After moving all my solutions over to a newly installed machine (which makes me think this is a config issue), I am now having this problem with my MVC 5 web application(s).
When I build my web application (VS 2013), this of course regenerates all the web code and IIS will restart the application on next page load. However now it seems, when I go to my start/login page, the Application_Start() fires as expected, but when the page is submitted, before the HttpPost method is reached, the entire application seems to start again (Application_Start runs again). This second start seems to occur before the first Application_End() is called...but regardless of the sequence I have no idea why this is now an issue.
Checking the application shutdown reason in Application_End() I get the notorious vague (and apparently completely undocumented) "BuildManagerChange"...which MSDN gives some ridiculously vague description of.
Does anybody have idea why this would start after loading my development environment onto a new machine. Both machines are Win7 Pro running IIS7.5, and I believe the IIS config is identical to the old one (though, apparently not??). The source code/web.config/etc has not changed between machines.
The only documentation I could find on this issue was in regards to using IISExpress, however I am using the standard IIS7.5 installed with Win7 pro.
Edit: After removing all custom code from the entire startup of the site, and reverting my LoginController back to it's original simple form (no custom code), this still occurs.
Well, wasting 2 days on this was fun! But, this was resolved. Running procmon showed that hash.web was being accessed by mcshield.exe (McAfee AV). Apparently the live "on access scanner" checks the asp.net cache, and somehow IIS is aware of this and thinks it needs to rebuild the site again. For some reason McAfee does not check it after this first time so it functions normally after a second build/restart. I added a scanner exclusion to the c:\Windows\Microsoft.NET folder, and that seems to have solved the issue. –
A bit late to the party, but maybe it'll help someone. For me it was because I accidentally mapped two IIS sites to one directory. This resulted in two IIS background worker tasks and Application Application_Start() being called twice even though the second site was marked as "Stopped" in IIS.
Related
We are developing an (internal) web service based on asp.net 4.8, with a fairly extensive REACT SPA front end.
For debugging purposes during development, we run an IIS server on the local (development) machine, and we do something separate to run a proxy web server for debugging the .js front end SPA (not relevant to the question at hand).
When we start up a Debug session in Visual Studio (2019), VS starts with "Contacting web server to start debugging" and then locks for a time. It clearly does something to start the web server (w3wp.exe), and waits for some reply, before doing what it is told to do in the "Start Action" section of the Web tab on the project properties page.
This is problematic behaviour because it does not attach to w3wp.exe until after it finishes it's "contacting web server to start debugging" operation. This is a huge problem, as our w3wp.exe starts doing all kinds of things that we have no visibility into.
So, can anyone explain to me:
What does VS actually do to "contact the web server"?
Can this be controlled? If so, how?
Can I get the debugger to attach to w3wp.exe right away?
Why does w3wp.exe start up and load its collection of binaries, only unload them and reload them, sometime multiple times?
In short, what the actual heck is going on under the covers at startup?
This (Identity Server 3 Contacting the web server hangs when launching debug mode) question and answer seem irrelevant to my situation
I note the field Override application root URL in the Servers section of the Web tab of the project properties and had hoped this might have something to do with it, but I cannot see any relation.
Partial answers that I will either edit as I find more info, or modify if others correct me, or delete if someone answers completely. The answers to (1) and (2) above are this:
VS obtains the URL of the target web site (I will call this targetServer) from the Project URL entry in the Servers section, Web tab, of the Properties page for the web project. This actually comes from the <webProjectName>.csproj.user file in the project directory. Depending on the selection of the drop down specifying the server type to use, it comes from:
IIS server (<UseIIS>true): the <IISUrl> element
External Host (<UseCustomServer>true): the <CustomServerUrl>
IIS Express: unknown
WARNING: When opening a project with <UseIIS>true, Visual Studio has the very nasty habit of interfering in the setup of your IIS server: it insists on changing the "Physical Location" attribute of the IIS server (that is, the server or virtual app, however you have it set up) to point to the project directory of the web project. Using the "External Host" option avoids this - see https://stackoverflow.com/a/48753054/1082063. (All other discussions of this issue that I have seen incorrectly say this cannot be controlled.)
VS then issues a request to the url <targetServer>/debugAttach.aspx, and the request shows as neither a "GET" nor a "POST", but a "DEBUG", whatever that is. Not sure what VS expects back from this before doing the specified Start Action
Presumably after VS gets some reply from its DEBUG request, it will attach to the process that resulted from this request. Not sure how it knows which process to attach to - perhaps the debugAttach.aspx returns process information?
VS finally executes whatever Start Action is specified in the section of that name on the Web tab of the project Properties.
