. '(ange-ftp-passive-host-alist (quote (("redbus2.chalkface.com" . "on") ("zope.halogen-dg.com" . "on") ("85.119.217.50" . "on")))) '(blink-cursor-mode nil) '(browse-url-browser-function (quote browse-url-firefox)) '(browse-url-new-window-flag t) '(buffers-menu-max-size 30) '(buffers-menu-show-directories t) '(buffers-menu-show-status nil) '(case-fold-search t) '(column-number-mode t) '(cua-enable-cua-keys nil) '(user-mail-address "[email protected]") '(cua-mode t nil (cua-base)) '(current-language-environment "UTF-8") '(file-name-shadow-mode t) '(fill-column 79) '(grep-command "grep --color=never -nHr -e * | grep -v .svn --color=never") '(grep-use-null-device nil) '(inhibit-startup-screen t) '(initial-frame-alist (quote ((width . 80) (height . 40)))) '(initsplit-customizations-alist (quote (("tabbar" "configs/cfg_tabbar.el" t) ("ecb" "configs/cfg_ecb.el" t) ("ange\\-ftp" "configs/cfg_ange_ftp.el" t) ("planner" "configs/cfg_planner.el" t) ("dired" "configs/cfg_dired.el" t) ("font\\-lock" "configs/cfg_font-lock.el" t) ("speedbar" "configs/cfg_ecb.el" t) ("muse" "configs/cfg_muse.el" t) ("tramp" "configs/cfg_tramp.el" t) ("uniquify" "configs/cfg_uniquify.el" t) ("default" "configs/cfg_font-lock.el" t) ("ido" "configs/cfg_ido-mode.el" t) ("org" "configs/cfg_orgmode.el" t) ("gnus" "configs/cfg_gnus.el" t) ("nnmail" "configs/cfg_gnus.el" t)))) '(ispell-program-name "aspell") '(jabber-account-list (quote (("[email protected]")))) '(jabber-nickname "AVK") '(jabber-password nil) '(jabber-server "halogen-dg.com") '(jabber-username "alex") '(remember-data-file "~/Plans/remember.org") '(safe-local-variable-values (quote ((dtml-top-element . "body")))) '(save-place t nil (saveplace)) '(scroll-bar-mode (quote right)) '(semantic-idle-scheduler-idle-time 432000) '(show-paren-mode t) '(svn-status-hide-unmodified t) '(tool-bar-mode nil nil (tool-bar)) '(transient-mark-mode t) '(truncate-lines f) '(woman-use-own-frame nil)) ; ?? ????? ??????? y ??? n? (fset 'yes-or-no-p 'y-or-n-p) (custom-set-faces ;; custom-set-faces was added by Custom. ;; If you edit it by hand, you could mess it up, so be careful. ;; Your init file should contain only one such instance. ;; If there is more than one, they won't work right. '(compilation-error ((t (:foreground "tomato" :weight bold)))) '(cursor ((t (:background "red1")))) '(custom-variable-tag ((((class color) (background dark)) (:inherit variable-pitch :foreground "DarkOrange" :weight bold)))) '(hl-line ((t (:background "grey24")))) '(isearch ((t (:background "orange" :foreground "black")))) '(message-cited-text ((((class color) (background dark)) (:foreground "SandyBrown")))) '(message-header-name ((((class color) (background dark)) (:foreground "DarkGrey")))) '(message-header-other ((((class color) (background dark)) (:foreground "LightPink2")))) '(message-header-subject ((((class color) (background dark)) (:foreground "yellow2")))) '(message-separator ((((class color) (background dark)) (:foreground "thistle")))) '(region ((t (:background "brown")))) '(tooltip ((((class color)) (:inherit variable-pitch :background "IndianRed1" :foreground "black"))))) The above is a python emacs configure file. Where should I put it to use it? And, are there any other changes I need to make?

Read the article

Apache doesn't run multiple requests

- by Reinderien

I'm currently running this simple Python CGI script to test rudimentary IPC: #!/usr/bin/python -u import cgi, errno, fcntl, os, os.path, sys, time print("""Content-Type: text/html; charset=utf-8 <!doctype html> <html lang="en"> <head> <meta charset="utf-8" /> <title>IPC test</title> </head> <body> """) ftempname = '/tmp/ipc-messages' master = not os.path.exists(ftempname) if master: fmode = 'w' else: fmode = 'r' print('Opening file') sys.stdout.flush() ftemp = open(ftempname, fmode) print('File opened') if master: print('Operating as master') sys.stdout.flush() for i in range(10): print('' + str(i) + '') sys.stdout.flush() time.sleep(1) ftemp.close() os.remove(ftempname) else: print('Operating as a slave') ftemp.close() print(""" </body> </html>""") The 'server-push' portion works; that is, for the first request, I do see piecewise updates. However, while the first request is being serviced, subsequent requests are not started, only to be started after the first request has finished. Any ideas on why, and how to fix it? Edit: I see the same non-concurrent behaviour with vanilla PHP, running this: <!doctype html> <html lang="en">  <head> <meta charset="utf-8" /> <title>IPC test</title> </head> <body> <?php function echofl($str) { echo $str . "\n"; ob_flush(); flush(); } define('tempfn', '/tmp/emailsync'); if (file_exists(tempfn)) $perms = 'r+'; else $perms = 'w'; assert($fsync = fopen(tempfn, $perms)); assert(chmod(tempfn, 0600)); if (!flock($fsync, LOCK_EX | LOCK_NB, $wouldblock)) { assert($wouldblock); $master = false; } else $master = true; if ($master) { echofl('Running as master.'); assert(fwrite($fsync, 'content') != false); assert(sleep(5) == 0); assert(flock($fsync, LOCK_UN)); } else { echofl('Running as slave.'); echofl(fgets($fsync)); } assert(fclose($fsync)); echofl('Done.'); ?> </body> </html>

