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• Dojo and Separate JavaScript File

  - by Bunch

  For a project I needed to use the ArcGIS API for some mapping. To use this you need to use Dojo but in this case all it really comes down to is adding some require lines and a addOnLoad on your web page. At first everything was working great, the maps rendered and the various layers would populate as needed. Once it was working I started moving the various javascript functions into their own files to keep everything nice and neat. Then the problems started, mainly the map would not show up any more. So that was a pretty big problem. Luckily the fix was pretty simple, just move the dojo.addOnLoad line into it’s own script tag. If I had the dojo.addOnLoad in the same script block as the various require lines it would not work as expected. Works: <script type="text/javascript" language="javascript" src="javascript/test.js" />     <script type="text/javascript">       dojo.require("esri.map");       dojo.require("esri.tasks.locator");       dojo.require("esri.tasks.query");       dojo.require("esri.tasks.geometry");  </script>  <script type="text/javascript">      dojo.addOnLoad(init);  </script> Does not work: <script type="text/javascript" language="javascript" src="javascript/test.js" /> <script type="text/javascript">       dojo.require("esri.map");       dojo.require("esri.tasks.locator");       dojo.require("esri.tasks.query");       dojo.require("esri.tasks.geometry");       dojo.addOnLoad(init); </script> Technorati Tags: JavaScript,Dojo

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• The Enterprise Side of JavaFX: Part Two

  - by Janice J. Heiss

  A new article, part of a three-part series, now up on the front page of otn/java, by Java Champion Adam Bien, titled “The Enterprise Side of JavaFX,” shows developers how to implement the LightView UI dashboard with JavaFX 2. Bien explains that “the RESTful back end of the LightView application comes with a rudimentary HTML page that is used to start/stop the monitoring service, set the snapshot interval, and activate/deactivate the GlassFish monitoring capabilities.”He explains that “the configuration view implemented in the org.lightview.view.Browser component is needed only to start or stop the monitoring process or set the monitoring interval.”Bien concludes his article with a general summary of the principles applied:“JavaFX encourages encapsulation without forcing you to build models for each visual component. With the availability of bindable properties, the boundary between the view and the model can be reduced to an expressive set of bindable properties. Wrapping JavaFX components with ordinary Java classes further reduces the complexity. Instead of dealing with low-level JavaFX mechanics all the time, you can build simple components and break down the complexity of the presentation logic into understandable pieces. CSS skinning further helps with the separation of the code that is needed for the implementation of the presentation logic and the visual appearance of the application on the screen. You can adjust significant portions of an application's look and feel directly in CSS files without touching the actual source code.”Check out the article here.

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• DIY Halloween Decoration Uses Simple Silohuettes

  - by Jason Fitzpatrick

  While many of the Halloween decorating tricks we’ve shared over the years involve lots of wire, LEDs, and electronic guts, this one is thoroughly analog (and easy to put together). A simple set of silhouettes can cheaply and quickly transform the front of your house. Courtesy of Matt over at GeekDad, the transformation is easy to pull off. He explains: It’s really just about as simple as you could hope for. The materials needed are: black posterboard or black-painted cardboard; colored cellophane or tissue paper; and tape. The only tools needed are: measuring tape; some sort of drawing implement — chalk works really well; and scissors and/or X-Acto knife. And while you need some drawing talent, the scale is big enough and the need for precision little enough that you don’t need that much. For a more thorough rundown of the steps hit up the link below or hit up Google Images to find some monster silhouette inspiration. Window Monsters [Geek Dad] How Hackers Can Disguise Malicious Programs With Fake File Extensions Can Dust Actually Damage My Computer? What To Do If You Get a Virus on Your Computer

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• Accessing ADF Faces components that are read-only from JavaScript

  - by Frank Nimphius

  Almost as a note to myself and to justify the time I spent on analyzing aproblem, a quick note on what to watch out for when working trying to access read-only ADF Faces components from JavaScript.  Those who tried JavaScript in ADF Faces probably know that you need to ensure the ADF Faces component  is represented by a JavaScript object on the client. You do this either implicitly by adding an af:clientListener component (in case you want to listen for a component event) or explicitly by setting the ADF Faces component clientComponent property to true. For the use case I looked at in JDeveloper 11g R1 (11.1.1.7) I needed to make an output text component clickable to call a JavaScript function in response. Though I added the af:clientComponent tag to the component I recognized that it also needed the clientComponent property set to true. Though I remember this as not being required in 11.1.1.6, I like the new behavior as it helps preventing read-only components from firing client side events unless you tell it to do so by setting the clientComponent property to true. Note: As the time of writing, JDeveloper 11.1.1.7 is not publicly available and I put the note in this blog as a reminder in case you ever hit a similar challenge so you know what to do.

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• 64kb limit on the size of MSMQ Multicast Messages

  - by John Breakwell

  When Windows 2003 came out, Microsoft introduced the ability to broadcast messages to any machines that were listening back. All you had to do was send out a message on a particular port and IP address and any client that had set up a Multicast queue with matching port and IP address would get a copy. Since its introduction, there have been a couple of security vulnerabilities that needed to be removed: Microsoft Security Bulletin MS06-052 Vulnerability in Pragmatic General Multicast (PGM) Could Allow Remote Code Execution (919007) Microsoft Security Bulletin MS08-036 Vulnerabilities in Pragmatic General Multicast (PGM) could allow denial of service (950762) The second of these, MS08-036, was resolved through an undocumented change in functionality. Basically, a limit of 64kb was put on the maximum size of a message that could be broadcast using the Multicast method. Obviously this has caused a few problems for any existing MSMQ Multicast applications that expected to be able to send larger messages. A hotfix has been developed to resolve this problem. 961605 FIX: Multicast messages larger than 64 kilobytes (KB) are not delivered as expected by using Message Queuing 3.0 after security update MS08-036 is installed A registry change is required: Open the registry with Regedit Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\RMCAST\Parameters\ Create a DWord called MaxpacketSize Set the value to the desired number of bytes. You can set it to a value between zero and 4MB. If you specify anything above 4MB, it will default to 64K. A reboot is needed after adding this value.

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• People != Resources

  - by eddraper

  Ken Tabor’s blog post “They Are not Resources – We Are People” struck a chord with me.  I distinctly remember hearing the term “resources” within the context of “people” for the first time back in the late 90’s.  I was in a meeting at Compaq and a manager had been faced with some new scope for an IT project he was managing.  His response was that he needed more “resources” in order to get the job done.  As I knew the timeline for the project was fixed and the process for acquiring additional funding would almost certainly extend beyond his expected delivery date, I wondered what he meant.  After the meeting, I asked him what he meant… his response was that he needed some more “bodies” to get the job done.  For a minute, my mind whirred… why is it so difficult to simply say “people?”  This particular manager was neither a bad person nor a bad manager… quite the contrary.  I respected him quite a bit and still do.  Over time, I began to notice that he was what could be termed an “early adopter” of many “Business speak” terms – such as “sooner rather than later,” “thrown a curve,” “boil the ocean” etcetera.  Over time, I’ve discovered that much of this lexicon can actually be useful, though cliché and overused.  For example, “Boil the ocean” does serve a useful purpose in distilling a lot of verbiage and meaning into three simple words that paint a clear mental picture.  The term “resources” would serve a similar purpose if it were applied to the concept of time, funding, or people.  The problem is that this never happened.  “Resources”, “bodies”, “ICs” (individual contributors)… this is what “people” have become in the IT business world.  Why?  We’re talking about simple word choices here.  Why have human beings been deliberately dehumanized and abstracted in this manner? What useful purpose does it serve other than to demean and denigrate?

