IIS7 fails to load aspx pages - asp.net

I've been trying to migrate a fairly large web application from IIS6 to IIS7 the past few days, but every time it seems like we're about done, IIS7 fails to load aspx pages.
The application is a .net 3.5 webapp that makes heavy use of reflection and web services. We use 2 main components (each with their own web site in IIS7 although they share an application pool): the web UI (aspx pages), and the webAPI (asmx pages).
The webAPI portion runs perfectly (as far as we can tell; there are a few things we can't test from the browser), and the web UI pages load static HTM pages just fine. The problem is that once we attempt to view an aspx page (any aspx page), the whole thing just comes to a halt; no error is logged in the event viewer until a few minutes later when we get an IIS 5010 warning (worker process ignoring ping).
We've attempted to migrate the app in two different ways:
Manually: we moved all the necessary files and set up the virtual directories then converted them to Web Sites. Result: the worker process took up 100% of a single core and spun forever (until terminated manually)
Automatically: Utilizing the MSDeploy application from www.iis.net we archived the entire IIS6 web server and unpacked it into a blank IIS7 install. We had to turn off Forms Auth to get rid of a 401.2 error, but after that the result here was that the webAPI component still works just fine, but instead of the web UI worker process taking up 100% of a single core, it grew to about a third of the required memory then hung out doing nothing.
Either way, what happened from the user's point of view was the same.
Unfortunately, we can't even attach a debugger to the worker process because it doesn't seem to be loading managed code.
Details:
.net framework: v3.5
CLR version: v2.0
IIS Authorization mode: Anonymous
OS arch: x64
App arch: x86
Happens with both classic and integrated pipelines
Notes:
New web projects seem to work just fine in IIS7 and, of course, xml web services are also fine
temporary DLLs are created and stored in the temporary ASP.net DLLs folder, even though the worker process never seems to contain managed code.
New pages added to the web UI project also show the same behavior (Didn't hurt to try)
Updates:
We've narrowed down the problem to a single assembly. It's a wrapper for a third party web control. I'm looking into replacing it, we'll see if it fixes the problem.

http://support.softartisans.com/kbview.aspx?ID=1318
Turns out it was an issue with the vendor control. Wish their solution actually worked though...

Try to re-register ASP.NET:
http://msdn.microsoft.com/en-us/library/k6h9cz8h(VS.80).aspx
The typical command line syntax would be to command line to the ASP.NET 2.0 version of your framework and type:
aspnet_regiis -i

Are you using the "Classic" Pipeline Mode for your Application Pool. The "Integrated" one is the default in IIS7 and it introduced changes in terms of configuration. (One example is HttpHandlers that need a different configuration in web.config).
The "Classic" one mimics the IIS6 application pool, and should work with the same configuration as for IIS6.
If you prefer to use the Integrated Pipeline, there are some tools that will automatically try to convert you configuration files.
Scott Hanselman covers some of these tools in his blog post.

Related

Prevent sharing DLL in IIS/ASP.net

lets say I have two ASP MVC applications.
ProjectXXX
ProjectYYY - this is fork of ProjectXXX.
Both projects have same structure (project/assembly name), but it differs on some functionality (it will be deployed for other countries).
For testing purposes we deploy both applications on one server.
ProjectXXX - has own IIS pool
ProjectYYY - has own IIS pool
Problem
When I removed some functionality from assembly of ProjectXXX and run ProjectYYY it throws TypeLoadException : Could not load type 'Project.Namespace.IMyInterface' from assembly 'Project.Namespace'
It looks like ProjectYYY uses DLL from ProjectXXX (IIS (asp.net?) loads dll once, because it "thinks" assemblies are the same?)
How to force IIS not to cache those assemblies and load the proper one for both apps?
EDIT / SOLUTION:
I have found, that my application uses MEF composition. As for now I have changed how it searches for assemblies and problem looks like gone :)
if you create separate IIS Site for each, it should do the trick, as for each site a separate w3wp process is run. Having said that, you can't share same ip and port for 2 sites so if you need that, you'll have to play around with redirecting, url rewriting on IIS.