Read the article

Intermittent 404 on select assets, LAMP stack

- by Tom Lagier

We have a LAMP stack WordPress server that is serving most assets correctly. However, one plugin's CSS file and several images are returning soft 404s roughly 20% of the time. I can't find any reference to the 404 in the access logs, but the browser is definitely receiving a 404 response from somewhere (WordPress, I would assume). When I use an alias URL that does not match the site URL but does resolve to the asset path, the resource loads correctly 100% of the time. However, using the site url only resolves for the select, problematic assets 20% of the time. You can test one of the problematic assets here: http://www.mreco.org/wp-content/uploads/2014/05/zero-cost.jpg However the alias link always resolves correctly: http://mr-eco.wordpress.promocampaigns.com/wp-content/uploads/2014/05/zero-cost.jpg Stranger, if I attempt to access outdated content that definitely does not exist on the server, at the live URL it returns the content roughly 50% of the time. Using the alias link, it 404s 100% of the time - the correct behavior. Error log and PHP error log are clean. A sample access log (pulled from grep 'zero-cost.jpg' /var/log/httpd/mr-eco-access_log) from several refreshes of the live direct link (where I am not seeing any 404's): 10.166.202.202 - - [28/May/2014:20:27:41 +0000] "GET /wp-content/uploads/2014/05/zero-cost.jpg HTTP/1.1" 304 - 10.166.202.202 - - [28/May/2014:20:27:42 +0000] "GET /wp-content/uploads/2014/05/zero-cost.jpg HTTP/1.1" 304 - 10.166.202.202 - - [28/May/2014:20:27:43 +0000] "GET /wp-content/uploads/2014/05/zero-cost.jpg HTTP/1.1" 304 - 10.166.202.202 - - [28/May/2014:20:27:43 +0000] "GET /wp-content/uploads/2014/05/zero-cost.jpg HTTP/1.1" 304 - 10.176.201.37 - - [28/May/2014:20:27:56 +0000] "GET /wp-content/uploads/2014/05/zero-cost.jpg HTTP/1.1" 200 57027 Chrome's dev tools list the following network activity before displaying 404 page content: zero-cost.jpg /wp-content/uploads/2014/05 GET 404 Not Found text/html Other 15.9?KB 73.2?KB 953?ms 947?ms My Apache configuration is standard, I've listed the virtual host entry and .htaccess file below. I can provide other parts of Apache config if necessary. Virtual host: <VirtualHost *:80> DocumentRoot /var/www/public_html/mr-eco.wordpress.promocampaigns.com ServerName www.mreco.org ServerAlias mreco.org mr-eco.wordpress.promocampaigns.com ErrorLog logs/mr-eco-error_log CustomLog logs/mr-eco-access_log common <Directory /var/www/public_html/mr-eco.wordpress.promocampaigns.com> AllowOverride All SetOutputFilter DEFLATE </Directory> </VirtualHost> .htaccess: # BEGIN WordPress <IfModule mod_rewrite.c> RewriteEngine On RewriteBase / RewriteRule ^index\.php$ - [L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /index.php [L] </IfModule> # END WordPress I have checked for multiple A records and can confirm that there is a single A record pointing at the domain: ;; ANSWER SECTION: mreco.org. 60 IN A 50.18.58.174 I'm fairly new to systems administration, and at a complete loss as to what could cause this. In the past, inconsistently 404ing assets have been because of out-of-sync instances behind a load balancer. In this case, it is a single instance behind the load balancer. Because of the inconsistency, it feels like a caching issue. We don't make use of Apache caching, and as far as I know WordPress should not be caching either. What I've done so far: Reset WordPress permalinks Disabled WordPress plugins Re-generated WordPress .htaccess file Swapped ServerName and ServerAlias directives Cleared browser cache Confirmed disk location of resources Checked PHP, access, and error logs Confirmed correct DNS setup (can post if necessary) I'm at a total loss. Thanks for helping me out!

Read the article

What would make a noise in a PC on graphics operations on a passively-cooled system?

- by T.J. Crowder

I have this system based on the Intel D510MO motherboard, which is basically an Atom D510 (dual-core HT Atom w/built-in GPU), an Intel NM10 chipset, and a Realtek Gigabit LAN controller. It's entirely passively cooled. I noticed almost immediately that there was a kind of very, very soft noise that corresponded with graphics operations, sort of the noise you'd get if you had a sheet of flat paper and slid something really light across it — but more electronic than that. I wrote it off as observation error and/or disk activity triggered by the graphics operation (although the latter seemed like a lot of unnecessary disk activity). It isn't. I got curious enough that I finally did a few controlled experiments, and here's what I've determined: It isn't the HDD. For one thing, the sounds the HDD makes (when seeking, when reading or writing, when just sitting there spinning) is different. For another, I used sudo hdparm -y /dev/sda (I'm using Ubuntu 10.04 LTS) to temporarily put the disk on standby while making sure that non-disk graphics op was happening in a loop. The disk spun down, but the other sound continued, corresponding perfectly with the timing of the graphics op. (Then the disk spun up again, but it takes long enough that I could rule out the HDD.) It isn't the monitor; I ensured the two were well physically-separated and the sound was definitely coming from the main box. It isn't something else in the room; the sound is coming from the box. It isn't cross-talk to an audio circuit coming out the speakers. (It doesn't have any speakers.) It isn't my mouse (e.g., when I'm trying to make graphics ops happen); the sound happens if I set up a recurring operation and don't use the mouse at all, or if I lift the mouse off the table slightly (but enough that the laser still registers movement). It isn't the voices in my head; they never whisper like that. Other observations: It doesn't seem to matter what the graphics operation is; anything that changes what's on the screen seems to do it. I get the sound when moving the mouse over the Chromium tab bar (which makes the tab backgrounds change); I get it when a web page has a counter on it that changes the text on the page: I get it when dragging window contents around. The sound is very, very slightly louder if the graphics op is larger, like scrolling a text area when writing a question on superuser.com, than for smaller operations like the tick counter on the web page. But it's very slight. It's fairly loud (and of good duration) when the op involves color changes to substantial surface areas. For instance, when asking a question here on superuser and you move the cursor between the question box and the tag box, and the help to the right fades out, changes, and fades back in. (Yet another example related to the web browser, so let me say: I hear it when operations completely unrelated to the web browser as well.) It doesn't sound like arcing or anything like that (I'd've shut off the machine Right Quick Like if it did). Moving windows does it. Scrolling windows (by and large) doesn't. I have the feeling I've heard this sort of thing before, when all system fans were on low and such, with other systems — but (again) written it off as observational error. For all the world it's like I'm hearing the CPU working (as opposed to the GPU; note the window scroll thing above) or data being transferred somewhere, but that just seems...unlikely. So what am I hearing? This may seem like a very localized question, but perhaps other silent PC enthusiasts may be interested as well...

