Search Results

Search found 20990 results on 840 pages for 'static block'.

Page 24/840 | < Previous Page | 20 21 22 23 24 25 26 27 28 29 30 31  | Next Page >

• Ext3 fs: Block bitmap for group 1 not in group (block 0). is fs dead?

  - by ip

  My company has a server with one big partition with Mysql database and php files. Now this partition seems to be corrupted, as reported from kernel messages when I tried to mount it manually: [329862.817837] EXT3-fs error (device loop1): ext3_check_descriptors: Block bitmap for group 1 not in group (block 0)! [329862.817846] EXT3-fs: group descriptors corrupted! I've tried to recovery it running tools from a PLD livecd. These are the tools I have tested: - e2retrieve - testdisk - photorec - dd_rescue/dd_rhelp - ddrescue - fsck.ext2 - e2salvage without any success. dumpe2fs 1.41.3 (12-Oct-2008) Filesystem volume name: /dev/sda3 Last mounted on: <not available> Filesystem UUID: dd51610b-6de0-4392-a6f3-67160dbc0343 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal filetype sparse_super Default mount options: (none) Filesystem state: not clean with errors Errors behavior: Continue Filesystem OS type: Linux Inode count: 9502720 Block count: 18987570 Reserved block count: 949378 Free blocks: 11555345 Free inodes: 11858398 First block: 0 Block size: 4096 Fragment size: 4096 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 16384 Inode blocks per group: 512 Last mount time: Wed Mar 24 09:31:03 2010 Last write time: Mon Apr 12 11:46:32 2010 Mount count: 10 Maximum mount count: 30 Last checked: Thu Jan 1 01:00:00 1970 Check interval: 0 (<none>) Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 128 Journal inode: 8 Journal backup: inode blocks dumpe2fs: A block group is missing an inode table while reading journal inode e2fsck 1.41.3 (12-Oct-2008) fsck.ext3: Group descriptors look bad... trying backup blocks... fsck.ext3: A block group is missing an inode table while checking ext3 journal for /dev/sda3 I tried also backup superblocks, same error result. There's any other tools I have to test before considering these disk definitely unrecoverable? Many thanks, ip

  Read the article

• Publish Static Content to WebLogic

  - by James Taylor

  Most people know WebLogic has a built in web server. Typically this is not an issue as you deploy java applications and WebLogic publishes to the web. But what if you just want to display a simple static HTML page. In WebLogic you can develop a simple web application to display static HTML content. In this example I used WLS 10.3.3. I want to display 2 files, an HTML file, and an xsd for reference. Create a directory of your choice, this is what I will call the document root. mkdir /u01/oracle/doc_root Copy the static files to this directory  In the document root directory created in step 1 create the directory WEB-INF mkdir WEB-INF In the WEB-INF directory create a file called web.xml with the following content <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/j2ee/dtds/web-app_2_3.dtd"> <web-app> </web-app> Login to the WebLogic console to deploy application Click on Deployments Click on Lock & Edit Click Install and set the path to the directory created in step 1 Leave default "Install this deployment as an application" and click Next Select a Managed Server to deploy to and click Next Accept the defaults and click Finish  Deployment completes successfully, now click the Activate Changes You should now see the application started in the deployments You can now access your static content via the following URL http://localhost:7001/doc_root/helloworld.html

  Read the article

• Managing JS and CSS for a static HTML web application

  - by Josh Kelley

  I'm working on a smallish web application that uses a little bit of static HTML and relies on JavaScript to load the application data as JSON and dynamically create the web page elements from that. First question: Is this a fundamentally bad idea? I'm unclear on how many web sites and web applications completely dispense with server-side generation of HTML. (There are obvious disadvantages of JS-only web apps in the areas of graceful degradation / progressive enhancement and being search engine friendly, but I don't believe that these are an issue for this particular app.) Second question: What's the best way to manage the static HTML, JS, and CSS? For my "development build," I'd like non-minified third-party code, multiple JS and CSS files for easier organization, etc. For the "release build," everything should be minified, concatenated together, etc. If I was doing server-side generation of HTML, it'd be easy to have my web framework generate different development versus release HTML that includes multiple verbose versus concatenated minified code. But given that I'm only doing any static HTML, what's the best way to manage this? (I realize I could hack something together with ERB or Perl, but I'm wondering if there are any standard solutions.) In particular, since I'm not doing any server-side HTML generation, is there an easy, semi-standard way of setting up my static HTML so that it contains code like <script src="js/vendors/jquery.js"></script> <script src="js/class_a.js"></script> <script src="js/class_b.js"></script> <script src="js/main.js"></script> at development time and <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script> <script src="js/entire_app.min.js"></script> for release?

  Read the article

• Installing Oracle Block Browser and Editor tool (bbed)

  What if you could directly read and manipulate data at the block level? Oracle provides such a tool to do exactly that, but you have to build it yourself. The Block Browser and Editor tool, or bbed for short, is your ticket into the contents of data blocks within an Oracle database.