IIS App Pool/Restart and ASP.NET

We are using IIS7 to host an asp.net web-based application.
In this environment administrators and developers can deploy code to the application on a regular basis.
The new code or app goes as a DLL to the ASP.NET bin folder. Upon deployment of the new DLL, IIS restarts the process, impacting (slowing down) all online users.
Is there a way to configure IIS to run the process in the background and once ready make the switch from old state into new without impacting the users?!
Thanks in advance for your feedback!
IIS already does this, that's what recycling is all about. IT's loading the DLL's while the old version of the application is still running. only after this is completed the recycling is complete.
However loading the DLL's is only part of getting web applications ready, there might also be initial loads like loading/caching the user db etc.
These actions are not part of the recycle process, they happen after all DLL's reloaded and the recycling is already completed.
A while back I ran into this issue with an application that had a huge startup time due to heavy db activity/caching during startup. So I was interested if there is some functionality that allows us to execute code before the recycle is marked as completed, so that the application is first considered recycled when everything is ready to run. Basically what I wanted is some kind of staging functionality.
I was in contact with the IIS team regarding this issue, sadly they told me that no such functionality exists, nor is it planned.
To solve this you could try do the following:
Use alternating deploys:
You setup 2 Websites with separate application pools. One of them is the LIVE website the other one is the STAGED website. If you want to deploy changed you simply deploy to the STAGED website. After everything is loaded/cached etc. you switch the URL settings of the web applications to reroute incoming requests from the LIVE to the STAGED one. So the LIVE one becomes the new STAGED and the other way around. The next deploy would then go to the new STAGED again and so on.
UPDATE
Apparently they have created a IIS Module that provides this functionality by now:
IIS Application Warm-Up Module for IIS 7.5
The IIS team has released the first beta test version of the
Application Warm-Up Module for IIS 7.5. This makes warming up your
applications even easier than previously described. Instead of writing
custom code, you specify the URLs of resources to execute before the
Web application accepts requests from the network. This warm-up occurs
during startup of the IIS service (if you configured the IIS
application pool as AlwaysRunning) and when an IIS worker process
recycles. During recycle, the old IIS worker process continues to
execute requests until the newly spawned worker process is fully
warmed up, so that applications experience no interruptions or other
issues due to unprimed caches. Note that this module works with any
version of ASP.NET, starting with version 2.0.
For more information, see Application Warm-Up on the IIS.net Web site.
For a walkthrough that illustrates how to use the warm-up feature, see
Getting Started with the IIS 7.5 Application Warm-Up Module on the
IIS.net Web site.
See:
http://www.asp.net/whitepapers/aspnet4
If you use ASP.NET 4 Auto Start feature:
You can still choose to auto-recycle the worker processes from time to
time. When you do that, though, the app will immediately restart and
your warm up code will execute (unlike today - where you have to wait
for the next request to-do that).
The main difference between Warm Up and Auto Start feature is that the Warm Up Module is part of the recycling process. Rather than blocking the application for requests, while running the init code.
Only thing you get by using the Auto Start feature is that you don't have to wait for a user to hit the page, which does not help your case.
See the Gu's blog post:
http://weblogs.asp.net/scottgu/archive/2009/09/15/auto-start-asp-net-applications-vs-2010-and-net-4-0-series.aspx
UPDATE 2:
Sadly the Warmup Module has been discontinued for IIS 7/7.5:
http://forums.iis.net/t/1176740.aspx
It will be part of IIS8 though (It's now called Application Initialization Module):
http://weblogs.asp.net/owscott/archive/2012/03/01/what-s-new-in-iis-8.aspx
UPDATE 3:
As pointed out in the comments the Warmup Module resurfaced for IIS 7.5 as Application Initialization Module for IIS 7.5 after IIS 8 was released:
http://www.iis.net/downloads/microsoft/application-initialization
The first part of ntziolis answer is a wee bit inaccurate. The worker process isn't being recycled or restarted, it just keeps running. If this were the case, then in shared pool environments you would have sites knocked out every time a new one was deployed.
When you deploy a new ASP.NET application it's the site's "Application Domain" within the worker process is torn down, not the pool process.
In addition pool recycling is a completely separate concept to deployment
At this point in time in the commercial life of ASP.NET, during a deployment, a site will be in an inconsistent state until all of the site is deployed. There is still no good story about this from Microsoft at this time for single site on a single server deployments.
This is why ASP.NET has the special App_Offline.htm page. It's there so you can enable that page, deploy and then turn it off.
The second part of ntziolis answer is nearly correct but you don't need two sites or two application pools. You just need two file system folders that switch between being the physical folders for the site...if you're on a single server and not behind a load balancer or ARR.
If your sites were on a web server behind a load-balancer or ARR then having two different sites would make sense, you could route requests from one site to the other and round-robin on each deploy.
Obviously if there is a large amount of user generated content (uploaded files and the like) then you'd map a virtual directory in your site to a common location for this data.
In larger scale deployments where your app is running across (for example) a load-balanced environment you can do more sophisticated deployments.
For related questions please see:
How Do I deploy an application to IIS while that web application is running
Publishing/uploading new DLL to IIS: website goes down whilst uploading
Is smooth deployment possible with componentized ASP.NET MVC apps?