Read the article

Local DNS server (bind) and the router DHCP

- by Luca

I just set up an internal http server for internal use (I set up Redmine), in a small network (30 or so PCs). I set up the http server on a virtual box ubuntu, that runs also the DNS server (bind). In the DNS lookup I added the Redmine server name (redmine.engserver <- 192.168.1.14) and as forwarders the outside ISP DNS IP adresses. I am using a small wi-fi router (ASUS RT-N66U) as DHCP (and as gateway). In the DHCP config page I set up as DNS the ubuntu server IP (it is fixed 192.168.1.14). Now when I connect a new PC to the network, the DHCP router issues its new IP and as DNS servers it issues: primary: 192.168.1.14 (ubuntu machine) and seconary 192.168.1.1 (the router itself). ipconfig /all Default Gateway . . . . . . . . . : 192.168.1.1 DHCP Server . . . . . . . . . . . : 192.168.1.1 DHCPv6 IAID . . . . . . . . . . . : 248539109 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-15-AA-3F-D0-67-E5-49-A7-EF DNS Servers . . . . . . . . . . . : 192.168.1.14 192.168.1.1 NetBIOS over Tcpip. . . . . . . . : Enabled Before changing the DHCP setting on the router, I would always get only one DNS server: 192.168.1.1 (which uses probably DNS forwarding to external public DNS services). The problem is this: If in my browser I type www.google.com, it works all the time. If in the browser I type http://redmine.engserver/ it works most of the time, but sometimes it ends up with a yahoo page search or something else. In the DNS cache it shows as (Server not found). ipconfig /displaydns I looked with wireshark and it seems like sometimes the client PC interrogates the secondary DNS (192.168.1.1) instead of the first 192.168.1.14. Obviously this one is a public domain and it does not have the redmine.engserver entry. What is wrong in this configuration? Is it even legitimate to have 2 DNS (one internal and one forwarded by the router) which are inconsistent? Is there another way to have a local name service in a small office network? Why is the router DHCP issuing itself as DNS?

Read the article

How to troubleshoot a PHP script that causes a Segmenation Fault?

- by johnlai2004

I posted this on stackoverflow.com as well because I'm not sure if this is a programming problem or a server problem. I'm using ubuntu 9.10, apache2, mysql5 and php5. I've noticed an unusual problem with some of my php programs. Sometimes when visiting a page like profile.edit.php, the browser throws a dialogue box asking to download profile.edit.php page. When I download it, there's nothing in the file. profile.edit.php is supposed to be a web form that edits user information. I've noticed this on some of my other php pages as well. I look in my apache error logs, and I see a segmentation fault message: [Mon Mar 08 15:40:10 2010] [notice] child pid 480 exit signal Segmentation fault (11) And also, the issue may or may not appear depending on which server I deploy my application too. Additonal Details This doesn't happen all the time though. It only happens sometimes. For example, profile.edit.php will load properly. But as soon as I hit the save button (form action="profile.edit.php?save=true"), then the page asks me to download profile.edit.php. Could it be that sometimes my php scripts consume too much resources? Sample code Upon save action, my profile.edit.php includes a data_access_object.php file. I traced the code in data_access_object.php to this line here if($params[$this->primaryKey]) { $q = "UPDATE $this->tableName SET ".implode(', ', $fields)." WHERE ".$this->primaryKey." = ?$this->primaryKey"; $this->bind($this->primaryKey, $params[$this->primaryKey], $this->tblFields[$this->primaryKey]['mysqlitype']); } else { $q = "INSERT $this->tableName SET ".implode(', ', $fields); } // Code executes perfectly up to this point // echo 'print this'; exit; // if i uncomment this line, profile.edit.php will actually show 'print this'. If I leave it commented, the browser will ask me to download profile.edit.php if(!$this->execute($q)){ $this->errorSave = -3; return false;} // When I jumped into the function execute(), every line executed as expected, right up to the return statement. And if it helps, here's the function execute($sql) in data_access_object.php function execute($sql) { // find all list types and explode them // eg. turn ?listId into ?listId0,?listId1,?listId2 $arrListParam = array_bubble_up('arrayName', $this->arrBind); foreach($arrListParam as $listName) if($listName) { $explodeParam = array(); $arrList = $this->arrBind[$listName]['value']; foreach($arrList as $key=>$val) { $newParamName = $listName.$key; $this->bind($newParamName,$val,$this->arrBind[$listName]['type']); $explodeParam[] = '?'.$newParamName; } $sql = str_replace("?$listName", implode(',',$explodeParam), $sql); } // replace all ?varName with ? for syntax compliance $sqlParsed = preg_replace('/\?[\w\d_\.]+/', '?', $sql); $this->stmt->prepare($sqlParsed); // grab all the parameters from the sql to create bind conditions preg_match_all('/\?[\w\d_\.]+/', $sql, $matches); $matches = $matches[0]; // store bind conditions $types = ''; $params = array(); foreach($matches as $paramName) { $types .= $this->arrBind[str_replace('?', '', $paramName)]['type']; $params[] = $this->arrBind[str_replace('?', '', $paramName)]['value']; } $input = array('types'=>$types) + $params; // bind it if(!empty($types)) call_user_func_array(array($this->stmt, 'bind_param'), $input); $stat = $this->stmt->execute(); if($GLOBALS['DEBUG_SQL']) echo 'SQL error after execution: ' . $this->stmt->error.' '; $this->arrBind = array(); return $stat; }