  Read the article

• Add static ARP entries when network is brought up

  - by jozzas

  I have some pretty dumb IP devices on a subnet with my Ubuntu server, and the server receives streaming data from each device. I have run into a problem in that when an ARP request is issued to the device while it is streaming data to the server, the request is ignored, the cache entry times out and the server stops receiving the stream. So, to prevent the server from sending ARP requests to these devices altogether, I would like to add a static ARP entry for each, something like arp -i eth2 -s ip.of.the.device mac:of:the:device But these "static" ARP entries are lost if networking is disabled / enabled or if the server is rebooted. Where is the best place to automatically add these entries, preferably somewhere that will re-add them every time the interface eth2 is brought up? I really don't want to have to write a script that monitors the output of arp and re-adds the cache entries if they're missing. Edit to add what my final script was: Created the file /etc/network/if-up.d/add-my-static-arp With the contents: #!/bin/sh arp -i eth0 -s 192.168.0.4 00:50:cc:44:55:55 arp -i eth0 -s 192.168.0.5 00:50:cc:44:55:56 arp -i eth0 -s 192.168.0.6 00:50:cc:44:55:57 And then obviously add the permission to allow it to be executed: chmod +x /etc/network/if-up.d/add-my-static-arp And these arp entries will be manually added or re-added every time any network interface is brought up.

  Read the article

• drupal - using variable_set, hook block and hook menu to save config values then print out in custom

  - by bert

  I am trying to 1) implement the hook menu and variable_set in the block hook and to solicit and store configuration values from user, 2) then use retrieve configuration values and 3) pass them out into a template using theme hook when page is shown. However I need a bit of a push on step two and three! // ===================== file: my_module.php function my_module_block($op = 'list', $delta = 0, $edit = array()) { switch($op) { case 'list': $blocks[0] = array( 'info' => t('Find Something'), // required value - this shows up in your list of blocks 'region' => 'left', // default region on the page 'weight' => 0, // position the block vertically within its column. 'visibility' => 1, // permit the block to be displayed for a given user. 'status' => TRUE, // enabled ); return $blocks; break; // case configure case 'configure': // not used ? // case save (save configuration values) case 'save': variable_set('my_module_text_bottom', $edit['my_module_text_bottom']); variable_set('my_module_text_top', $edit['my_module_text_top']); break; } } function my_module_menu(){ $items = array(); // add menu items $items['my_module'] = array( // add a menu item here... ); // administration setting - callback my_module_admin $items['admin/settings/my_module'] = array( 'title' => 'Lookup on Something', 'description' => 'Description of my module settings page', 'page callback' => 'drupal_get_form', 'page arguments' => array('my_module_admin'), 'access arguments' => array('access administration pages'), 'type' => MENU_NORMAL_ITEM, ); return $items; } // setup administrative default values (see: site configiration) function my_module_admin() { $form = array(); $form['my_module_text_top'] = array( '#type' => 'textarea', '#title' => t('Text of top of page'), '#default_value' => variable_get('my_module_text_top', 'my_module_text_top: This is configurable text found in the module configuration.'), '#size' => 1024, '#maxlength' => 1024, '#description' => t("text above the Find a Retailer block."), '#required' => TRUE, ); $form['my_module_text_bottom'] = array( '#type' => 'textarea', '#title' => t('Text at bottom of page'), '#default_value' => variable_get('my_module_text_bottom', 'my_module_text_bottom: This is configurable text found in the module configuration.'), '#size' => 1024, '#maxlength' => 1024, '#description' => t("text below the Find a Retailer block."), '#required' => TRUE, ); return system_settings_form($form); } // registering a theme function my_module_theme(){ return array( 'my_module_show' => array( 'arguments' => array('content' => "hello"), 'template' => 'my_module_show' ), ); } // implementing a theme function theme_my_module_show($content){ $output = '<ul>$content</ul>'; return $output; } function my_module(){ $output = ''; $variables = ""; $output .= theme('my_module_show', $variables); return $output; } // ===================== file: my_module_show.tpl.php print $text1; print $text2;

  Read the article

• get_called_class hack not working with eval-code.

  - by Ekampp

  Hi there. I am using a ge_called_class hack for allowing late static binding in php version 5.2 (found here). I have the following in my code: # db_record.php $ac = "ForumThread"; $objects = $ac::find("all"); This will not work in php 5.2 for some reason, so I have done this: # db_record.php $ac = "ForumThread"; eval("\$objects = {$ac}::find('all');"); This on the other hand will not work with the get_called_class function. I get an error that the file function can't read the evaled section of code. So how do I solve this problem? Best regards.

  Read the article

• Compilation Error related

  - by aparna

  Given: 11. public static void test(String str) { 12. int check = 4; 13. if (check = str.length()) { 14. System.out.print(str.charAt(check -= 1) +", "); 15. } else { 16. System.out.print(str.charAt(0) + ", "); 17. } 18. } and the invocation: 21. test("four"); 22. test("tee"); 23. test("to"); What is the result? A. r, t, t, B. r, e, o, C. Compilation fails. D. An exception is thrown at runtime. Answer: C Can you explain why the compilation fails please?

  Read the article

• problem on static link to libsmbclient.a

  - by Rex

  I've tried to develop a library using libsmbclient-dev to access net share folders. I wish to static link libsmbclient.a in my project , but a lot of error happens when I tried to static link it, it seems that the libsmbclient.a doesn't include some objects it needed , while everything goes well with libsmbclient.so. Because my project need to support various linux versions like centOS , Ubuntu ..., we wish not to install libsmbclient-dev everywhere. Can anybody tell me that if I can static link this libsmbclient.a in an easy way ? Or what kind of installation strategy should I take to cause less trouble to users? If anyone have use this library to develop projects before , can you tell me how you deal with this case? Thank you very much!!!