Publishing a simple .NET web service yields IIS "It is an error to use a section registered as allowDefinition='MachineToApplication' ..."

This error has been reported elsewhere on stackoverflow, but none of the answers seem applicable to my situation.
I'm publishing a simple .NET web service (.asmx) and when I check the link in production, I'm met with the famous error:
"It is an error to use a section registered as
allowDefinition='MachineToApplication' beyond application level. This
error can be caused by a virtual directory not being configured as an
application in IIS."
I've gone through the basics already, namely these three most popular hints:
1/ The directory has been created as an "Application" by right-clicking in IIS, et cetera. It's running in its own Application pool.
2/ There is no subdirectory containing any superfluous web.config files. It's just the one web.config.
3/ I've made sure that the namespace matches up with the web service definition, all that basic stuff. At any rate, the project runs fine locally and also runs fine when deployed to a test server. This is leading me to think 'permissions issue' on the prod server, but I'm at a loss since the normal IIS sites run fine.
So I guess what I'm asking is: is there a fourth-most-popular cause of this error that I"m missing?
Oh, the Web Service Application is set to allow web service calls for all versions of .NET installed on IIS.
Also, I'd be happy to leave this legacy approach behind and ditch the .asmx for WCF; however this is the piece of code I'm tasked with rolling out at present.
Thanks!
You need to make sure that your have the proper .net framework version selected in you Application Pool. You can check this by going into IIS manager and going to the Application Pools node. Right click on the application pool that is attached to the website that contains your service and select "Basic Settings" (this choice should be in the left hand column of the window too). Then from the drop down select the proper version of the framework. You might need to create a new application pool specifically for the child application if they need to operate on different versions of the framework.
If the parent site is using .net 4.0 your webservice is probably inheriting that or vice versa (2.0).
So in short, try switching your application pool to a different framework version and see if that clears it up.

Mixing .NET versions between website and virtual directories and the "server application unavailable" error Message

Backstory
Last month our development team created a new asp.net 3.5 application to place out on our production website. Once we had the work completed, we requested from the group that manages are server to copy the app out to our production site, and configure the virtual directory as a new application.
On 12/27/2010, two public 'Gineau Pigs' were selected to use the app, and it worked great.
On 12/30/2010, We received notification by internal staff, that when that staff member tried to access the application (this was the Business Process Owner) they recieved the 'Server Application Unavailable' message.
When I called the group that does our server support, I was told that it probably failed, because I didn't close the connections in my code. However, the same group went in and then created a separate app pool for this Extension Request application. It has had no issues since.
I did a little googling, since I do not like being blamed for things. I found that the 'Server Application Unavailable' message will also appear when you have multiple applications using different frameworks and you do not put them in different application pools.
Technical Details - Tree of our website structure
Main Website <-- ASP Classic
+-Virtual Directory(ExtensionRequest) <-- ASP 3.5
From our server support group:
'Reviewed server logs and website setup in IIS. Had to reset the application pool as it was not working properly. This corrected the website and it is now back online. We went ahead and created a application pool for the extension web so it is isolated from the main site pool. In the past we have seen other application do this when there is a connection being left open and the pool fills up. Would recommend reviewing site code to make sure no connections are being left open.'
The Real Question:
What really caused the failure? Isn't the connection being left open issue an ASP Classic issue? Wouldn't the ExtensionRequest application have to be used (more than twice) in the first place to have the connections left open? Is it more likely the failure is caused by them not bothering to setup the new Application in it's own App Pool in the first place?
Sorry for the long windedness
You'd really need to obtain and review the server's Application & System event and HTTPERR logs for the period the server was reporting these errors.
Without these it'd be hard speculate what was the root cause of the problem.
Update:
OP incorrectly tagged his question so this next section no longer applies. However I'll leave in place because I think the information is useful for those encountering these issues and perhaps thinking about migrating to IIS7.x.
You are correct that running two different .NET Framework's in the same application pool can cause these errors but that's something you'd tend to see on Windows 2003/IIS6, not Windows 2008/IIS7.
IIS7 uses a slightly different approach to specifying which .NET Framework version is loaded and it's determined by the Application pool's managedRunTimeVersion property. When requests are processed by IIS/ASP.NET the site's Handler Mapping's use a preCondition attribute to determine when to load the requisite handler (which is kind of like a script mapping in previous versions of IIS).
This mechanism prevents the incorrect runtime version being loaded into the application pool's worker process.
So if an application pool is configured to run .NET Framework version v4.0 only that version will load, even if your application is built against v2.0.
There's a great article on how this works here:
Achtung! IIS7 Preconditions
The section on Handlers about half way through explains why the dangers of accidentally loading the wrong .NET version into a pool are mitigated by the preCondition feature.
A Server Application Unavailable error usually means something catastrophic has happened (like loading the wrong ASP.NET version's ISAPI filter into an already running worker process).
Not closing SQL connections is unlikely to cause this type of serious error. You'd more than likely be seeing a yellow screen of death runtime errors if that were the case. Running out of SQL connections usually doesn't bend ASP.NET so out of shape that the whole service tops itself.
My prime suspect would be a permissions problem where the application pool identity was unable to correctly access the application folders. But it's just a hunch.
Again, what you need to do is get the Application & System event logs and the HTTPERR logs (they reside in %systemroot%\System32\LogFiles\HTTPERR. That will contain clues and facts about what went wrong.
Update 2:
On Windows 2003/IIS6, if you have two applications running different ASP.NET versions that reside in the same pool you will get this error. In my experience (I work for a web hoster) it is the primary cause of this infamous error page:
There's also a tell-tale event logged to the Application Event log:
Event Type: Error
Event Source: ASP.NET 2.0.50727.0
Event Category: None
Event ID: 1062
Date: 12/01/2011
Time: 12:31:43
User: N/A
Computer: KK-DEBUG
Description:
It is not possible to run two different versions of ASP.NET in the same
IIS process. Please use the IIS Administration Tool to reconfigure your
server to run the application in a separate process.
Whilst your root application may not be written in ASP.NET it's likely that something has triggered loading of a different version of the framework into your site's application pool.
there's a rogue web.config in the root...this will trigger ASP.NET to load
there's a wildcard mapping to ASP.NET 1.1 in the site script maps (less likely, but possible)
I'm inclined to think that your new application most certainly ended up in a pool where other sites or applications were running a different framework version. The only way to really find out is to obtain the Application event logs and look for the event shown above.
It's hard to tell; there could be many causes (too many resources used, calling outside of .NET caused something to crash, etc). I would look in the Event log and see if you can find something there.
If you're running different versions of .NET you definitely want separate pools. If you have the option, I would recommend separate pools for each application (even if in the same .NET version).
As far as "closing the connection" (I assume you mean the connection to the database). If you're creating "low level" connections (i.e. SqlConnection, SqlCommand) then make sure you're wrapping them in a "using" statement, otherwise your connection pool can fill up. In my experience though, you should receive regular .NET errors in this case. If you're using an ORM this shouldn't be an issue.
Edit:
If you can't find anything useful in the Event Log, you could try this: http://learn.iis.net/page.aspx/266/troubleshooting-failed-requests-using-tracing-in-iis-7/