I strongly suspect that the answer to (3) above is that one cannot get VisualStudio to attach any earlier than it does because it must use the information returned from the debugAttach.aspx request to know which process to attach to. However, putting the line System.Diagnostics.Debugger.Launch(); at the start of Application_Start will allow you to attach the debugger earlier when necessary. (In practice, once you get Application_Start correct, you seldom need to debug it.) See this: https://weblog.west-wind.com/posts/2011/Dec/15/Debugging-ApplicationStart-and-Module-Initialization-with-IIS-and-Visual-Studio for a very good article on the subject.
(4) was a result of quirks in our Visual Studio setup. The initial "hack" used to get around the WARNING in answer (2) just above, was to have a web site with a dummy "virtual path" and have the IISUrl element in Visual Studio point to this virtual path. Then VS could change the Physical path of this virtual path, and we didn't really care, because our Start Action was to start a proxy server for debugging .js in any case. The issue was that this resulted in two calls to Application_start, running on two separate threads: one for the main server and one for the virtual server. Because one of these was happening before the attach happened, we never knew it was happening and it was never caught in a break point. When our application_start became long (timewise - this is not a web server for public consumption...), the two executions of application_start became a nightmare.
The issue you're seeing in IIS is that VS is not launching w3wp.exe, but rather Attaching to Process. In order for VS to attach though the EXE has to be running first, and the time between starting up and attaching (if not already running) ends up being too late to catch the ASP.NET app initialization logic in Application_Start and Module initialization.
As mentioned in my old post there are several ways you can get this to work:
Restarting the application when the debugger is already attached
(by making a change in web.config to trigger an AppDomain reload)
Adding an explicit Debugger.Break() call in Application_Start
Use IIS Express to debug startup code
It may be a silly question but why one would like to attach debugger to IIS instance?
These SOs
Attach Debugger to IIS instance
How do I attach the debugger to IIS instead of ASP.NET Development Server?
show you how to do it but could you let me know what are the benefits of doing this?
One time, in my entire career, we had a web app that started getting strange errors that had us baffled. We tried a dozen things to try and figure out what was wrong, but we were panicking and needed an answer immediately. So, we attached a debugger to the production instance and set up a few watch/break points. It helped us track down the errors and fix the problem.
Naturally, it hung the server during our debugging session, and made people mad, but no more mad than they already were, because of the problem we had.
It would not have been necessary if the code had been written better, with error logging and diagnostic points. I don't expect to ever do it again.
Apart from TimG's post a couple of reasons I can think of are:
To debug the application in a closer representation of its
production environment
To debug on a remote machine
Example, like #TonE #1 -- in order to test a deployed website (with web.config transformations) locally, like if you can't remote debug a live website or just need to test config transforms (since you can't run them in-place):
Open site project from C:\Dev\AwesomeWebSite\AwesomeWebSite.sln
Publish the site to a local folder C:\Webs in Release mode (or Whatever mode)
Set up a local IIS website pointing at the published project
Do stuff on the locally-deployed version (e.g. browse pages, make webservice calls, etc)
Attach VS to w3p.exe (appropriate instance) in order to debug the deployed version
You might be able to effectively do the same thing by instead pointing the Project at your IIS website per this answer.
A former employee implemented a custom VB.Net Context class that inherits DictionaryBase and implements ILogicalThreadAffinitive. The class object maintains values such as user ID, language, location, etc. throughout the user's session in an ASP.NET web application with .NET 4 Framework.
<Serializable()> _
Public NotInheritable Class Context
Inherits DictionaryBase
Implements ILogicalThreadAffinative
... Class Methods ...
End Class
The object class seems to work fine, holding the values as expected when navigating from page to page, even when loading a popup page. My issue arises anytime I have a PostBack action. When this occurs, the object becomes null and causes null reference errors.
The strange part is that it works for everyone except me. It's installed on our client's system, runs in our test environment, and works for our other developer on the project, but there's something preventing it from working in my development environment, which hosts the application with the local IIS 7.0 web server. The other developer and I have cross-checked all of the local IIS settings, VS2010 settings, and internet options that we would have altered, but everything appears to be identical between the two machines (both Win7 x64, building the application in x86 mode). Needless to say, this issue has become very prohibitive for development and troubleshooting issues.
Are there any suggestions as to what else can be checked that might produce such behavior?
EDIT: After some more advanced digging, it appears the PostBack is causing a request to fire on a second thread. This second thread, despite what documentation seems to say, does not carry over the values in the CallContext. On my colleague's working environment, this request is handled on the same thread. This seems to be the main symptom of the problem, but we still cannot pinpoint the source. Also, perhaps of note: my machine has an SSD and the other developer does not. I don't know if that affects threading, but I don't think it would produce these results.