  Read the article

• Naming convention: Final fields (not static)

  - by Zeeker

  Today I had a discussion with a co-worker about the naming of final fields in Java classes. In his opionion final fields should also be considered constants since their values won't change after the creation of the instance. This would lead to the following naming convention for final fields: public class Foo { private static final String BLA_BLA = "bla"; private final String BAR_BATZ; ... } In my opinion only static final fields should be considered constants while fields which are only final should follow the usual camelCase naming convention. public class Foo { private static final String BLA = "bla"; private final String barBatz; ... } Now I'm a bit uncertain since he is a far more experienced programmer than I am and I usually agree with his opinions and consider him a very good developer. Any input on this?

  Read the article

• Resuming from hibernation shows a fuzzy "static" screen

  - by Ross

  When I resume from hibernation in Ubuntu 10.10 the screen shows static, very similar to what you see on an analogue TV that hasn't been tuned properly. This also occurs on boot from shut down, but only for a moment after the Plymouth boot screen. The static lasts for at least 5 minutes. An odd thing that happens is that the mouse pointer, as a lighter square of static, becomes visible and you can move it around. Attempting to change into a terminal (i.e. Ctrl+Alt+F1) doesn't seem to work (and I'm not sure if that can be done from the login screen). Resuming from suspend has different issues - vertical lines appearing for a second before appearing to be in terminal mode (blinking cursor) and then going to the lock screen. I'm running Ubuntu 10.10 on a Dell Studio 15 with ATI graphics, however I'm not using the proprietary drivers as I had issues with dual-screen support, so it's the generic X.org drivers being used.

  Read the article

• does class reference itself static anti pattern in prism

  - by Michael Riva

  I have an application and my desing approach look like this: class Manager { public int State; static Manager _instance = null; public static Manager Instance { get { return _instance; } set { if (_instance == value) return; _instance = value; } } public Manager() { State = 0; Instance=this; } } class Module1 { public void GetState() { Console.WriteLine(Manager.Instance.State); } } class Module2 { public void GetState() { Console.WriteLine(Manager.Instance.State); } } class Module3 { public void GetState() { Console.WriteLine(Manager.Instance.State); } } Manager class already registered in Bootstrapper like : protected override void ConfigureContainer() { base.ConfigureContainer(); Container.RegisterType<Manager>(new ContainerControlledLifetimeManager()); } protected override void InitializeModules() { Manager man= Container.Resolve<Manager>(); } Question is do I need to define my manager object as static in its field to be able to reach its state? Or this is anti pattern or bad for performance?

  Read the article

• using static methods and classes

  - by vedant1811

  I know that static methods/variables are associated with the class and not the objects of the class and are useful in situations when we need to keep count of, say the number of objects of the class that were created. Non-static members on the other hand may need to work on the specific object (i.e. to use the variables initialized by the constructor) My question what should we do when we need neither of the functionalities? Say I just need a utility function that accepts value(s) and returns a value besed solely on the values passed. I want to know whether such methods should be static or not. How is programming efficiency affected and which is a better coding practice/convention and why. PS: I don't want to spark off a debate, I just want a subjective answer and/or references.

  Read the article

• How do you code up a pattern matching block in scala?

  - by egervari

  How do you code a function that takes in a block of code that contains case statements? For instance, in my block of code, I don't want to code a match or a default case... looking something like this myApi { case Whatever() => // code for case 1 case SomethingElse() => // code for case 2 } And inside of my myApi(), it'll actually do the matches. Help?

  Read the article

• how many processors can I get in a block on cuda GPU?

  - by Vickey

  hi all, I have two questions to ask 1) If I create only one block of threads in cuda and execute the my parallel program on it then is it possible that more than one processors would be given to single block so that my program get some benefit of multiprocessor platform ? 2) can I synchronize the threads of different blocks ? if yes please give some hints. Thanks in advance since I know I'll get replies as always I get.

  Read the article

• How to block/avoid a particular IP when connecting to websites?

  - by Mark

  I'm having trouble connecting to a particular website. I can view it through a proxy, but not from home. So I ran a traceroute: Tracing route to fvringette.com [76.74.225.90] over a maximum of 30 hops: 1 <1 ms <1 ms <1 ms <snip> 2 * * * Request timed out. 3 9 ms 7 ms 27 ms rd2bb-ge2-0-0-22.vc.shawcable.net [64.59.146.226] 4 8 ms 7 ms 7 ms rc2bb-tge0-9-2-0.vc.shawcable.net [66.163.69.41] 5 10 ms 9 ms 9 ms rc2wh-tge0-0-1-0.vc.shawcable.net [66.163.69.65] 6 27 ms 23 ms 22 ms ge-gi0-2.pix.van.peer1.net [206.223.127.1] 7 18 ms 18 ms 20 ms 10ge.xe-0-2-0.van-spenc-dis-1.peer1.net [216.187.89.206] 8 9 ms 11 ms 10 ms 64.69.91.245 9 * * * Request timed out. 10 * * * Request timed out. ... Looks like this "64.69.91.245" is somehow blocking me. Can I tell my computer to avoid/bypass that IP when trying to connect?

  Read the article

• How to route outbound traffic to specific domain "XYZ.org" via a specific NIC or public/static IP?