Read the article

IP Micro-outages, telephone micro-outages, and CATV micro-outages

- by Michael Graff

This is a long and complicated question, mostly because it has been going on for 2.5 years without a solution in sight. It also is only one-third computer related, the other two-thirds are cable TV and cable-phone related. Background I have COX Communications for a cable provider, and we get Internet, digital cable TV, and digital phone service through them. The Internet is a SB5101 right now, and has been a DPC2100 and SB5120 in the past. Same results. The phone service is provided through a telephone interface mounted on the outside of the house (not classic VoIP) and the CATV is through a Scientific Atlanta receiver without DVR. I do have a TiVo connected to the CATV box. Symptoms The CATV shows "blocking" -- sometimes very very short duration where a few blocks appear on the screen. Sometimes it lasts long enough that the video "pauses" for 2-5 seconds, and rarely but not unseen the audio also fails. The CATV decoder box shows no correctable (FEC) or uncorrectable errors. That is, all BER counters are zero for the video stream. The Internet shows "micro-outages" where it appears that sent packets are not making it out, but I continue to receive packets from local modems. That is, pings stop coming back, but I continue to see modems broadcast for DHCP, and sometimes they ask more than once. The cable modem shows no errors during this time, but cable modems lie like you would not believe. It is actually possible to unplug the coax from the modem for 20 seconds and it reports NO ERRORS to the provider's tools. The phone service cuts out for 1-3 seconds, infrequently. When this happens, I hear NOTHING (not even comfort noise) and the remote side hears a "click" as if I were getting a call waiting message. However, there is no call incoming, other than the one I'm currently on of course. Things SEEM to happen more frequently when the temperature outside swings from cold to warm, so fall/spring seems worse than summer/winter. All micro-outages occur between once or twice a day (which I could ignore) to 10 times per hour. All SNR, signal levels, noise levels, etc. show very close to optimal when measured. COX's diagnosis This is a continual pain for me. Over the last 2.5 years, they have opened, "fixed" something, and closed the tickets. They close it without confirming that it is indeed better, and when I reopen they cannot do that, but instead they open a new ticket and send yet another low-level tech out to do the same signal tests and report that all is OK. I've finally gotten a line tech who has a clue and is motivated enough to pursue this with me. We have tried things like switching the local nodes over to UPS and generator power, but this does not trigger the noise. We have tried replacing all cabling, the tap outside my house, the modem, the CATV decoder -- all without resolution. Recently they have decided it is both my computer or switch, my TiVo, and my phone that are all broken and causing this issue. My debugging steps I spent the worse day of my TV-watching life yesterday and part of today. I watched live TV without the TiVo. I witnessed blocking, but it did "feel different." and was actually more severe. Some days it is better, some days it is worse, so perhaps this was just a very bad day. Today, I connected the TiVo to my DVD player, and ran two very long movies through it. I saw no blocking at all during nearly 6 hours of video. Suggestions? Does anyone have any suggestions on what to do next? I understand perhaps only the IP side can be addressed here, but it is one of the more limiting debugging options.

Read the article

Alternative Methods of Sharing Folders in Windows?

- by Blaenk

Hey guys. I'm running Windows 7 and as of now I simply share folders as one usually does in Windows. I then have a MacBook with Leopard (Now Snow Leopard) which I use to connect to my computer to mount the shares by going to Finder, then CMD + K and typing smb://BlaenkPC (The name of my PC) into the address box. This consequently connects to my computer and mounts all of the shares. The problem is that sometimes, if for example I close my MacBook (Which makes it go to sleep) or sometimes even without doing that, the connection somehow drops. Sometimes I close the MacBook and upon re-opening it, everything still works; it's random. It still shows the computer as being connected, but it just shows 'loading' indefinitely. If I hit 'eject' with the intention of re-connecting to the computer, it disappears from the sidebar (The Computer Icon) in Finder, but I cannot re-connect. Activity Monitor (or ps aux, whichever) both show hung instances of umount; one for each share that was mounted. I cannot kill these processes with kill or killall (Yes, even with sudo, and sending signal -9). This has happened to me before, and here is another person who has experienced this. My question boils down to this: Is there an alternative method of sharing folders in Windows, that my Mac can read/understand, that is possibly more reliable and preferably just as fast? I usually use the mounted shares to watch television episodes off my computer, or movies, etc. (In other words, I open them in VLC and they automatically stream from my computer). As far as I can tell, this is a problem with the Samba protocol. I have heard of NFS, but I am not sure if I would have to re-format my drives, or what. I don't mind running a service or daemon to allow the sharing of the folders, I just want it to be done and hopefully in a better way than typical Windows shares through Samba. Usually when I encounter this problem, which is often (read: every day), I have no other option but to restart the MacBook. As I stated in the first question I linked to, shutting down and restarting don't work; I have to manually force the shutdown by holding the power button. I have not modified my installation of Mac OS X in any hackish way, so I doubt it's something with the Operating System, but worst come to worst, I might end up reformatting and doing a clean install to see if that fixes anything, as I am at a complete loss as to what may be causing the problem, and no one else seems to have any idea or care, despite there being quite a few people suffering from this problem, as my research has shown. Any pieces of information that can help are extremely appreciated. You don't have to answer every question on here, but maybe even some insight as to why it might not be possible to kill those hung umount instances for example, or why I may not be able to reconnect using samba (Is it something regarding the way the protocol works?). One thing to note is that I have another computer in the home network that doesn't seem to have this problem. However, it is also running Windows 7 (Note though that I am not using the homegroup feature, but the typical windows sharing feature). My only deduction is that the problem is being caused by the way the Mac (Or Samba implementation, whichever) is handling things. Perhaps it is a limitation.