Windows Server 2003 IIS Renders ASP.NET 4.0 pages as blank

I have a web project which works fine on my local development machine.
I copied the project to our UAT server, setup a virtual directory pointing to the project and configured it to run on .NET Framework 4.0. I even added the Default.aspx page to the Documents tab. I configured Directory Security to use Windows Authentication.
When i try to access any web page within this application, IIS responds with a blank page. I looked through the event logs and don't see any errors anywhere.
Can someone please help me understand what's going on and how to remedy this?
Thanks in advance!
If you're just seeing a white page with no errors in the event log, it sounds like it could be a problem with the application rather than the hosting environment.
However, there are a few things you could try to doing to troubleshoot this.
Check folder permissions. Try allowing "Everyone" access on your webroot folder and see if that makes any difference.
Confirm that the IIS path is set up correctly but putting a text file in your webroot folder, and then browsing to it and verifying that it's contents are displayed.
Create a basic test.aspx page without any script, just a "Hello World" bit of text, and try browsing to it. Confirm that it displays the correct content.
Edit web.config and turn off custom errors
Try re-registering the ASP.NET extensions with IIS using aspnet_iis (details here)
Hopefully, one of these tests will be able to give you some kind of detailed error message or more insight into the cause of the problem.
For IIS 6.0 on Windows Server 2003, after the install of .NET Framework 4.0, the process of creating Web Sites or Virtual Directories that run under .NET Framework 4.0 is as follows:
Create a new application pool.
Applications running under different
frameworks can't be hosted in the
same application pool, i.e. create
an application pool perf framework.
Next, if you are creating a local
intranet site or virtual directory,
ensure that you don't have "dots" in
the application name. Browsers
confuse the dots to be external web
sites, forcing them to run under
internet zone as appose to the
intranet zone.
Once you create your web site or
virtual directory, make sure that it
runs under an application pool
dedicated for .NET 4.0 applications.
Ensure that when creating your
website or virtual directory, you
click on the ASP.NET tab and select
version 4.0 from the drop down.
Then you may configure as per
normal, with any other additional
settings you may require.
Hope this helps someone experiencing similar issues. Took a while to figure out.

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