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• When is it ever ok to write your own development tools? (editor into IDE)

  - by mario

  So I'm foremost using a text editor for coding. It's a very bare bones editor; provides mostly just syntax highlighting. But on rare occasions I also need to debug something. And that's when I have to resort to an IDE (mostly Netbeans, but got fiddly Eclipse/Aptana working as second fallback). For general use however IDEs feel not workable to me. It's a visual thing, being used to console UIs etc. And switching back and forth between a text editor and an IDE is slightly cumbersome too. That's why I'm considering extending the editor, not really into a full-fledged IDE - but at the very least integrate a debug feature. Since I'm working on PHP, it seems not that much effort. The DBGp allows to externalize a debug handler from the editor, so it's just minor integration work and figuring out how to shoehorn a breakpoint feature into the editor (joe btw). And while I've also got time to do that, I'm wondering if this is really worthwhile. In this case it's not a needed development tool. It's just for convenience. And the cause for doing it is basically just not liking the existing solution. While over time I might extend and adapt this debugger thing, it initially will be as circumstantial as Eclipse. It inevitably starts out as poor development tool. Furthermore there is likely not much reuse. (Okay, this is not an important point. Most such software exists sans much of a use case. And also obviously, similar extensions already exist for emacs and vim, so it cannot be completely pointless.) But what's a general guideline on attempting to conoct custom development tools, particularily if they are not really needed but satisfy personal preferences? (Usability enhancement not certain.)

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• Error -12 hibernation image. Not enough free memory (sometimes)

  - by user99306

  I am having a problem with hibernation in Ubuntu 12.10, it had worked fine in 12.04. When I try and hibernate it sometimes appears to hibernate throws up an error and returns me to the desktop. The error I get is this: PM: Creating hibernation image: PM: Need to copy 375021 pages PM: Normal pages needed: 117957 + 1024, available pages: 110205 PM: Not enough free memory PM: Error -12 creating hibernation image Now I understand what the error means, but it doesn't make sense. My swap file is 5GB and is seldom ever used as I have 4GB of RAM. I know it is recommended to have 1.5 times more swap than RAM etc, but space doesn't seem to be the problem, despite the error. For example, I rarely use more than about 25%-30% of my RAM, yet still have the problem above. Moreover on a fresh boot and login, with no programs open and using only about 12% of RAM, I can get the above error - yet at other times I can hibernate whilst using 25% of my RAM. Also if I keep trying to hibernate, it eventually does after throwing up the above error four or five times. A successful hibernation looks like this: PM: Creating hibernation image: PM: Need to copy 295511 pages PM: Normal pages needed: 95534 + 1024, available pages: 132627 Is there some setting that I need to tweak or something I need to do before hibernating to avoid this problem? I guess the question could be better interpreted as: Is there some way of safely flushing the buffers and the cache before hibernation? Other than attempting to hibernate several times until it is successful! Thanks in advance.

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• Example: Cross Cutting Concerns of an Application

  A little while ago I was given an opportunity to design and implement a new system that sent data via an HTTP Post method and then processed the results that were returned so that they could be inserted in to a database. My system had eight core concerns that it needed to fulfill. Eight Core Concerns Database Access Data Entities Worker Result Processing Process Flow Manager Email/Notification Error Handling Logging Of these eight, five were actually cross cutting concerns. 5 Cross Cutting Concerns Database Access Data Entities Email/Notification Error Handling Logging These five cross cutting concerns were determined after I created an aspect oriented model to help identity the system components that could be factored out into separate components.  These separated components would then be included in the system so that they could be used by various other components.  These five components allow all of the other components to access the database, store data, send notifications, handle errors, and log all system events.  Thus, these components are used to share unique aspects to the system via their implementation. The use of Aspect oriented architecture greatly helped me define what components I needed to create and what each of those components could do.  It also showed how all of the other aspects depended on each other so that each component did not have to re-implement code that was already created in the existing system.

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• Impact of Service Oriented Architecture (SOA) on Business and IT Operations

  The impact of Service Oriented Architecture (SOA) on business and IT operations varies from company to company. I think more and more companies are starting to view SOA as just another technology that they can incorporate in an existing or new system. One of the driving factors in using SOA is the reduction in maintenance costs and decrease in the time needed to bring products to market. The reductions in costs, and reduced turnaround time can be directly converted in to increased profitability due to less expenditures that are needed in order to maintain or create new systems. My personal perspective on SOA is that it is great for what it is actually intended to do. SOA allows systems to be distributed across networks or even the world while ensuring enterprise processing consistency, data integrity and preventing code duplication. This being said a lot of preparation and work goes into properly designing and implementing an SOA especially if an enterprise wants to take full advantage of its benefits. Even though SOA has recently gotten a lot of hype about its benefits it does not a perfect fit for all situations. At the end of the day SOA is just another tool in my tool belt that I can pull from to create solutions that meet the business’s needs. Based on current industry trends SOA appears to be a very solid technology to use moving forward, especially as more and more companies shift towards cloud based computing. It is important to remember that SOA is one of many technologies that can be used in creating business solutions and I think more time will be spent in the future evaluating if SOA is the right technology for a solution once the initial hype of SOA has calmed down.

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• what other bash variables are available during execution such as $USER that can assist on my script?

  - by semi-newbie

  This is related to question 19245, in that one of the responders answered the question in an awesome way, and very VERY clear to any newbie. Now here is a question that i can't seem to figure. i wrote a script for starting the vmware firefox plugin (don't worry. i gave that up and now run vBox VERY happily. i left vmware for my servers :) ) I needed to start the plugin as sudo, but i also needed to pass an argument (password) to it, that happen to be the same. So, if my password was Hello123, the command would be: sudo ./myscript.sh hi other Hello123 running from command line, the script would ask for my sudo password and then run. i wanted to capture THAT password and pass it as well. i also wanted to run graphically, so i tried gksudo, and there is an option -p that returns the password for variable assignment. well, that was a nightmare, because i would still get prompted for the original sudo: see below Find UserName vUser=$USER Find password (and hopefully enable sudo) vP=gksudo -p -D somedescriptiontext echo Execute command gksudo ./myscript.sh hi $vUser $vP and i still get prompted twice. so my question is tri-fold: is there a variable i can use for the password, just like there is one for user, $USER? is there a different way i should be assigning the value resulting of the command i have in $vP? i am wondering if executing the way i have it, does it in an uninitiated session and not the current one, since i am getting some addtl warning type errors on some variables blah blah i tried using Zenity to just capture the text, but then of course, i couldn't pass that value to sudo, so i could only use as a parameter, which puts me back in 2 prompts. Thanksssssssssss!