  - by user139943

  Within the next week or so, I'll be setting up an AT&T U-verse modem with 5 usable static public IP addresses. I plan to register a domain name to 1 of the 5 static IPs (remaining 4 unregistered), and run a website from a single server setup in my home LAN. I'll skip the long winded reason why, but I need to somehow route outbound traffic (originating from my server) destined for one public domain (i.e. http://www.sample.org) through one of the UNREGISTERED static IP addresses ONLY. Basically, I want this public domain to see connections coming from an IP address and not my domain name. If it makes it easier, this can apply to all outbound traffic from my server as long as it doesn't impact users browsing my website! Inbound connections should go through the domain name / registered public IP. Can I accomplish this with my single server with one or multiple NICs? Do I need multiple servers and set one up as a proxy? Please help as my background is in software and not networking, and I don't think I can accomplish this at a software level (e.g. Java). Thanks.

  Read the article

• C# Proposal: Compile Time Static Checking Of Dynamic Objects

  - by Paulo Morgado

  C# 4.0 introduces a new type: dynamic. dynamic is a static type that bypasses static type checking. This new type comes in very handy to work with: The new languages from the dynamic language runtime. HTML Document Object Model (DOM). COM objects. Duck typing … Because static type checking is bypassed, this: dynamic dynamicValue = GetValue(); dynamicValue.Method(); is equivalent to this: object objectValue = GetValue(); objectValue .GetType() .InvokeMember( "Method", BindingFlags.InvokeMethod, null, objectValue, null); Apart from caching the call site behind the scenes and some dynamic resolution, dynamic only looks better. Any typing error will only be caught at run time. In fact, if I’m writing the code, I know the contract of what I’m calling. Wouldn’t it be nice to have the compiler do some static type checking on the interactions with these dynamic objects? Imagine that the dynamic object that I’m retrieving from the GetValue method, besides the parameterless method Method also has a string read-only Property property. This means that, from the point of view of the code I’m writing, the contract that the dynamic object returned by GetValue implements is: string Property { get; } void Method(); Since it’s a well defined contract, I could write an interface to represent it: interface IValue { string Property { get; } void Method(); } If dynamic allowed to specify the contract in the form of dynamic(contract), I could write this: dynamic(IValue) dynamicValue = GetValue(); dynamicValue.Method(); This doesn’t mean that the value returned by GetValue has to implement the IValue interface. It just enables the compiler to verify that dynamicValue.Method() is a valid use of dynamicValue and dynamicValue.OtherMethod() isn’t. If the IValue interface already existed for any other reason, this would be fine. But having a type added to an assembly just for compile time usage doesn’t seem right. So, dynamic could be another type construct. Something like this: dynamic DValue { string Property { get; } void Method(); } The code could now be written like this; DValue dynamicValue = GetValue(); dynamicValue.Method(); The compiler would never generate any IL or metadata for this new type construct. It would only thee used for compile type static checking of dynamic objects. As a consequence, it makes no sense to have public accessibility, so it would not be allowed. Once again, if the IValue interface (or any other type definition) already exists, it can be used in the dynamic type definition: dynamic DValue : IValue, IEnumerable, SomeClass { string Property { get; } void Method(); } Another added benefit would be IntelliSense. I’ve been getting mixed reactions to this proposal. What do you think? Would this be useful?

  Read the article

• Creating block devices for openstack deployment using MAAS and juju (nova-volume deployment)

  - by Tom Van Hoof

  Hi, I'm currently trying to get a openstack deployment working by using MAAS with 9 nodes and juju. To do this I found this guide, working with ubuntu 12.04 LTS https://help.ubuntu.com/community/UbuntuCloudInfrastructure and followed it as good as I can. After a vigorous amount of trial and error I finally got to the point where I'm supposed to deploy nova-volume using the "custom" config file. However when my node is started and shows up as running in the "juju status" report the service reports the installation failed. I'm trying to install with juju jitsu by the way. I think it has something to do with the following statement in the openstack.cfg file : nova-volume: # This must be a free block device that is writable on the nova-volume host. block-device: "xvdb" overwrite: "true" I did some research and found that (at least I think) this refers to a Xen Virtual Drive/device, and because the device is not present on the node it's being deployed to, the installation fails. What I don't understand is how I am supposed to have such a block device available on a machine which was completely managed by MAAS. Does anyone here have any experience with this and knows of a way to solve this, or am I missing something big here. Some kind of missing link between the MAAS and a separate XEN host ? My MAAS server is ubuntu 12.04LTS Server. All help is welcome. Kind regards, Tom

  Read the article

• How do i make an AJAX block crawlable?

  - by Vikas Gulati

  I have a block with a few tabs. When the user clicks the tab the content of that block get loaded. Now I would like to make it crawlable by the search engines and at the same time I want to maintain the good user-experience. I figured out a couple of alternative but each one has its own shortcomings. The approached that i could come up with. Use hashbangs and then use this. But hashbangs are not good and things of past now. Secondly it will make my content crawlable by only googlebot as yahoo and bing dont support this. Use GET PARAMETERIZED fallback incase when javascript doesn't work. This will work for all bots and also would be nice as it would work without javascript. But then this will create duplicates of my page as this block is only a very small section of my page and i have like around 5-6 tabs. So it means that many duplicates! Doing this without AJAX is not an option as it would only increase the page load time as all these blocks have heavy media content in them!