Read the article

How to stop Apache from crashing my entire server?

- by CyberShadow

I maintain a Gentoo server with a few services, including Apache. It's fairly low-end (2GB of RAM and a low-end CPU with 2 cores). My problem is that, despite my best efforts, an over-loaded Apache crashes the entire server. In fact, at this point I'm close to being convinced that Linux is a horrible operating system that isn't worth anyone's time looking for stability under load. Things I tried: Adjusting oom_adj for the root Apache process (and thus all its children). That had close to no effect. When Apache was overloaded it would bring the system to a grind, as the system paged out everything else before it got to kill anything. Turning off swap. Didn't help, it would unload memory paged to binaries of processes and other files on /, thus causing the same effect. Putting it in a memory-limited cgroup (limited to 512 MB of RAM, 1/4th of the total). This "worked", at least in my own stress tests - except the server keeps crashing under load (basically stalling all other processes, inaccessible via SSH, etc.) Running it with idle I/O priority. This wasn't a very good idea in the end, because it just caused the system load to climb indefinitely (into the thousands) with almost no visible effect - until you tried to access an unbuffered part of the disk. This caused the task to freeze. (So much for good I/O scheduling, eh?) Limiting the number of concurrent connections to Apache. Setting the number too low caused web sites to become unresponsive due to most slots being occupied with long requests (file downloads). I tried various Apache MPMs without much success (prefork, event, itk). Switching from prefork/event+php-cgi+suphp to itk+mod_php. This improved performance, but didn't solve the actual problem. Switching I/O schedulers (cfq to deadline). Just to stress this out: I don't care if Apache itself goes down under load, I just want the rest of my system to remain stable. Of course, having Apache recover quickly after a brief period of intensive load would be great to have, but one step at a time. Right now I am mostly dumbfounded by how can humanity, in this day and age, design an operating system where such a seemingly simple task (don't allow one system component to crash the entire system) seems practically impossible - or at least, very hard to do. Please don't suggest things like VMs or "BUY MORE RAM". Some more information gathered with a friend's help: The processes hang when the cgroup oom killer is invoked. Here's the call trace: [<ffffffff8104b94b>] ? prepare_to_wait+0x70/0x7b [<ffffffff810a9c73>] mem_cgroup_handle_oom+0xdf/0x180 [<ffffffff810a9559>] ? memcg_oom_wake_function+0x0/0x6d [<ffffffff810aa041>] __mem_cgroup_try_charge+0x32d/0x478 [<ffffffff810aac67>] mem_cgroup_charge_common+0x48/0x73 [<ffffffff81081c98>] ? __lru_cache_add+0x60/0x62 [<ffffffff810aadc3>] mem_cgroup_newpage_charge+0x3b/0x4a [<ffffffff8108ec38>] handle_mm_fault+0x305/0x8cf [<ffffffff813c6276>] ? schedule+0x6ae/0x6fb [<ffffffff8101f568>] do_page_fault+0x214/0x22b [<ffffffff813c7e1f>] page_fault+0x1f/0x30 At this point, the apache memory cgroup is practically deadlocked, and burning CPU in syscalls (all with the above call trace). This seems like a problem in the cgroup implementation...