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• TechEd 2012: Fast SQL Server

  - by Tim Murphy

  While I spend a certain amount of my time creating databases (coding around SQL Server and setup a server when I have to) it isn’t my bread and butter.  Since I have run into a number of time that SQL Server needed to be tuned I figured I would step out of my comfort zone and see what I can learn. Brent Ozar packed a mountain of information into his session on making SQL Server faster.  I’m not sure how he found time to hit all of his points since he was allowing the audience abuse him on Twitter instead of asking questions, but he managed it.  I also questioned his sanity since he appeared to be using a fruit laptop. He had my attention though when he stated that he had given up on telling people to not use “select *”. He posited that it could be fixed with hardware by caching the data in memory.  He continued by cautioning that having too many indexes could defeat this approach.  His logic was sound if not always practical, but it was a good place to start when determining the trade-offs you need to balance.  He was moving pretty fast, but I believe he was prescribing this solution predominately for OLTP database prior to moving on to data warehouse solutions. Much of the advice he gave for data warehouses is contained in the Microsoft Fast Track guidance so I won’t rehash it here.  To summarize the solution seems to be the proper balance memory, disk access speed and the speed of the pipes that get the data from storage to the CPU.  It appears to be sound guidance and the session gave enough information that going forward we should be able to find the details needed easily.  Just what the doctor ordered. del.icio.us Tags: SQL Server,TechEd,TechEd 2012,Database,Performance Tuning

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• Project Showcase: SaaS Web Apps Hits a Home Run with New SCMS Database

  - by Webgui

  We love seeing projects from start to finish, and we’re happy to share the latest example with you. Who: SaaS Web Apps – they use Software as a Service to create web applications that look and feel like desktop applications. What: SaaS Web Apps needed to build a Sports Contract Management System (SCMS) for one of its customers, Premier Stinson Sports. Why: The SCMS database is used for collecting, analyzing and recording college coach and athletic directors’ employment and contract data. The Challenge: Premier Stinson Sports works with a number of partners, each with its own needs and unique requirements. For example, USA Today uses the system to provide cutting edge news analysis while The National Sports Law Institute of Marquette University Law School uses it to for the latest sports contract data and student analysis. In addition, the system needed to be secure due to the sensitivity of the data; it was essential that the user security and permissions be easily configurable. As always, performance was a key factor, especially with the intense reporting and analytical capabilities for this project. Because of this, most of the processing had to be done on a dedicated server but the project called for the richness and responsiveness of a desktop application. The Solution: To execute the project, SaaS Web Apps used APS.Net-based Visual WebGui from Gizmox, combined with SQL Server 2008 and SQL Reporting Services. This combination resulted in a quick deployment for SaaS Web Apps’ customers. The Result: The completed project gave each partner the scalability and availability of a web application with the performance and security of a desktop application. As an example, USA Today pulls data from this database to give readers the latest sports stats – Salary analysis of 2010 Football Bowl Subdivision Coaches. And here’s a screenshot of the database itself. Great work, SaaS Web Apps!

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• RequireJS: JavaScript for the Enterprise

  - by Geertjan

  I made a small introduction to RequireJS via some of the many cool new RequireJS features in NetBeans IDE. I believe RequireJS, and the modularity and encapsulation and loading solutions that it brings, provides the tools needed for creating large JavaScript applications, i.e., enterprise JavaScript applications. &amp;amp;lt;span id=&amp;amp;quot;XinhaEditingPostion&amp;amp;quot;&amp;amp;gt;&amp;amp;lt;/span&amp;amp;gt; (Sorry for the wobbly sound in the above.) An interesting comment by my colleague John Brock on the above: One other advantage that RequireJS brings, is called lazy loading of resources. In your first example, everyone one of those .js files is loaded when the first file is loaded in the browser. By using the require() call in your modules, your application will only load the javascript modules when they are actually needed. It makes for faster startup in large applications. You could show this by showing the libraries that are loaded in the Network Monitor window. So I did as suggested: Click the screenshot to enlarge it and notice how the Network Monitor is helpful in the context of RequireJS troubleshooting.

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• Convert collections of enums to collection of strings and vice versa

  - by Michael Freidgeim

  Recently I needed to convert collections of  strings, that represent enum names, to collection of enums, and opposite,  to convert collections of   enums  to collection of  strings. I didn’t find standard LINQ extensions.However, in our big collection of helper extensions I found what I needed - just with different names: /// <summary> /// Safe conversion, ignore any unexpected strings/// Consider to name as Convert extension /// </summary> /// <typeparam name="EnumType"></typeparam> /// <param name="stringsList"></param> /// <returns></returns> public static List<EnumType> StringsListAsEnumList<EnumType>(this List<string> stringsList) where EnumType : struct, IComparable, IConvertible, IFormattable     { List<EnumType> enumsList = new List<EnumType>(); foreach (string sProvider in stringsList)     {     EnumType provider;     if (EnumHelper.TryParse<EnumType>(sProvider, out provider))     {     enumsList.Add(provider);     }     }     return enumsList;     }/// <summary> /// Convert each element of collection to string /// </summary> /// <typeparam name="T"></typeparam> /// <param name="objects"></param> /// <returns></returns> public static IEnumerable<string> ToStrings<T>(this IEnumerable<T> objects) {//from http://www.c-sharpcorner.com/Blogs/997/using-linq-to-convert-an-array-from-one-type-to-another.aspx return objects.Select(en => en.ToString()); }

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• Reliance on Outlook (been a looong time, I know)

  - by AndyScott

  Do you feel that your development group too reliant on Outlook? Have you reached a point that you have to search your email for pertinent information when asked? What are you using? I realized things had gotten out of hand a couple weeks ago over a weekend. I was at my in-laws house (in the country, no PC/laptop, no internet connection; and I get an email on my phone that I needed to reply to, but I couldn't send without deleting items from my inbox/sent items/etc. Now mind you, I have rules set up to move stuff into folders, and files more than a month old are automatically moved to the PST; but generally don't manually move items to a PST until I have had a chance to 'work' the item. Please don't bother mocking my process, it's just the way I work. That being said, it was a frustrating process of 'I need all this information, what can I afford to lose'. I work on an International project (think lots of customers), and conversations in 9 or 10 different directions about 10-20 different things are not abnormal for a given day. I have found myself looking data up in Outlook because that's where it is. I think that I have reached the point now, where I don't feel that Outlook is up to the task of organizing the data that it contains.   When you have that many emails (200 or so a day), information seems to get lost at times, and I find that Outlook's search capabilities are lacking. Additionally, I find that any sort of organizational 'system' of sorting emails that can cover multiple topics is a lost cause. But at the same time, the old process of taking the information that I got from emails and moving it into another 'notes' type of program has proved to be too time consuming. Anyone out there have some better type of system? (Comments about the capacity of my brain, and it's ability to recall information not needed.)

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• How to Program AWS Spot Instances to Strategically Bid So the Auction is Never Lost Until a Competitor Beats the Maximum I'm Willing to Pay?