  Read the article

• MVC Portable Areas &ndash; Deploying Static Files

  - by Steve Michelotti

  This is the second post in a series related to build and deployment considerations as I’ve been exploring MVC Portable Areas: #1 – Using Web Application Project to build portable areas #2 – Conventions for deploying portable area static files #3 – Portable area static files as embedded resources As I’ve been digging more into portable areas, one of the things I’ve liked best is the deployment story which enables my *.aspx, *.ascx pages to be compiled into the assembly as embedded resources rather than having to maintain all those files separately. In traditional web forms, that was always the thing to prevented developers from utilizing *.ascx user controls across projects (see this post for using portable areas in web forms).  However, though the aspx pages are embedded, the supporting static files (e.g., images, css, javascript) are *not*. Most of the demos available online today tend to brush over this issue and focus solely on the aspx side of things. But to create truly robust portable areas, it’s important to have a good story for these supporting files as well.  I’ve been working with two different approaches so far (of course I’d really like to hear if other people are using alternatives). Scenario For the approaches below, the scenario really isn’t that important. It could be something as trivial as this partial view: 1: <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %> 2: <img src="<%: Url.Content("~/images/arrow.gif") %>" /> Hello World! The point is that there needs to be careful consideration for *any* scenario that links to an external file such as an image, *.css, *.js, etc. In the example shown above, it uses the Url.Content() method to convert to a relative path. But this method won’t necessary work depending on how you deploy your portable area. One approach to address this issue is to build your portable area project with MSDeploy/WebDeploy so that it is packaged properly before incorporating into the host application. All of the *.cs files are removed and the project is ready for xcopy deployment – however, I do *not* need the “Views” folder since all of the mark up has been compiled into the assembly as embedded resources. Now in the host application we create a folder called “Modules” and deploy any portable areas as sub-folders under that: At this point we can add a simple assembly reference to the Widget1.dll sitting in the Modules\Widget1\bin folder. I can now render the portable image in my view like any other portable area. However, the problem with that is that the view results in this:   It couldn’t find arrow.gif because it looked for /images/arrow.gif and it was *actually* located at /images/Modules/Widget1/images/arrow.gif. One solution is to make the physical location of the portable configurable from the perspective of the host like this: 1: <appSettings> 2: <add key="Widget1" value="Modules\Widget1"/> 3: </appSettings> Using the <appSettings> section is a little cheesy but it could be better formalized into its own section. In fact, if were you willing to rely on conventions (e.g., “Modules\{areaName}”) then then config could be eliminated completely. With this config in place, we could create our own Html helper method called Url.AreaContent() that “wraps” the OOTB Url.Content() method while simply pre-pending the area location path: 1: public static string AreaContent(this UrlHelper urlHelper, string contentPath) 2: { 3: var areaName = (string)urlHelper.RequestContext.RouteData.DataTokens["area"]; 4: var areaPath = (string)ConfigurationManager.AppSettings[areaName]; 5:   6: return urlHelper.Content("~/" + areaPath + "/" + contentPath); With these two items in place, we just change our Url.Content() call to Url.AreaContent() like this: 1: <img src="<%: Url.AreaContent("/images/arrow.gif") %>" /> Hello World! and the arrow.gif now renders correctly:     Since we’re just using our own Url.AreaContent() rather than the built-in Url.Content(), this solution works for images, *.css, *.js, or any externally referenced files.  Additionally, any images referenced inside a css file will work provided it’s a relative reference and not an absolute reference. An alternative to this approach is to build the static file into the assembly as embedded resources themselves. I’ll explore this in another post (linked at the top).

  Read the article

• Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block 0,0

  - by AlbertK

  I've read the following two solution: Kernel Panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) kernel panic not syncing vfs unable to mount root fs on unknown block oo swapper not tainted ,but still got the same problem. Here's my full error code: [1.902269] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) [1.902299] Pid: 1, comm: swapper/0 Not tainted 3.2.0-29-generic #46-Ubuntu [1.902325] Call Trace: [1.902348] [<ffffffff81640ec8>] panic+0x91/0x1a4 [1.902373] [<ffffffff81cfc01e>] mount_block_root+0xdc/0x18e [1.902400] [<ffffffff81002930>] ? populate_rootfs_wait+0x300/0x9d0 [1.902426] [<ffffffff81cfc257>] mount_root+0x54/0x59 [1.902450] [<ffffffff81cfc3c9>] prepare_namespace+0x16d/0x1a6 [1.902476] [<ffffffff81cfbd63>] kernel_init+0x153/0x158 [1.902501] [<ffffffff81664034>] kernel_thread_helper+0x4/0x10 [1.902527] [<ffffffff81cfbc10>] ? start_kernel+0x3bd/0x3bd [1.902551] [<ffffffff81664030>] ? gs_change+0x13/0x13 I don't know what these error messages mean at all, but I hope that these will help to solve this problem I'm running Ubuntu 12.04. Thanks for any advice.