I'm not particularly satisfied with the solution, but I was able to run the program without errors by switching to the ASP.NET v4 Classic Application Pool. As stated before, my colleague's machine is running the program just fine with the Integrated Application Pool. On my machine, however, this causes threading issues.
So, not a satisfactory "answer" per se; but I have a solution, nonetheless.
I have an application that runs perfectly fine locally using the VS 2010 application server, however, when I deploy to our web app machine startup just spins and spins and never loads. We have other apps on this same machine that load just fine (this is a debug deployment of same app in product).
I have been spinning my wheels on this for days and I am at a loss as the problem could be.
Here is what I did
Create a new directory (same level as other apps)
Copied over our existing test (www.domain/test/) and it works fine
Build and publish new debug app (www.domain/test/) and it just spins trying to load first form.
I know the diretory is "working" as the 'test' application I put there works fine.
If it's killing the App pool, you might get something in the event log. Fiddler (www.fiddlertool.com) is great http debug tool which let you see if you're in a redirect loop. Also Firefox shows a more meaningful error, something about exceeding the max redirect count.
It does sound like something is looping, but not quick enough to cause a stack overflow, which is odd, because you'd expect it to fail every time.
Simon
Do you have the ability to remote desktop into the machine? If so try running process explorer and look at the process details for the worker process that is giving you issues. Definitely look at the TCP connections being created. If your processor is pegged at 100%, and memory usage is rising then you probably have an endless loop running.
It sounds like it's more related to IIS than ASP.NET. What about the identity that the website is running under? Is it possible that the user the site's running under a bad user, or maybe the password needs to be re-entered?
I did a quick Bing search
There are a lot of postings regarding the error message you described above. Most if not all point to code in your app that is crashing. I know I had a similar problem when I used an automated/threaded daemon utility in my web application. Make sure your code is not bringing down the server, sometimes the VS2010 web server is a little more foregiving than an actual IIS deployment.
If that doesn't work try running a Remote Debugging Session to try and catch any errors being thrown but not handled.
Lastly you could try to setup a new local IIS server to see if you have the same problems. Scott Gu has a nice article about using IIS Express to do this.
I deployed an ASP.NET web application last night and I when I woke up this morning it was very slow and would occasionally just throw a 'Service Unavailable' error.
I checked the Event Viewer and it was filled up with these errors:
An unhandled exception occurred and the process was terminated.
Exception: System.Runtime.Serialization.SerializationException
Message: Unable to find assembly 'MonoTorrent, Version=0.80.0.0, Culture=neutral, PublicKeyToken=null'
I'm puzzled as it was working perfectly when I deployed it (MonoTorrent is required to retrieve the number of seeders/leechers for a certain torrent off the tracker - this was working fine), but it's no longer working and whenever code that uses MonoTorrent gets involved, the worker process just crashes.
MonoTorrent.dll is in the /bin/ directory.
UPDATE 6/4/10: I compiled the MonoTorrent source code in with the rest of my web application, but it still crashes whenever it uses MonoTorrent. However, it now says that it is Unable to find assembly 'OpenPeer, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null. Here, OpenPeer is the name of the web application's assembly.
This can happen in these circumstances:
The ASP.NET app creates a background thread, which throws an uncaught exception. It looks like ASP.NET catches the exception and wants to log it to the Event Log. To do this, it sends this exception from the Web app's app domain to its own app domain (the default one of the w3wp process). This needs a serialization/deserialization of the exception.
If the exception is a custom one (i.e. defined by the Web app), it cannot be deserialized in the main app domain of ASP.NET because the assembly defining the exception is typically in the Web app's bin directory, not where w3wp.exe is (c:\windows\system32\inetsrv). This causes a serialization exception and w3wp crashes.
There are possible ways to fix the issue (in a - very subjective - order of preference):
Copy the missing DLL in c:\windows\system32\inetsrv
Install the missing DLL in the GAC
Remove the cause of the exception (harder to do than to say, as we say in French)
Catch all exceptions from the background thread yourself and do the logging yourself.
Notes:
If WCF is used and the uncaught exception is FaultException, WCF swallows it and there is no crash
If the uncaught exception is in the thread of the Web request, there is a yellow screen of death, not this serialization exception
It really seems like a bug in ASP.NET
The above is actually a summary of my investigations of this issue yesterday and are only a theory. I tested fixes 1 and 4, as well as using FaultException.
Here are some things you can try..
1.) Flush ASP.Net Temp directory. Restart IIS and recycle Application pool.
2.) Make sure your web-application is running in FULL-TRUST if it really needs FULL-TRUST.