  - by Taal

  I believe I'm in the right section of stack exchange to ask this. If not, let me know. I only use Amazon Web Services for temporary type hosting services, so the spot instances are quite valuable to me. I would also just make an instance and start and stop it - but - that doesn't necessarily fit my bootstrapped budget sadly. Anyways, it really kills me when someone outbids me on a spot instance I have (I tend to go for the larger ones which there are fewer of available) and I get randomly kicked off. I know or at least I believe there is a way to program in something somehow to dynamically change your bidding price to beat a potential competitor's if their's is higher than yours. Now, I previously believed Amazon would just charge me for the highest price right above the next lowest competitor automatically (eliminating the need for this) - so if I bid too high, then I only pay what I would of needed to in order to win and keep the auction. Essentially, I thought my bid price was my max bid price. Apparently, according to my bills and several experiments I've done - this is not the case. They charge me for whatever I bid even when I know there is no one else around to counter bid me. I needed to clarify that, but let me get back to the main point: Let's say I'm bidding $0.50, competitor comes in and bids 0.55 cents. I get kicked off. I want to have it to where I'd set a maximum I'm willing to pay (let's say $1.00 here), and then when competitor comes in and tries to bid $.55, my bid is dynamically adjusted to beat his at $0.56 up until he breaks my $1.00 threshold. I've been reading the guides and although they are more or less straightforward, I feel like they leave a few holes in them that end up confusing me. Like, for instance, where do I input said command or when do I do it? Maybe I'm just tech illiterate and need help deciphering these guides. A good start for someone willing to answer/help me decipher this problem would be here: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/spot-as-update-bid.html

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• MVC 4 Authentication

  - by Aligned

  First: After searching for awhile to figure out what’s new/different with MVC 4 and forms authentication, this is the best article I've found on the subject: http://weblogs.asp.net/jgalloway/archive/2012/08/29/simplemembership-membership-providers-universal-providers-and-the-new-asp-net-4-5-web-forms-and-asp-net-mvc-4-templates.aspx Some quotes from the article: “The ASP.NET Web Pages team designed SimpleMembership to (wait for it) simplify the task of dealing with membership” "WSAT is built to work with ASP.NET Membership, and is not compatible with Simple Membership. There are two main options there: Use the WebSecurity and OAuthWebSecurity API to manage the users and roles Create a web admin using the above APIs Since SimpleMembership runs on top of your database, you can update your users as you would any other data - via EF or even in direct database edits (in development, of course)" “If you want to use an existing ASP.NET Membership Provider in ASP.NET MVC 4, you can't use the new AccountController. You can do a few things:” “Universal Providers do not work with Simple Membership.” ~ this post (look for Bob.at.SBS’s answer) says Universal Providers is not needed for MVC 4 to work in Azure)   I've been trying to figure out the Forms Authentication in MVC4. It's different than the past approach (aspnet_regsql). If you do file new project -> MVC 4 -> internet application, you get a really nice template with the controller and model setup for you. However, the tables are different than using aspnet_regsql and the ASP.Net Configuration tool (WSAT) wasn’t connecting to the data I had (it was creating an App_Data/aspnet.mdf file, which I didn’t see right away). Points of Note The database tables are created in the SimpleMembershipInitializer class, when you first run your app using Entity Framework 5 migration functionality. The tables created are webpages_Membership, webpages_OAuthMembership, webpages_Roles, webpages_UsersInRoles, UserProfile. Web.config settings don’t seem to be needed.   Scott Hanselman on Universal Providers was also useful if not somewhat out dated. Universal Providers and SimpleMembership are not compatible. http://www.asp.net/web-pages/tutorials/security/16-adding-security-and-membership – walk-through

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• The Interaction between Three-Tier Client/Server Model and Three-Tier Application Architecture Model

  The three-tier client/server model is a network architectural approach currently used in modern networking. This approach divides a network in to three distinct components. Three-Tier Client/Server Model Components Client Component Server Component Database Component The Client Component of the network typically represents any device on the network. A basic example of this would be computer or another network/web enabled devices that are connected to a network. Network clients request resources on the network, and are usually equipped with a user interface for the presentation of the data returned from the Server Component. This process is done through the use of various software clients, and example of this can be seen through the use of a web browser client. The web browser request information from the Server Component located on the network and then renders the results for the user to process. The Server Components of the network return data based on specific client request back to the requesting client.  Server Components also inherit the attributes of a Client Component in that they are a device on the network and that they can also request information from other Server Components. However what differentiates a Client Component from a Server Component is that a Server Component response to requests from devices on the network. An example of a Server Component can be seen in a web server. A web server listens for new requests and then interprets the request, processes the web pages, and then returns the processed data back to the web browser client so that it may render the data for the user to interpret. The Database Component of the network returns unprocessed data from databases or other resources. This component also inherits attributes from the Server Component in that it is a device on a network, it can request information from other server components and database components, and it also listens for new requests so that it can return data when needed. The three-tier client/server model is very similar to the three-tier application architecture model, and in fact the layers can be mapped to one another. Three-Tier Application Architecture Model Presentation Layer/Logic Business Layer/Logic Data Layer/Logic The Presentation Layer including its underlying logic is very similar to the Client Component of the three-tiered model. The Presentation Layer focuses on interpreting the data returned by the Business Layer as well as presents the data back to the user.  Both the Presentation Layer and the Client Component focus primarily on the user and their experience. This allows for segments of the Business Layer to be distributable and interchangeable because the Presentation Layer is not directly integrated in with Business Layer. The Presentation Layer does not care where the data comes from as long as it is in the proper format. This allows for the Presentation Layer and Business Layer to be stored on one or more different servers so that it can provide a higher availability to clients requesting data. A good example of this is a web site that uses load balancing. When a web site decides to take on the task of load balancing they must obtain a network device that sits in front of a one or machines in order to distribute the request across multiple servers. When a user comes in through the load balanced device they are redirected to a specific server based on a few factors. Common Load Balancing Factors Current Server Availability Current Server Response Time Current Server Priority The Business Layer and corresponding logic are business rules applied to data prior to it being sent to the Presentation Layer. These rules are used to manipulate the data coming from the Data Access Layer, in addition to validating any data prior to being stored in the Data Access Layer. A good example of this would be when a user is trying to create multiple accounts under one email address. The Business Layer logic can prevent duplicate accounts by enforcing a unique email for every new account before the data is even stored in the Data Access Layer. The Server Component can be directly tied to this layer in that the server typically stores and process the Business Layer before it is returned to the end-user via the Presentation Layer. In addition the Server Component can also run automated process through the Business Layer on the data in the Data Access Layer so that additional business analysis can be derived from the data that has been already collected. The Data Layer and its logic are responsible for storing information so that it can be easily retrieved. Typical in most modern applications data is stored in a database management system however data can also be in the form of files stored on a file server. In addition a database can take on one of several forms. Common Database Formats XML File Pipe Delimited File Tab Delimited File Comma Delimited File (CSV) Plain Text File Microsoft Access Microsoft SQL Server MySql Oracle Sybase The Database component of the Networking model can be directly tied to the Data Layer because this is where the Data Layer obtains the data to return back the Business Layer. The Database Component basically allows for a place on the network to store data for future use. This enables applications to save data when they can and then quickly recall the saved data as needed so that the application does not have to worry about storing the data in memory. This prevents overhead that could be created when an application must retain all data in memory. As you can see the Three-Tier Client/Server Networking Model and the Three-Tiered Application Architecture Model rely very heavily on one another to function especially if different aspects of an application are distributed across an entire network. The use of various servers and database servers are wonderful when an application has a need to distribute work across the network. Network Components and Application Layers Interaction Database components will store all data needed for the Data Access Layer to manipulate and return to the Business Layer Server Component executes the Business Layer that manipulates data so that it can be returned to the Presentation Layer Client Component hosts the Presentation Layer that  interprets the data and present it to the user

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• How to find domain registrar and DNS hosting with good DNSSEC support?