  Read the article

• C#/.NET Little Wonders: The Nullable static class

  - by James Michael Hare

  Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Today we’re going to look at an interesting Little Wonder that can be used to mitigate what could be considered a Little Pitfall.  The Little Wonder we’ll be examining is the System.Nullable static class.  No, not the System.Nullable<T> class, but a static helper class that has one useful method in particular that we will examine… but first, let’s look at the Little Pitfall that makes this wonder so useful. Little Pitfall: Comparing nullable value types using <, >, <=, >= Examine this piece of code, without examining it too deeply, what’s your gut reaction as to the result? 1: int? x = null; 2:  3: if (x < 100) 4: { 5: Console.WriteLine("True, {0} is less than 100.", 6: x.HasValue ? x.ToString() : "null"); 7: } 8: else 9: { 10: Console.WriteLine("False, {0} is NOT less than 100.", 11: x.HasValue ? x.ToString() : "null"); 12: } Your gut would be to say true right?  It would seem to make sense that a null integer is less than the integer constant 100.  But the result is actually false!  The null value is not less than 100 according to the less-than operator. It looks even more outrageous when you consider this also evaluates to false: 1: int? x = null; 2:  3: if (x < int.MaxValue) 4: { 5: // ... 6: } So, are we saying that null is less than every valid int value?  If that were true, null should be less than int.MinValue, right?  Well… no: 1: int? x = null; 2:  3: // um... hold on here, x is NOT less than min value? 4: if (x < int.MinValue) 5: { 6: // ... 7: } So what’s going on here?  If we use greater than instead of less than, we see the same little dilemma: 1: int? x = null; 2:  3: // once again, null is not greater than anything either... 4: if (x > int.MinValue) 5: { 6: // ... 7: } It turns out that four of the comparison operators (<, <=, >, >=) are designed to return false anytime at least one of the arguments is null when comparing System.Nullable wrapped types that expose the comparison operators (short, int, float, double, DateTime, TimeSpan, etc.).  What’s even odder is that even though the two equality operators (== and !=) work correctly, >= and <= have the same issue as < and > and return false if both System.Nullable wrapped operator comparable types are null! 1: DateTime? x = null; 2: DateTime? y = null; 3:  4: if (x <= y) 5: { 6: Console.WriteLine("You'd think this is true, since both are null, but it's not."); 7: } 8: else 9: { 10: Console.WriteLine("It's false because <=, <, >, >= don't work on null."); 11: } To make matters even more confusing, take for example your usual check to see if something is less than, greater to, or equal: 1: int? x = null; 2: int? y = 100; 3:  4: if (x < y) 5: { 6: Console.WriteLine("X is less than Y"); 7: } 8: else if (x > y) 9: { 10: Console.WriteLine("X is greater than Y"); 11: } 12: else 13: { 14: // We fall into the "equals" assumption, but clearly null != 100! 15: Console.WriteLine("X is equal to Y"); 16: } Yes, this code outputs “X is equal to Y” because both the less-than and greater-than operators return false when a Nullable wrapped operator comparable type is null.  This violates a lot of our assumptions because we assume is something is not less than something, and it’s not greater than something, it must be equal.  So keep in mind, that the only two comparison operators that work on Nullable wrapped types where at least one is null are the equals (==) and not equals (!=) operators: 1: int? x = null; 2: int? y = 100; 3:  4: if (x == y) 5: { 6: Console.WriteLine("False, x is null, y is not."); 7: } 8:  9: if (x != y) 10: { 11: Console.WriteLine("True, x is null, y is not."); 12: } Solution: The Nullable static class So we’ve seen that <, <=, >, and >= have some interesting and perhaps unexpected behaviors that can trip up a novice developer who isn’t expecting the kinks that System.Nullable<T> types with comparison operators can throw.  How can we easily mitigate this? Well, obviously, you could do null checks before each check, but that starts to get ugly: 1: if (x.HasValue) 2: { 3: if (y.HasValue) 4: { 5: if (x < y) 6: { 7: Console.WriteLine("x < y"); 8: } 9: else if (x > y) 10: { 11: Console.WriteLine("x > y"); 12: } 13: else 14: { 15: Console.WriteLine("x == y"); 16: } 17: } 18: else 19: { 20: Console.WriteLine("x > y because y is null and x isn't"); 21: } 22: } 23: else if (y.HasValue) 24: { 25: Console.WriteLine("x < y because x is null and y isn't"); 26: } 27: else 28: { 29: Console.WriteLine("x == y because both are null"); 30: } Yes, we could probably simplify this logic a bit, but it’s still horrendous!  So what do we do if we want to consider null less than everything and be able to properly compare Nullable<T> wrapped value types? The key is the System.Nullable static class.  This class is a companion class to the System.Nullable<T> class and allows you to use a few helper methods for Nullable<T> wrapped types, including a static Compare<T>() method of the. What’s so big about the static Compare<T>() method?  It implements an IComparer compatible comparison on Nullable<T> types.  Why do we care?  Well, if you look at the MSDN description for how IComparer works, you’ll read: Comparing null with any type is allowed and does not generate an exception when using IComparable. When sorting, null is considered to be less than any other object. This is what we probably want!  We want null to be less than everything!  So now we can change our logic to use the Nullable.Compare<T>() static method: 1: int? x = null; 2: int? y = 100; 3:  4: if (Nullable.Compare(x, y) < 0) 5: { 6: // Yes! x is null, y is not, so x is less than y according to Compare(). 7: Console.WriteLine("x < y"); 8: } 9: else if (Nullable.Compare(x, y) > 0) 10: { 11: Console.WriteLine("x > y"); 12: } 13: else 14: { 15: Console.WriteLine("x == y"); 16: } Summary So, when doing math comparisons between two numeric values where one of them may be a null Nullable<T>, consider using the System.Nullable.Compare<T>() method instead of the comparison operators.  It will treat null less than any value, and will avoid logic consistency problems when relying on < returning false to indicate >= is true and so on. Tweet   Technorati Tags: C#,C-Sharp,.NET,Little Wonders,Little Pitfalls,Nulalble

  Read the article

• Persistent static routes fail on MacOS 10.6.5 startup!