Read the article

Apache access.log interpretation

- by Pantelis Sopasakis

In the log file of apache (access.log) I find log entries like the following: 10.20.30.40 - - [18/Mar/2011:02:12:44 +0200] "GET /index.php HTTP/1.1" 404 505 "-" "Opera/9.80 (Windows NT 6.1; U; en) Presto/2.7.62 Version/11.01" Whose meaning is clear: The client with IP 10.20.30.40 applied a GET HTTP method on /index.php (that is to say http://mysite.org/index.php) receiving a status code 404 using Opera as client/browser. What I don't understand is entries like the following: 174.34.231.19 - - [18/Mar/2011:02:24:56 +0200] "GET http://www.siasatema.com HTTP/1.1" 200 469 "-" "Python-urllib/2.4" So here what I see is that someone (client with IP 174.34.231.19) accessed http://www.siasatema.com and got a 200 HTTP status code(?). It doesn't make sense to me... the only interpretation I can think of is that my apache server acts like proxy! Here are some other requests that don't have my site as destination... 187.35.50.61 - - [18/Mar/2011:01:28:20 +0200] "POST http://72.26.198.222:80/log/normal/ HTTP/1.0" 404 491 "-" "Octoshape-sua/1010120" 87.117.203.177 - - [18/Mar/2011:01:29:59 +0200] "CONNECT 64.12.244.203:80 HTTP/1.0" 405 556 "-" "-" 87.117.203.177 - - [18/Mar/2011:01:29:59 +0200] "open 64.12.244.203 80" 400 506 "-" "-" 87.117.203.177 - - [18/Mar/2011:01:30:04 +0200] "telnet 64.12.244.203 80" 400 506 "-" "-" 87.117.203.177 - - [18/Mar/2011:01:30:09 +0200] "64.12.244.203 80" 400 301 "-" "-" I believe that all these are related to some kind of attack or abuse of the server. Could someone explain to may what is going on and how to cope with this situation? Update 1: I disabled mod_proxy to make sure that I don't have an open proxy: # a2dismod proxy Where from I got the message: Module proxy already disabled I made sure that there is no file proxy.conf under $APACHE/mods-enabled. Finally, I set on my browser (Mozzila) my IP as a proxy and tried to access http://google.com. I was not redirected to google.com but instead my web page appeared. The same happened with trying to access http://a.b (!). So my server does not really work as a proxy since it does not forward the requests... But I think it would be better if somehow I could configure it to return a status code 403. Here is my apache configuration file: <VirtualHost *:80> ServerName mysite.org ServerAdmin webmaster@localhost DocumentRoot /var/www/ <Directory /> Options FollowSymLinks AllowOverride None </Directory> <Directory /var/www/> Options Indexes FollowSymLinks MultiViews AllowOverride None Order allow,deny allow from all </Directory> ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/ <Directory "/usr/lib/cgi-bin"> AllowOverride None Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all </Directory> ErrorLog /var/log/apache2/error.log LogLevel warn CustomLog /var/log/apache2/access.log combined Alias /doc/ "/usr/share/doc/" <Directory "/usr/share/doc/"> Options Indexes MultiViews FollowSymLinks AllowOverride None Order deny,allow Deny from all Allow from 127.0.0.0/255.0.0.0 ::1/128 </Directory> </VirtualHost> Update 2: Using a block, I restrict the use of other methods than GET and POST... <Limit POST PUT CONNECT HEAD OPTIONS DELETE PATCH PROPFIND PROPPATCH MKCOL COPY MOVE LOCK UNLOCK> Order deny,allow Deny from all </Limit> <LimitExcept GET> Order deny,allow Deny from all </LimitExcept> Now methods other that GET are forbidden (403). My only question now is whether there is some trick to boot those how try to use my server as a proxy out...

Read the article

All client browsers repeatedly asking for NTLM authentication when running through local proxy server

- by Marko

All client browsers repeatedly asking for NTLM authentication when running through local proxy server. When pointing browsers through the local proxy to the internet, some but not all clients are being repeatedley prompted to authenticate to the proxy server. I have inspected the headers using firefox live headers as well as fiddler, and in all cases the authentication prompts happen when requesting SSL resources. an example of this would be as follows: GET http://gmail.google.com/mail/ HTTP/1.1 Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave- flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms- xpsdocument, application/xaml+xml, */* Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Accept-Encoding: gzip, deflate Proxy-Connection: Keep-Alive Host: gmail.google.com GET http://gmail.google.com/mail/ HTTP/1.1 Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave- flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms- xpsdocument, application/xaml+xml, */* Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Accept-Encoding: gzip, deflate Proxy-Connection: Keep-Alive Host: gmail.google.com Proxy-Authorization: NTLM TlRMTVNTUAABAAAAB7IIogkACQAvAAAABwAHACgAAAAFASgKAAAAD1dJTlhQMUdGTEFHU0hJUDc= GET http://gmail.google.com/mail/ HTTP/1.1 Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave- flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms- xpsdocument, application/xaml+xml, */* Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Accept-Encoding: gzip, deflate Proxy-Connection: Keep-Alive Proxy-Authorization: NTLM TlRMTVNTUAADA (more stuff goes here I cut it short) Host: gmail.google.com At this point the username and password prompt has appeared in the browser, it does not matter what is typed into this box, correct credentials, random nonsense the browser does not accept anything in this box it will continue to popup. If I press cancel, I sometimes get a http 407 error, but on other occasions I click cancel the website proceeds to download and show normally. This is repeatable with some clients running through my proxy server, but in other cases it does not happen at all. In the cases where a client computer works normally, the only difference I can see is that the 3rd request for SSL resource comes back with a 200 response, see below: CONNECT gmail.google.com:443 HTTP/1.0 User-Agent: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; MALC) Proxy-Connection: Keep-Alive Content-Length: 0 Host: gmail.google.com Pragma: no-cache Proxy-Authorization: NTLM TlRMTVNTUAADAAAAGAAYAIAAAA A SSLv3-compatible ClientHello handshake was found. I have tried resetting user accounts as well as computer accounts in Active Directory. User accounts and passwords that are being used are correct and the passwords have been reset so they are not out of sync. I have removed the clients and even the proxy server from the domain, and rejoined them. I have installed a complete separate proxy server and get exactly the same problem when I point clients to a different proxy server on a different IP address.

Read the article

nginx : backend https, proxy_pass shows ip

- by Vulpo

I am using nginx as a reverse proxy listening at port 80 (http). I am using proxy_pass to forward requests to backend http and https servers. Everything works fine for my http server but when I try to reach the https server through nginx reverse proxy the ip of the https server is shown in the client's web browser. I want the uri of the nginx server to be shown instead of the https backend server's ip (once again, this works fine with the http server but not for the https server). See this post on the forum Here is my configuration file : server { listen 80; server_name domain1.com; access_log off; root /var/www; if ($request_method !~ ^(GET|HEAD|POST)$ ) { return 444; } location / { proxy_pass http://ipOfHttpServer:port/; } } server { listen 80; server_name domain2.com; access_log off; root /var/www; if ($request_method !~ ^(GET|HEAD|POST)$ ) { return 444; } location / { proxy_pass http://ipOfHttpsServer:port/; proxy_set_header X_FORWARDED_PROTO https; #proxy_set_header Host $http_host; } } When I try the "proxy_set_header Host $http_host" directive and "proxy_set_header Host $host" the web page can't be reached (page not found). But when I comment it, the ip of the https server is shown in the browser (which is bad). Does anyone have an idea ? My other configs files are : proxy_redirect off; proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; #proxy_hide_header X-Powered-By; proxy_intercept_errors on; proxy_buffering on; proxy_cache_key "$scheme://$host$request_uri"; proxy_cache_path /var/cache/nginx levels=1:2 keys_zone=cache:10m inactive=7d max_size=700m; user www-data; worker_processes 2; error_log /var/log/nginx/error.log; pid /var/run/nginx.pid; events { worker_connections 1024; } http { include /etc/nginx/mime.types; default_type application/octet-stream; access_log /var/log/nginx/access.log; server_names_hash_bucket_size 64; sendfile off; tcp_nopush on; #keepalive_timeout 0; keepalive_timeout 65; tcp_nodelay on; gzip on; gzip_comp_level 5; gzip_http_version 1.0; gzip_min_length 0; gzip_types text/plain text/html text/css image/x-icon application/x-javascript; gzip_vary on; include /etc/nginx/conf.d/*.conf; include /etc/nginx/sites-enabled/*; } Thanks for your help !