  - by rsp

  Simplified problem I want to buy a domain and make a website that is fully secured with DNSSEC. Background I've been hearing about the insecurity of DNS for years. I've watched all of the talks by Dan Kaminsky and others from DNS exploits to The future of DNS Security Panel. I knew that using DNS without security is a disaster waiting to happen. I followed the development of the DNSSEC standard. I celebrated the key signing ceremony. Everything was on the right track to finally have a secure DNS system in place. And now more than 2 years later I wanted to just do what everyone said I should do: use DNSSEC for a new domain. So I need a domain registrar and a DNS hosting service that supports DNSSEC. Surprisingly it is not that easy to even find out who does support DNSSEC. It was actually much easier to find info on DNSSEC two years ago when everyone was going to support DNSSEC Real Soon Now but now years passed and I hardly see any progress done. I just hope that I was just looking in the wrong places and someone here will explain all of the doubts. I hope that other people who want to have a secure website will also find this question useful. What is needed registrar and DNS servers with full DNSSEC support for .com domains What is not needed IPv6 support Web hosting anything more What I found out so far Go Daddy offers Premium DNS service for additional $36 per year that lets you "Secure up to 5 domains with DNSSEC". easyDNS has DNSSEC available in Beta across all service levels (you need to enable the "beta" flag in configuration) but it doesn't seem to be production ready and judging from the lack of updates it isn't a feature of highest priority (the last update from March 2011 on the easyDNS blog). Name.com - according to The Register (US domain registrar does IPv6, DNSSEC) it has DNSSEC support since 2010 but right now (October 2012) I couldn't find anything related to DNSSEC on their website. Dynadot that is very often recommended doesn't support DNSSEC Namecheap that is also often recommended doesn't support DNSSEC. The support answer from 2011 suggested that it was being added but in 2012 still no ETA is given to customers. DynDNS was supposed to support DNSSEC, I found a link explaining DNSSEC support but it gives 404 Not Found page and offers a search box - when searching for DNSSEC I get "No results were found for your query." GKG was recommended online for DNSSEC support but it's hard to find any information on the level of DNSSEC support - there is a brief explanation on what is DNSSEC and how to sign Delegation Signer records in their FAQ but no information about the level of actual support can be found. Ask Slashdot: Which Registrars Support DNSSEC? from July 2011 - Answers list Go Daddy, DynDNS, GKG, Name.com as registrars that support DNSSEC but: see above. Related questions How to find web hosting that meets my requirements? What is needed to add DNSSEC to my site? DNS hosting better managed by Domain provider or Hosting provider? Registrar with good security, DNS hosting, and DNSSEC and IPv6 resolvers? In no. 1 no one is ever mentioning DNS at all. In no. 2 answers only mention the .se TLD, there are very few answers and they seem very outdated. In no. 3 one answer says "On projects that demand higher security, I might look for a web host that supports DNSSEC" but no more information is provided. The only relevant answers are in no. 4 where easyDNS is recommended by someone who has never used them personally. Meanwhile, as of October 2012, the support of DNSSEC is described as "in beta" on the easyDNS feature list. Another one recommends SiteGround but searching their site for DNSSEC returns no results. Other answers recommend web hosting providers that don't meet the requirement of DNSSEC support. Also the question mentioned above lists 9 very specific requirements other than only DNSSEC (like eg. HTTP-only login cookies, two-factor authentications, no DNS record limits, DNS statistics of queries/day, audit trails etc.) which might have excluded many possible recommendations if one is only interested in DNSSEC support. Conclusions I thought that by the end of 2012 the support of DNSSEC among domain registrars and DNS providers would be nearly universal. I am shocked that the support seems virtually nonexistent. Is this a result of some serious problems with the DNSSEC adoption? Or is it just not a hot topic and no one bothers anymore? According to the DNSSEC Scoreboard roughly about 0.1% of .com domains support DNSSEC. Could that be caused by the lack of DNSSEC support among registrars and DNS providers, is the information too hard to find or maybe no one cares? There is even no "dnssec" tag here. Questions The information is surprisingly hard to find. That is why I am asking for first-hand experience and personal recommendations. Has anyone here actually set up a website with DNSSEC, from the domain registration to the configuration of DNS servers? Can anyone recommend any of the registrars mentioned above? Can anyone recommend any registrar not mentioned above?

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• Adding a Network Loopback Adapter to Windows 8

  - by Greg Low

  I have to say that I continue to be frustrated with finding out how to do things in Windows 8. Here's another one and it's recorded so it might help someone else. I've also documented what I tried so that if anyone from the product group ever reads this, they'll understand how I searched for it and might try to make it easier.I wanted to add a network loopback adapter, to have a fixed IP address to work with when using an "internal" network with Hyper-V. (The fact that I even need to do this is also painful. I don't know why Hyper-V can't make it easy to work with host system folders, etc. as easily as I can with VirtualPC, VirtualBox, etc. but that's a topic for another day).In the end, what I needed was a known IP address on the same network that my guest OS was using, via the internal network (which allows connectivity from the host OS to/from guest OS's).I started by looking in the network adapters areas but there is no "add" functionality there. Realising that this was likely to be another unexpected challenge, I resorted to searching for info on doing this. I found KB article 2777200 entitled "Installing the Microsoft Loopback Adapter in Windows 8 and Windows Server 2012". Aha, I thought that's what I'd need. It describes the symptom as "You are trying to install the Microsoft Loopback Adapter, but are unable to find it." and that certainly sounded like me. There's a certain irony in documenting that something's hard to find instead of making it easier to find. Anyway, you'd hope that in that article, they'd then provide a step by step example of how to do it, but what they supply is this: The Microsoft Loopback Adapter was renamed in Windows 8 and Windows Server 2012. The new name is "Microsoft KM-TEST Loopback Adapter". When using the Add Hardware Wizard to manually add a network adapter, choose Manufacturer "Microsoft" and choose network adapter "Microsoft KM-TEST Loopback Adapter".The trick with this of course is finding the "Add Hardware Wizard". In Control Panel -> Hardware and Sound, there are options to "Add a device" and for "Device Manager". I tried the "Add a device" wizard (seemed logical to me) but after that wizard tries it's best, it just tells you that there isn't any hardware that it thinks it needs to install. It offers a link for when you can't find what you're looking for, but that leads to a generic help page that tells you how to do things like turning on your printer.In Device Manager, I checked the options in the program menus, and nothing useful was present. I even tried right-clicking "Network adapters", hoping that would lead to an option to add one, also to no avail.So back to the search engine I went, to try to find out where the "Add Hardware Wizard" is. Turns out I was in the right place in Device Manager, but I needed to right-click the computer's name, and choose "Add Legacy Hardware". No doubt that hasn't changed location lately but it's a while since I needed to add one so I'd forgotten. Regardless, I'm left wondering why it couldn't be in the menu as well.Anyway, for a step by step list, you need to do the following:1. From Control Panel, select "Device Manager" under the "Devices and Printers" section of the "Hardware and Sound" tab.2. Right-click the name of the computer at the top of the tree, and choose "Add Legacy Hardware".3. In the "Welcome to the Add Hardware Wizard" window, click Next.4. In the "The wizard can help you install other hardware" window, choose "Install the hardware that I manually select from a list" option and click Next.5. In the "The wizard did not find any new hardware on your computer" window, click Next.6. In the "From the list below, select the type of hardware you are installing" window, select "Network Adapters" from the list, and click Next.7. In the "Select Network Adapter" window, from the Manufacturer list, choose Microsoft, then in the Network Adapter window, choose "Microsoft KM-TEST Loopback Adapter", then click Next.8. In the "The wizard is ready to install your hardware" window, click Next.9. In the "Completing the Add Hardware Wizard" window, click Finish.Then you need to continue to set the IP address, etc.10. Back in Control Panel, select the "Network and Internet" tab, click "View Network Status and Tasks".11. In the "View your basic network information and set up connections" window, click "Change adapter settings".12. Right-click the new adapter that has been added (find it in the list by checking the device name of "Microsoft KM-TEST Loopback Adapter"), and click Properties.   