  - by verbalicious

  I'm unable to get static routes to persist a reboot on Mac OS 10.6.5. I've tried all of the methods prescribed in Google search results, and previous posts on this site. I've tried manually creating a launchd daemon, and used RouteSplit's launchd daemon to no avail. It's clear that the interface is not ready when these methods attempt to apply the route. This workstation in question is getting its IP from DHCP and probably hasn't gotten its DHCP lease when the command runs. We're able to apply the route by hand when logged in, but not through startup methods. Is there another way to apply this route by sneaking the command into something later, but before the login window appears to the user? Here is some relevant log info from system.log. You can see the "route: writing to routing socket: Network is unreachable" errors where my launchd script fires off. I've tried adding extra "sleep" and "ipconfig waitall" statements later in the script but this doesn't fly. Dec 15 19:30:41 localhost com.apple.launchd[1]: *** launchd[1] has started up. *** Dec 15 19:30:45 localhost mDNSResponder[18]: mDNSResponder mDNSResponder-258.13 (Oct 8 2010 17:10:30) starting Dec 15 19:30:47 localhost configd[15]: bootp_session_transmit: bpf_write(en1) failed: Network is down (50) Dec 15 19:30:47 localhost configd[15]: DHCP en1: INIT transmit failed Dec 15 19:30:47 localhost configd[15]: network configuration changed. Dec 15 19:30:47 Administrators-MacBook-Pro configd[15]: setting hostname to "Administrators-MacBook-Pro.local" Dec 15 19:30:47 Administrators-MacBook-Pro blued[16]: Apple Bluetooth daemon started Dec 15 19:30:52 Administrators-MacBook-Pro syslog[67]: routes.sh: Starting RouteSplit Dec 15 19:30:53 Administrators-MacBook-Pro com.apple.usbmuxd[41]: usbmuxd-207 built for iTunesTenOne on Oct 19 2010 at 13:50:35, running 64 bit Dec 15 19:30:54 Administrators-MacBook-Pro /System/Library/CoreServices/loginwindow.app/Contents/MacOS/loginwindow[50]: Login Window Application Started Dec 15 19:30:55 Administrators-MacBook-Pro bootlog[61]: BOOT_TIME: 1292459441 0 Dec 15 19:30:55 Administrators-MacBook-Pro syslog[86]: routes.sh: static route 192.168.0.0/23 192.168.2.2 Dec 15 19:30:55 Administrators-MacBook-Pro net.routes.static[65]: route: writing to routing socket: Network is unreachable Dec 15 19:30:55 Administrators-MacBook-Pro net.routes.static[65]: add net 192.168.0.0: gateway 192.168.2.2: Network is unreachable Dec 15 19:30:57 Administrators-MacBook-Pro org.apache.httpd[38]: httpd: Could not reliably determine the server's fully qualified domain name, using Administrators-MacBook-Pro.local for ServerName Dec 15 19:30:58 Administrators-MacBook-Pro loginwindow[50]: Login Window Started Security Agent Dec 15 19:30:58 Administrators-MacBook-Pro WindowServer[89]: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged. Dec 15 19:30:58 Administrators-MacBook-Pro com.apple.WindowServer[89]: Wed Dec 15 19:30:58 Administrators-MacBook-Pro.local WindowServer[89] <Error>: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged. Dec 15 19:31:18 Administrators-MacBook-Pro configd[15]: network configuration changed. Dec 15 19:31:19 administrators-macbook-pro configd[15]: setting hostname to "administrators-macbook-pro.local" Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[121]: /usr/libexec/ntpd-wrapper: scutil key State:/Network/Global/DNS not present after 30 seconds Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[124]: sntp options: a=2 v=1 e=0.100 E=5.000 P=2147483647.000 Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[124]: d=15 c=5 x=0 op=1 l=/var/run/sntp.pid f= time.apple.com Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[124]: sntp: getaddrinfo(hostname, ntp) failed with nodename nor servname provided, or not known Dec 15 19:31:27 administrators-macbook-pro configd[15]: network configuration changed. Dec 15 19:31:27 Administrators-MacBook-Pro configd[15]: setting hostname to "Administrators-MacBook-Pro.local" Dec 15 19:31:27 Administrators-MacBook-Pro ntpd[37]: Cannot find existing interface for address 17.151.16.20 Dec 15 19:31:27 Administrators-MacBook-Pro ntpd_initres[125]: ntpd indicates no data available! Dec 15 19:31:31 Administrators-MacBook-Pro sshd[128]: USER_PROCESS: 133 ttys000 Dec 15 19:31:37 Administrators-MacBook-Pro sudo[138]: administrator : TTY=ttys000 ; PWD=/Users/administrator ; USER=root ; COMMAND=/usr/bin/less /var/log/system.log ``You can see the following line in /var/log/kernel.log that shows the en0 interface coming up: Dec 15 19:30:51 Administrators-MacBook-Pro kernel[0]: Ethernet [AppleBCM5701Ethernet]: Link up on en0, 1-Gigabit, Full-duplex, No flow-control, Debug [796d,0f01,0de1,0300,c1e1,3800]

  Read the article

• Persistent static routes fail on MacOS 10.6.5 startup!