Read the article

What's wrong with this vcl config for varnish-cache as load balancer?

- by dabito

I have the current configurations active on my default.vcl varnish file on the machine that balances the load for other two machines (the other two machines also have varnish active). My intention is to have this server do only the load balancing and the other machines do the processing and also their own caching. My problem is that even with the config testing (not even a stress test or anything, just a few requests a minute) I get the guru meditation error and have to restart varnish. This is the default.vcl for the load balancing server: backend vader { .host = "app1.server.com"; .probe = { .url = "/"; .interval = 10s; .timeout = 4s; .window = 5; .threshold = 3; } } backend malgus { .host = "app2.server.com"; .probe = { .url = "/"; .interval = 10s; .timeout = 4s; .window = 5; .threshold = 3; } } director dooku round-robin { { .backend = vader; } { .backend = malgus; } } sub vcl_recv { if (req.http.host ~ "^balancer.server.com$") { set req.backend = dooku; } } Am I doing something wrong or missing something? EDIT: This is varnishlog's output: 0 CLI - Rd ping 0 CLI - Wr 200 19 PONG 1345839995 1.0 0 CLI - Rd ping 0 CLI - Wr 200 19 PONG 1345839998 1.0 0 CLI - Rd ping 0 CLI - Wr 200 19 PONG 1345840001 1.0 0 Backend_health - malgus Still sick 4--X--- 0 3 5 0.000000 3.846876 0 Backend_health - vader Still sick 4--X--- 0 3 5 0.000000 3.839194 0 CLI - Rd ping 0 CLI - Wr 200 19 PONG 1345840004 1.0 14 SessionOpen c 10.150.7.151 38272 :80 14 ReqStart c 10.150.7.151 38272 458200540 14 RxRequest c GET 14 RxURL c / 14 RxProtocol c HTTP/1.1 14 RxHeader c Host: dooku-dev.excelsior.com 14 RxHeader c Connection: keep-alive 14 RxHeader c User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11 14 RxHeader c Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 14 RxHeader c Accept-Encoding: gzip,deflate,sdch 14 RxHeader c Accept-Language: en-US,en;q=0.8,es-419;q=0.6,es;q=0.4 14 RxHeader c Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3 14 RxHeader c Cookie: SESSa87d6c6da0c61037a9169122dc5e4a19=HR_0Srhgc-uDArT3aJFzOBy31FtzneTXg38byr1eGMU; __atuvc=4%7C33 14 VCL_call c recv pass 14 VCL_call c hash 14 Hash c / 14 Hash c dooku-dev.excelsior.com 14 VCL_return c hash 14 VCL_call c pass pass 14 FetchError c no backend connection 14 VCL_call c error deliver 14 VCL_call c deliver deliver 14 TxProtocol c HTTP/1.1 14 TxStatus c 503 14 TxResponse c Service Unavailable 14 TxHeader c Server: Varnish 14 TxHeader c Content-Type: text/html; charset=utf-8 14 TxHeader c Retry-After: 5 14 TxHeader c Content-Length: 418 14 TxHeader c Accept-Ranges: bytes 14 TxHeader c Date: Fri, 24 Aug 2012 20:26:44 GMT 14 TxHeader c X-Varnish: 458200540 14 TxHeader c Age: 0 14 TxHeader c Via: 1.1 varnish 14 TxHeader c Connection: close 14 Length c 418 14 ReqEnd c 458200540 1345840004.916415691 1345840004.965190172 0.020933390 0.048741817 0.000032663 14 SessionClose c error 14 StatSess c 10.150.7.151 38272 0 1 1 0 1 0 256 418 14 SessionOpen c 10.150.7.151 38273 :80 14 ReqStart c 10.150.7.151 38273 458200541 14 RxRequest c GET 14 RxURL c /favicon.ico 14 RxProtocol c HTTP/1.1 14 RxHeader c Host: dooku-dev.excelsior.com 14 RxHeader c Connection: keep-alive 14 RxHeader c Accept: */* 14 RxHeader c User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11 14 RxHeader c Accept-Encoding: gzip,deflate,sdch 14 RxHeader c Accept-Language: en-US,en;q=0.8,es-419;q=0.6,es;q=0.4 14 RxHeader c Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3 14 RxHeader c Cookie: SESSa87d6c6da0c61037a9169122dc5e4a19=HR_0Srhgc-uDArT3aJFzOBy31FtzneTXg38byr1eGMU; __atuvc=4%7C33 14 VCL_call c recv pass 14 VCL_call c hash 14 Hash c /favicon.ico 14 Hash c dooku-dev.excelsior.com 14 VCL_return c hash 14 VCL_call c pass pass 14 FetchError c no backend connection 14 VCL_call c error deliver 14 VCL_call c deliver deliver 14 TxProtocol c HTTP/1.1 14 TxStatus c 503 14 TxResponse c Service Unavailable 14 TxHeader c Server: Varnish 14 TxHeader c Content-Type: text/html; charset=utf-8 14 TxHeader c Retry-After: 5 14 TxHeader c Content-Length: 418 14 TxHeader c Accept-Ranges: bytes 14 TxHeader c Date: Fri, 24 Aug 2012 20:26:45 GMT 14 TxHeader c X-Varnish: 458200541 14 TxHeader c Age: 0 14 TxHeader c Via: 1.1 varnish 14 TxHeader c Connection: close 14 Length c 418 14 ReqEnd c 458200541 1345840005.226389885 1345840005.226457834 0.000026941 0.000043154 0.000024796 14 SessionClose c error 14 StatSess c 10.150.7.151 38273 0 1 1 0 1 0 256 418