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• Need help with testdisk output

  - by dan

  I had (note the past tense) an ubuntu 12.04 system with separate partitions for the base and /home directories. It started acting wonky, so I decided to do a reinstall with 12.10, intending just to do a reinstall to the base partition. After several seconds, I realize that the installer was repartitioning the drive and reinstalling, so I pulled the power cord. I'm now trying to recover as much as I can with testdisk, but it seems that testdisk is finding 100 unique partitions when I run it - they mostly tend to be HFS+ or solaris /home (which I think is just an ext4; I've never had solaris on the machine). I've pasted an abbreviated version of the testdisk output below (first ~100 lines, and then ~100 lines from the middle of the output). Is there a way to combine or recreate the partitions and then data recovery, or some other way maximize what I can recover (ideally as much of the file system as possible)? I really only care about what was in the /home directory - I'd rather not use photorec since I don't have another 2 TB HD lying around to recover to. Thanks, Dan Mon Dec 10 06:03:00 2012 Command line: TestDisk TestDisk 6.13, Data Recovery Utility, November 2011 Christophe GRENIER <[email protected]> http://www.cgsecurity.org OS: Linux, kernel 3.2.34-std312-amd64 (#2 SMP Sat Nov 17 08:06:32 UTC 2012) x86_64 Compiler: GCC 4.4 Compilation date: 2012-11-27T22:44:52 ext2fs lib: 1.42.6, ntfs lib: libntfs-3g, reiserfs lib: 0.3.1-rc8, ewf lib: none /dev/sda: LBA, HPA, LBA48, DCO support /dev/sda: size 3907029168 sectors /dev/sda: user_max 3907029168 sectors /dev/sda: native_max 3907029168 sectors Warning: can't get size for Disk /dev/mapper/control - 0 B - CHS 1 1 1, sector size=512 /dev/sr0 is not an ATA disk Hard disk list Disk /dev/sda - 2000 GB / 1863 GiB - CHS 243201 255 63, sector size=512 - WDC WD20EARS-00J2GB0, S/N:WD-WCAYY0075071, FW:80.00A80 Disk /dev/sdb - 1013 MB / 967 MiB - CHS 1014 32 61, sector size=512 - Generic Flash Disk, FW:8.07 Disk /dev/sr0 - 367 MB / 350 MiB - CHS 179470 1 1 (RO), sector size=2048 - PLDS DVD+/-RW DH-16AAS, FW:JD12 Partition table type (auto): Intel Disk /dev/sda - 2000 GB / 1863 GiB - WDC WD20EARS-00J2GB0 Partition table type: EFI GPT Analyse Disk /dev/sda - 2000 GB / 1863 GiB - CHS 243201 255 63 Current partition structure: Bad GPT partition, invalid signature. search_part() Disk /dev/sda - 2000 GB / 1863 GiB - CHS 243201 255 63 recover_EXT2: s_block_group_nr=0/14880, s_mnt_count=5/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192 recover_EXT2: s_blocksize=4096 recover_EXT2: s_blocks_count 487593984 recover_EXT2: part_size 3900751872 MS Data 2048 3900753919 3900751872 EXT4 Large file Sparse superblock, 1997 GB / 1860 GiB Linux Swap 3900755968 3907028975 6273008 SWAP2 version 1, 3211 MB / 3062 MiB Results P MS Data 2048 3900753919 3900751872 EXT4 Large file Sparse superblock, 1997 GB / 1860 GiB P Linux Swap 3900755968 3907028975 6273008 SWAP2 version 1, 3211 MB / 3062 MiB interface_write() 1 P MS Data 2048 3900753919 3900751872 2 P Linux Swap 3900755968 3907028975 6273008 search_part() Disk /dev/sda - 2000 GB / 1863 GiB - CHS 243201 255 63 recover_EXT2: s_block_group_nr=0/14880, s_mnt_count=5/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192 recover_EXT2: s_blocksize=4096 recover_EXT2: s_blocks_count 487593984 recover_EXT2: part_size 3900751872 MS Data 2048 3900753919 3900751872 EXT4 Large file Sparse superblock, 1997 GB / 1860 GiB block_group_nr 1 recover_EXT2: "e2fsck -b 32768 -B 4096 device" may be needed recover_EXT2: s_block_group_nr=1/14880, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192 recover_EXT2: s_blocksize=4096 recover_EXT2: s_blocks_count 487593984 recover_EXT2: part_size 3900751872 MS Data 2046 3900753917 3900751872 EXT4 Large file Sparse superblock Backup superblock, 1997 GB / 1860 GiB block_group_nr 1 recover_EXT2: "e2fsck -b 32768 -B 4096 device" may be needed recover_EXT2: s_block_group_nr=1/14880, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192 recover_EXT2: s_blocksize=4096 recover_EXT2: s_blocks_count 487593984 recover_EXT2: part_size 3900751872 MS Data 2048 3900753919 3900751872 EXT4 Large file Sparse superblock Backup superblock, 1997 GB / 1860 GiB block_group_nr 1 recover_EXT2: "e2fsck -b 32768 -B 4096 device" may be needed recover_EXT2: s_block_group_nr=1/14584, s_mnt_count=0/27, s_blocks_per_group=32768, s_inodes_per_group=8192 recover_EXT2: s_blocksize=4096 recover_EXT2: s_blocks_count 477915164 recover_EXT2: part_size 3823321312 MS Data 4094 3823325405 3823321312 EXT4 Large file Sparse superblock Backup superblock, 1957 GB / 1823 GiB block_group_nr 1 ....snip...... MS Data 2046 3900753917 3900751872 EXT4 Large file Sparse superblock Backup superblock, 1997 GB / 1860 GiB MS Data 2048 3900753919 3900751872 EXT4 Large file Sparse superblock, 1997 GB / 1860 GiB MS Data 4094 3823325405 3823321312 EXT4 Large file Sparse superblock Backup superblock, 1957 GB / 1823 GiB MS Data 4096 3823325407 3823321312 EXT4 Large file Sparse superblock Backup superblock, 1957 GB / 1823 GiB MS Data 7028840 7033383 4544 FAT12, 2326 KB / 2272 KiB Mac HFS 67856948 67862179 5232 HFS+ found using backup sector!, 2678 KB / 2616 KiB Mac HFS 67862176 67867407 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 67862244 67867475 5232 HFS+ found using backup sector!, 2678 KB / 2616 KiB Mac HFS 67867404 67872635 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 67867472 67872703 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 67872700 67877931 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 67937834 67948067 10234 [EasyInstall_OSX] HFS found using backup sector!, 5239 KB / 5117 KiB Mac HFS 67938012 67948155 10144 HFS+ found using backup sector!, 5193 KB / 5072 KiB Mac HFS 67948064 67958297 10234 [EasyInstall_OSX] HFS, 5239 KB / 5117 KiB Mac HFS 67948070 67958303 10234 [EasyInstall_OSX] HFS found using backup sector!, 5239 KB / 5117 KiB Mac HFS 67948152 67958295 10144 HFS+, 5193 KB / 5072 KiB Mac HFS 67958292 67968435 10144 HFS+, 5193 KB / 5072 KiB Mac HFS 67958300 67968533 10234 [EasyInstall_OSX] HFS, 5239 KB / 5117 KiB Mac HFS 67992596 67997827 5232 HFS+ found using backup sector!, 2678 KB / 2616 KiB Mac HFS 67997824 68003055 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 67997892 68003123 5232 HFS+ found using backup sector!, 2678 KB / 2616 KiB Mac HFS 68003052 68008283 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 68003120 68008351 5232 HFS+, 2678 KB / 2616 KiB Mac HFS 68008348 68013579 5232 HFS+, 2678 KB / 2616 KiB Solaris /home 84429840 123499141 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84429952 123499253 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84493136 123562437 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84493248 123562549 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84566088 123635389 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84566200 123635501 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84571232 123640533 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84571344 123640645 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84659952 123729253 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84660064 123729365 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84690504 123759805 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84690616 123759917 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84700424 123769725 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84700536 123769837 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84797720 123867021 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84797832 123867133 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84812544 123881845 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84812656 123881957 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84824552 123893853 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84824664 123893965 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84847528 123916829 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84847640 123916941 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84886840 123956141 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84886952 123956253 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84945488 124014789 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84945600 124014901 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84957992 124027293 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84958104 124027405 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84962240 124031541 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84962352 124031653 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84977168 124046469 39069302 UFS1, 20 GB / 18 GiB Solaris /home 84977280 124046581 39069302 UFS1, 20 GB / 18 GiB MS Data 174395467 178483851 4088385 ..... snip (it keeps going on for quite a while)