  - by verbalicious

  I'm unable to get static routes to persist a reboot on Mac OS 10.6.5. I've tried all of the methods prescribed in Google search results, and previous posts on this site. I've tried manually creating a launchd daemon, and used RouteSplit's launchd daemon to no avail. It's clear that the interface is not ready when these methods attempt to apply the route. This workstation in question is getting its IP from DHCP and probably hasn't gotten its DHCP lease when the command runs. We're able to apply the route by hand when logged in, but not through startup methods. Is there another way to apply this route by sneaking the command into something later, but before the login window appears to the user? Here is some relevant log info from system.log. You can see the "route: writing to routing socket: Network is unreachable" errors where my launchd script fires off. I've tried adding extra "sleep" and "ipconfig waitall" statements later in the script but this doesn't fly. Dec 15 19:30:41 localhost com.apple.launchd[1]: *** launchd[1] has started up. *** Dec 15 19:30:45 localhost mDNSResponder[18]: mDNSResponder mDNSResponder-258.13 (Oct 8 2010 17:10:30) starting Dec 15 19:30:47 localhost configd[15]: bootp_session_transmit: bpf_write(en1) failed: Network is down (50) Dec 15 19:30:47 localhost configd[15]: DHCP en1: INIT transmit failed Dec 15 19:30:47 localhost configd[15]: network configuration changed. Dec 15 19:30:47 Administrators-MacBook-Pro configd[15]: setting hostname to "Administrators-MacBook-Pro.local" Dec 15 19:30:47 Administrators-MacBook-Pro blued[16]: Apple Bluetooth daemon started Dec 15 19:30:52 Administrators-MacBook-Pro syslog[67]: routes.sh: Starting RouteSplit Dec 15 19:30:53 Administrators-MacBook-Pro com.apple.usbmuxd[41]: usbmuxd-207 built for iTunesTenOne on Oct 19 2010 at 13:50:35, running 64 bit Dec 15 19:30:54 Administrators-MacBook-Pro /System/Library/CoreServices/loginwindow.app/Contents/MacOS/loginwindow[50]: Login Window Application Started Dec 15 19:30:55 Administrators-MacBook-Pro bootlog[61]: BOOT_TIME: 1292459441 0 Dec 15 19:30:55 Administrators-MacBook-Pro syslog[86]: routes.sh: static route 192.168.0.0/23 192.168.2.2 Dec 15 19:30:55 Administrators-MacBook-Pro net.routes.static[65]: route: writing to routing socket: Network is unreachable Dec 15 19:30:55 Administrators-MacBook-Pro net.routes.static[65]: add net 192.168.0.0: gateway 192.168.2.2: Network is unreachable Dec 15 19:30:57 Administrators-MacBook-Pro org.apache.httpd[38]: httpd: Could not reliably determine the server's fully qualified domain name, using Administrators-MacBook-Pro.local for ServerName Dec 15 19:30:58 Administrators-MacBook-Pro loginwindow[50]: Login Window Started Security Agent Dec 15 19:30:58 Administrators-MacBook-Pro WindowServer[89]: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged. Dec 15 19:30:58 Administrators-MacBook-Pro com.apple.WindowServer[89]: Wed Dec 15 19:30:58 Administrators-MacBook-Pro.local WindowServer[89] <Error>: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged. Dec 15 19:31:18 Administrators-MacBook-Pro configd[15]: network configuration changed. Dec 15 19:31:19 administrators-macbook-pro configd[15]: setting hostname to "administrators-macbook-pro.local" Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[121]: /usr/libexec/ntpd-wrapper: scutil key State:/Network/Global/DNS not present after 30 seconds Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[124]: sntp options: a=2 v=1 e=0.100 E=5.000 P=2147483647.000 Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[124]: d=15 c=5 x=0 op=1 l=/var/run/sntp.pid f= time.apple.com Dec 15 19:31:25 administrators-macbook-pro _mdnsresponder[124]: sntp: getaddrinfo(hostname, ntp) failed with nodename nor servname provided, or not known Dec 15 19:31:27 administrators-macbook-pro configd[15]: network configuration changed. Dec 15 19:31:27 Administrators-MacBook-Pro configd[15]: setting hostname to "Administrators-MacBook-Pro.local" Dec 15 19:31:27 Administrators-MacBook-Pro ntpd[37]: Cannot find existing interface for address 17.151.16.20 Dec 15 19:31:27 Administrators-MacBook-Pro ntpd_initres[125]: ntpd indicates no data available! Dec 15 19:31:31 Administrators-MacBook-Pro sshd[128]: USER_PROCESS: 133 ttys000 Dec 15 19:31:37 Administrators-MacBook-Pro sudo[138]: administrator : TTY=ttys000 ; PWD=/Users/administrator ; USER=root ; COMMAND=/usr/bin/less /var/log/system.log ``You can see the following line in /var/log/kernel.log that shows the en0 interface coming up: Dec 15 19:30:51 Administrators-MacBook-Pro kernel[0]: Ethernet [AppleBCM5701Ethernet]: Link up on en0, 1-Gigabit, Full-duplex, No flow-control, Debug [796d,0f01,0de1,0300,c1e1,3800]

  Read the article

< Previous Page | 20 21 22 23 24 25 26 27 28 29 30 31  | Next Page >