3.) Take the Assembly, try to use it in other asp.net application and run the test application on a seperate server. This might help you diagnose the problem. Also try to run the test asp.net app on the same server but in seperate application pool.
4.) Make sure the IIS website of your application is running under the user account with necessary security priviliges. Try running the application under Administratotr as user.
EDIT-1
5.) Also check if the assembly version is the same as mentioned in web.config. If there's a version mismatch then you can do AssemblyBinding Redirection in web.config.
6.) Also try registaering the Assembly in GAC and see if it loads properly.
EDIT-2
7.) Try reconfigring ASP.NET support on the server or maybe framework runtime re-setup may help. This may not be a sure-shot solution but looking at the problem condition we may want to try various solutions.
8.) Make sure you're not missing any critical update of your windows server platform.
I try to give you some ideas - what I do if I was on your position.
First of all I take a long look of the MonoTorrent.dll before some days that you make your question, and I look it again today. I found and the function that load the dll. My first opinion is that something have to do with the permissions.
I hope that you have access to the server - right ?
My first steps is that:
Ensure that your monotorrent.dll actuall have the right permissions to the bin directory, for Read, and execute by your asp.net app. Some times the copy of one dll, did not get the directory permissions buts carriage out his own permissions. To check if your dll have different permissions from the rest, just right click and see Properties | Security, then go to bin directory and do the same, and compare the Security permissions. If they are different then apply again the Directory permissions and make sure that the dll inherited by the directory.
My second step
Download the ProcessMonitor from sysinternals
http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx
Run ProcessMonitor and try to recreate the error, stop it and analyse to see where and why the dll gets the denied permissions to run.
With the ProcessMonitor you can even see if there is any dll that can not found !
I have check the MonoTorrent dlls and I do not found anything unusual. He have kerner32.dll calls, and use unsafe code to run, ok nothing so special about.
So if you do that 2 steps and give me some feedback, maybe I can go further. (if not solve by you and what you find)
I would advice to setup Regular maintanence probably once in a week at sunday night etc for following,
Delete all temporary files
Delete all ASP.NET IIS temporary files
Restart Server
Problem is, ASP.NET web apps cause lot of temp files to be left in the disk, because of dynamic compilation of regex, seriliazation assemblies etc, such temp stuff never gets deleted, and more and more junk starts getting collected in temp locations, ASP.NET goes slower and slower, and a point comes in where disk as well as memory defragmentation reaches very high point, things start to fail.
No body likes to restart server once a week, but I remember we had no choice, in ASP.NET 1.1 we had stable system after restarting every day, in ASP.NET 2.0 onwards, we are good to have restarting scheduled at once a week.
I have found this problem and I have do all of thing as I can, such as clear temp file, restart server, delete and add reference and I also rebuild the solution. However I can't solving this problem. Finally I move my entity class (almost of them need to serialize) to new folder that I have added to the project and then this problem solved.
This method is work for me.
Try clearing the ASP.NET temp files. It's solved some odd issues before for me.
Otherwise, Fusion-logging may shed some light.
UPDATE: #Charlie - I'm not sure what to make of those logs...it looks like the failed log is from a different AppDomain. Notice the AppBase is set to "file:///c:/windows/system32/inetsrv/" and AppName is w3wp.exe.
I'm pretty sure the Event Viewer should show Application Id: LM/W3SVC/#/ROOT if it was the default AppDomain, too. At this point, all I've got is random guesses.
I notice you're running x64...does MonoTorrent perhaps require x86?
Have you double checked that the directory is an IIS application, and is configured for the correct version of ASP.NET?
Is there some other application that uses MonoTorrent on this server? Maybe a WCF service or something? I'm not sure where the Serialization is happening....
Try hooking the AssemblyResolve event and loading it manually.
Can you repro on a development machine? If not, maybe it's a borked FX install. Uninstall and reinstall.
Does restarting, recycling or stopping/starting the AppPool fix the issue temporarily, or cause the issue to appear?
You may want to type out your screenshot text too so you'll get some Google love....
Is the server timezone different than your timezone? I've had this issue when deploying resource files, the compile time was in the future so they would fail to load.
My guess that you have plenty of open but not closed connections. I mean the connections are not returned to the pool. It looks okay, when you start the application, but after some time there are only several sockets available in the pool and it goes slow. Another thing - non-closed connection may keep DLL in memory, not allowing to release the handler. Try to debug object destruction.
I know it's simple but I had this problem once and itwas because I had a Web Application project which contains
References
Folder and I just copied my files into a
Bin
folder, in any .net web application in the Project Properties windows, a Reference Path tab is available which by default should nothing be include on it. check this option and also Build tab in Project Properties window which Output path be as the same as bin\