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• Anatomy of a .NET Assembly - CLR metadata 2

  - by Simon Cooper

  Before we look any further at the CLR metadata, we need a quick diversion to understand how the metadata is actually stored. Encoding table information As an example, we'll have a look at a row in the TypeDef table. According to the spec, each TypeDef consists of the following: Flags specifying various properties of the class, including visibility. The name of the type. The namespace of the type. What type this type extends. The field list of this type. The method list of this type. How is all this data actually represented? Offset & RID encoding Most assemblies don't need to use a 4 byte value to specify heap offsets and RIDs everywhere, however we can't hard-code every offset and RID to be 2 bytes long as there could conceivably be more than 65535 items in a heap or more than 65535 fields or types defined in an assembly. So heap offsets and RIDs are only represented in the full 4 bytes if it is required; in the header information at the top of the #~ stream are 3 bits indicating if the #Strings, #GUID, or #Blob heaps use 2 or 4 bytes (the #US stream is not accessed from metadata), and the rowcount of each table. If the rowcount for a particular table is greater than 65535 then all RIDs referencing that table throughout the metadata use 4 bytes, else only 2 bytes are used. Coded tokens Not every field in a table row references a single predefined table. For example, in the TypeDef extends field, a type can extend another TypeDef (a type in the same assembly), a TypeRef (a type in a different assembly), or a TypeSpec (an instantiation of a generic type). A token would have to be used to let us specify the table along with the RID. Tokens are always 4 bytes long; again, this is rather wasteful of space. Cutting the RID down to 2 bytes would make each token 3 bytes long, which isn't really an optimum size for computers to read from memory or disk. However, every use of a token in the metadata tables can only point to a limited subset of the metadata tables. For the extends field, we only need to be able to specify one of 3 tables, which we can do using 2 bits: 0x0: TypeDef 0x1: TypeRef 0x2: TypeSpec We could therefore compress the 4-byte token that would otherwise be needed into a coded token of type TypeDefOrRef. For each type of coded token, the least significant bits encode the table the token points to, and the rest of the bits encode the RID within that table. We can work out whether each type of coded token needs 2 or 4 bytes to represent it by working out whether the maximum RID of every table that the coded token type can point to will fit in the space available. The space available for the RID depends on the type of coded token; a TypeOrMethodDef coded token only needs 1 bit to specify the table, leaving 15 bits available for the RID before a 4-byte representation is needed, whereas a HasCustomAttribute coded token can point to one of 18 different tables, and so needs 5 bits to specify the table, only leaving 11 bits for the RID before 4 bytes are needed to represent that coded token type. For example, a 2-byte TypeDefOrRef coded token with the value 0x0321 has the following bit pattern: 0 3 2 1 0000 0011 0010 0001 The first two bits specify the table - TypeRef; the other bits specify the RID. Because we've used the first two bits, we've got to shift everything along two bits: 000000 1100 1000 This gives us a RID of 0xc8. If any one of the TypeDef, TypeRef or TypeSpec tables had more than 16383 rows (2^14 - 1), then 4 bytes would need to be used to represent all TypeDefOrRef coded tokens throughout the metadata tables. Lists The third representation we need to consider is 1-to-many references; each TypeDef refers to a list of FieldDef and MethodDef belonging to that type. If we were to specify every FieldDef and MethodDef individually then each TypeDef would be very large and a variable size, which isn't ideal. There is a way of specifying a list of references without explicitly specifying every item; if we order the MethodDef and FieldDef tables by the owning type, then the field list and method list in a TypeDef only have to be a single RID pointing at the first FieldDef or MethodDef belonging to that type; the end of the list can be inferred by the field list and method list RIDs of the next row in the TypeDef table. Going back to the TypeDef If we have a look back at the definition of a TypeDef, we end up with the following reprensentation for each row: Flags - always 4 bytes Name - a #Strings heap offset. Namespace - a #Strings heap offset. Extends - a TypeDefOrRef coded token. FieldList - a single RID to the FieldDef table. MethodList - a single RID to the MethodDef table. So, depending on the number of entries in the heaps and tables within the assembly, the rows in the TypeDef table can be as small as 14 bytes, or as large as 24 bytes. Now we've had a look at how information is encoded within the metadata tables, in the next post we can see how they are arranged on disk.

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• First Foray&ndash;About timeout