Read the article

duplicate cache pages: Varnish

- by Sukhjinder Singh

Recently we have configured Varnish on our server, it was successfully setup but we noticed that if we open any page in multiple browsers, the Varnish send request to Apache not matter page is cached or not. If we refresh twice on each browser it creates duplicate copies of the same page. What exactly should happen: If any page is cached by Varnish, the subsequent request should be served from Varnish itself when we are opening the same page in browser OR we are opening that page from different IP address. Following is my default.vcl file backend default { .host = "127.0.0.1"; .port = "80"; } sub vcl_recv { if( req.url ~ "^/search/.*$") { }else { set req.url = regsub(req.url, "\?.*", ""); } if (req.restarts == 0) { if (req.http.x-forwarded-for) { set req.http.X-Forwarded-For = req.http.X-Forwarded-For + ", " + client.ip; } else { set req.http.X-Forwarded-For = client.ip; } } if (!req.backend.healthy) { unset req.http.Cookie; } set req.grace = 6h; if (req.url ~ "^/status\.php$" || req.url ~ "^/update\.php$" || req.url ~ "^/admin$" || req.url ~ "^/admin/.*$" || req.url ~ "^/flag/.*$" || req.url ~ "^.*/ajax/.*$" || req.url ~ "^.*/ahah/.*$") { return (pass); } if (req.url ~ "(?i)\.(pdf|asc|dat|txt|doc|xls|ppt|tgz|csv|png|gif|jpeg|jpg|ico|swf|css|js)(\?.*)?$") { unset req.http.Cookie; } if (req.http.Cookie) { set req.http.Cookie = ";" + req.http.Cookie; set req.http.Cookie = regsuball(req.http.Cookie, "; +", ";"); set req.http.Cookie = regsuball(req.http.Cookie, ";(SESS[a-z0-9]+|SSESS[a-z0-9]+|NO_CACHE)=", "; \1="); set req.http.Cookie = regsuball(req.http.Cookie, ";[^ ][^;]*", ""); set req.http.Cookie = regsuball(req.http.Cookie, "^[; ]+|[; ]+$", ""); if (req.http.Cookie == "") { unset req.http.Cookie; } else { return (pass); } } if (req.request != "GET" && req.request != "HEAD" && req.request != "PUT" && req.request != "POST" && req.request != "TRACE" && req.request != "OPTIONS" && req.request != "DELETE") {return(pipe);} /* Non-RFC2616 or CONNECT which is weird. */ if (req.request != "GET" && req.request != "HEAD") { return (pass); } if (req.http.Accept-Encoding) { if (req.url ~ "\.(jpg|png|gif|gz|tgz|bz2|tbz|mp3|ogg)$") { # No point in compressing these remove req.http.Accept-Encoding; } else if (req.http.Accept-Encoding ~ "gzip") { set req.http.Accept-Encoding = "gzip"; } else if (req.http.Accept-Encoding ~ "deflate") { set req.http.Accept-Encoding = "deflate"; } else { # unknown algorithm remove req.http.Accept-Encoding; } } return (lookup); } sub vcl_deliver { if (obj.hits > 0) { set resp.http.X-Varnish-Cache = "HIT"; } else { set resp.http.X-Varnish-Cache = "MISS"; } } sub vcl_fetch { if (beresp.status == 404 || beresp.status == 301 || beresp.status == 500) { set beresp.ttl = 10m; } if (req.url ~ "(?i)\.(pdf|asc|dat|txt|doc|xls|ppt|tgz|csv|png|gif|jpeg|jpg|ico|swf|css|js)(\?.*)?$") { unset beresp.http.set-cookie; } set beresp.grace = 6h; } sub vcl_hash { hash_data(req.url); if (req.http.host) { hash_data(req.http.host); } else { hash_data(server.ip); } return (hash); } sub vcl_pipe { set req.http.connection = "close"; } sub vcl_hit { if (req.request == "PURGE") {ban_url(req.url); error 200 "Purged";} if (!obj.ttl > 0s) {return(pass);} } sub vcl_miss { if (req.request == "PURGE") {error 200 "Not in cache";} }

Search Results

Search found 23449 results on 938 pages for 'browser close'.

Page 461/938 | < Previous Page | 457 458 459 460 461 462 463 464 465 466 467 468 | Next Page >

- by breez

- by d9k

- by fx

- by iefpw

- by Anirudh Goel

- by Crimson

- by Rick Strahl

- by Shaun

- by azat

- by Dennis Gorelik

- by Yaniro

- by Andy Leman

- by Reinderien

- by Tom Lagier

- by T.J. Crowder

- by Luca

- by johnlai2004

- by Michael Graff

- by Blaenk

- by CyberShadow

- by Pantelis Sopasakis

- by Marko

- by Vulpo

- by dabito

- by Sukhjinder Singh

< Previous Page | 457 458 459 460 461 462 463 464 465 466 467 468 | Next Page >