  - by SQLMonger

  It has been quite a while since I signed up for this blog site and high time that something was posted.  I have a list of topics that I will be working through and posting.  Some I am sure will have been posted by others, but I will be sticking to the technical problems and challenges that I’ve recently faced, and the solutions that worked for me.  My motto when learning something new has always been “My kingdom for an example!”, and I plan on delivering useful examples here so others can learn from my efforts, failures and successes.   A bit of background about me… My name is Clayton Groom. I am a founding partner of a consulting firm in St. Louis Missouri, Covenant Technology Partners, LLC and focus on SQL Server Data Warehouse design, Analysis Services and Enterprise Reporting solutions.  I have been working with SQL Server since the early nineties, when it still only ran on OS/2. I love solving puzzles and technical challenges.   Enough about me… On to a real problem… SSIS Connection Time outs versus Command Time outs Last week, I was working on automating the processing for a large Analysis Services cube.  I had reworked an SSIS package and script task originally posted by Vidas Matelis that automates the process of adding new and dropping old partitions to/from an Analysis Services cube.  I had the package working great, tested, and ready for deployment.  It basically performs a query against the source system to determine if there is new data in the warehouse that will require a new partition to be added to the cube, and it checks the cube to see if there are any partitions that are present that are no longer needed in a rolling 60 month window. My client uses Tivoli for running all their production jobs, and not SQL Agent, so I had to build a command line file for Tivoli to use to run the package. Everything was going great. I had tested the command file from my development workstation using an XML configuration file to pass in server-specific parameters into the package when executed using the DTExec utility. With all the pieces ready, I updated the dtsconfig file to point to the UAT environment and started working with the Tivoli developer to test the job.  On the first run, the job failed, and from what I could see in the SSIS log, it had failed because of a timeout. Other errors in the log made me think that perhaps the connection string had not been passed into the package correctly. We bumped the Connection Manager  timeout values from 20 seconds to 120 seconds and tried again. The job still failed. After changing the command line to use the /SET option instead of the /CONFIGFILE option, we tested again, and again failure. After a number more failed attempts, and getting the Teradata DBA involved to monitor and see if we were connecting and failing or just failing to connect, we determined that the job was indeed connecting to the server and then disconnecting itself after 30 seconds.  This seemed odd, as we had the timeout values for the connection manager set to 180 seconds by then.  At this point one of the DBA’s found a post on the Teradata forum that had the clues to the puzzle: There is a separate “CommandTimeout” custom property on the Data source object that may needed to be adjusted for longer running queries.  I opened up the SSIS package, opened the data flow task that generated the partition list table and right-clicked on the data source. from the context menu, I selected “Show Advanced Editor” and found the property. Sure enough, it was set to 30 seconds. The CommandTimeout property can also be edited in the SSIS Properties sheet. In order to determine how long the timeout needed to be, I ran the query from the task in the development environment and received a response in a matter of seconds.  I then tried the same query against the production database and waited several minutes for a response. This did not seem to be a reasonable response time for the query involved, and indeed it wasn’t. The Teradata DBA’s adjusted the query governor settings for the service account I was testing with, and we were able to get the response back down under a minute.  Still, I set the CommandTimeout property to a much higher value in case the job was ever started during a time of high-demand on the production server. With this change in place, the job finally completed successfully.  The lesson learned for me was two-fold: Always compare query execution times between development and production environments, and don’t assume that production will always be faster.  With higher user demands, query governors, and a whole lot more data, the execution time of even what might seem to be simple queries can vary greatly. SSIS Connection time out settings do not affect command time outs.  Connection timeouts control how long the package will wait for a response from the server before assuming the server is not available or is not responding. Command time outs control how long a task will wait for results to start being returned before deciding that the server is not responding. Both lessons seem pretty straight forward, and I felt pretty sheepish once I finally figured out what the issue was.  To be fair though, In the 5+ years that I have been working with SSIS, I could only recall one other time where I had to set the CommandTimeout property, and that memory only resurfaced while I was penning this post.

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• Disaster Recovery Discovery

  - by Rodney Landrum

  Last weekend I joined several of my IT staff on a mission to perform a DR test in our remote CoLo center in a large South East city of the US. Can I be more obtuse? The goal was simple for me as the sole DBA in a throng of Windows, Storage, Network and SAN admins – restore the databases and make them work. There were 4 applications that back ended to 7 SQL Server databases on 4 different SQL Server instances. We would maintain the original server names, but beyond that it was fair game. We had time to prepare so I was able to script out or otherwise automate the recovery process. I used sp_help_revlogin for three of the servers, a bit of a cheat actually because restoring the Master database on the target DR servers was the specified course of action according to the DR procedures ( the caveat “IF REQUIRED” left it open to interpretation. I really wanted to avoid the step of restoring Master for a number of reasons but mainly because I did not want to deal with issues starting SQL Services afterward. Having to account for the location of TempDB and the version conflicts of the resource DBs were just two of the battles I chose not to fight. Not to mention other system database location problems that might arise and prevent SQL from starting.  I was going to have to restore all of the user databases anyway, so I would not really gain any benefit, outside of logins, for taking the time to restore the source Master database over the newly installed one on the fresh server. What I wanted was the ability to restore the Master database as a user database, call it Master_Mine, from a backup on the source system and then use that restored database to script the SQL Logins and passwords on the DR systems. While I did not attempt this on the trip, the thought stuck in my mind and this past week I succeeded at scripting user accounts and passwords using only a restored copy of the Master database. Granted there were several challenges to overcome.  Also, as is usual for any work like this the usual disclaimers apply:  This is not something that I would imagine Microsoft would condone or support and this was really only an experiment for me to learn if it was even possible. While I have tested the process with success, I do not know that I would use this technique in a documented procedure because future updates for SQL Server will render this technique non-functional. I thought at first, incorrectly of course, that I could use sp_help_revlogin on a restored copy of the master database I named Master_Mine.   Since sp_help_revlogin uses system schema objects, sys.syslogins and sys.server_principals, this was not going to work because all results would come from the main Master database. To test this I added a SQL login via SSMS, backed up Master, restored  it as Master_Mine, and then deleted the login.  Even though the test account I created should presumably still be in the Master_Mine database, I should be able to get to it and script out its creation with its password hash so that I would not need to know the password, but any applications that stored that password would not have to be altered in the DR scenario. They would just work as expected. Once I realized that would not work I began looking deeper.  Knowing that sys.syslogins and sys.server_principals are system views, their underlying code should be available with sp_helptext, right? They were. And this led me to discover the two tables sys.sysxlgns and sys.sysprivs, where the data I needed was stored. These tables existed in both the real Master and the restored copy, Master_Mine.  I used this information to tweak the sp_help_revlogin stored procedure to use these tables instead to create the logins cursor used in sp_help_revlogin. For the password hash,  sp_help_revlogin uses the function LoginProperty() which takes a user name and option ‘passwordhash’ to return the hash for the user. Unfortunately, it requires the login to exist in the Master database. This would not work. So another slight modification I had to make was to pull the password hash itself (pwdhash from sys.sysxlgns) into the logins cursor and comment out the section of sp_help_revlogin that uses LoginProperty. Instead, I pass the pwdhash value as the variable @PWD_varbinary to the sp_hexadecimal stored procedure which is also created by and used within the code provided by Microsoft in the link above for sp_help_revlogin. The final challenge: sys.sysxlgns and sys.server_principals are visible only within a Dedicated Administrator Connection (DAC) query window in SSMS or within SQLCDMD.  To open a DAC connection you have to be logged in on the SQL Server itself, via RDP in my case,  and you preface the server name in the query connection with ADMIN:, so that the server connection looks like ADMIN:ServerName. From there you can create the modified stored procedure in the restored copy of a Master database from a source system as whatever name you like, and then run the modified stored procedure. I named my new stored procedure usp_help_revlogin_MyMaster. Upon execution I was happy to see the logins and password hashes that I needed to apply from the source Master database without having to restore over the new Master system database and without the need to access the original server (assuming it was down due to whatever disaster put it in that state). You will note that I am not providing full code samples here of the modifications. I will say that it was a slight bit of work and anyone who needed to do this for whatever reason, could fairly easily roll their own solution with the information provided herein.  My goal, as I said was to prove that this could be done and provide another option if required to ease the burden of getting SQL Servers up and available in an emergency situation where alternatives may be more challenging or otherwise unavailable.  

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