We have a .net web application that is running in IIS7.5 on an application pool that is set to run with a domain level AD account instead of the default account.
It has been configured according to these instructions:
http://support.microsoft.com/kb/813834
to use
myProxy.Credentials = System.Net.CredentialCache.DefaultCredentials;
so that the credentials the pool is running on are passed to the web service.
This works in my test VM (which may have had other settings modified in the past)
Deployed on our Dev Server, the same code does not work.
I know the Web Service isn't the culprit because the IIS log shows no Account info passed to the webservice call, but if I point my test VM to the webservice on the server it works and does.
Is there a configuration/permission thing I'm missing somewhere?
Any pointers?
Edit: Learned some more. Event Viewer is showing audit failures with NULL SID for this account, even though from the VM the SID comes through correctly.
Thanks!
Got it! So the NULL SID led me to the right place:
This is because of a "working as designed" feature with windows.
read was MS has to say about it here:
http://support.microsoft.com/kb/896861
Registry change option #1 fixed it.
Related
I have an MVC4 application hosted on IIS in my local system. The application provides the search capabilities by using various Searchblox API. I have stored the host server value in my web.config. Now while my application is running and I change my host value say from "https://xyz" to "https://abc" in my config then for some places the correct value is fetched but for one call the old "https://xyz" is fetched.
I perform the below steps in sequence:-
Hit my application page from IE.
App executes successfully.
Open Web.config in VS to switch the host value.
Save the config file. (Now as per my knowledge this should have restarted the appdomian consisting my app and should have brought the new value)
Hit my application again in IE.
Watch the internal calls in Fiddler. All API calls are now made to new "https://abc" but one call is made to "https://xyz".
This behavior works fine if I recycle the Apppool containing my application.
Someone, please explain why this might be happening and how can I make sure that my application always pick the new values for every call?
This was happening because we were caching the previous host value in order to use it if the new changed host API fails to establish a connection. This was completely app specific.
First of all, we have a MVC web application which uses NHibernate (version 3) and an Oracle 11g database.
The application is working, but when we publish in the production server a curious scenario happens:
The user access the application and perform a task, for example, select a link into the Menu.
The user waits a couple of minutes (2-3 minutes).
The user perform another task, for example, reload the same page or select another link into the Menu.
The application fails with a ORA-12571: TNS:packet writer failure exception.
The user just refresh the error page, the application works.
The first thing we tried to do was to isolate the problem, so we published the application into another server with the exactly same configuration:
Same binaries, of course.
Same Oracle x64 client version, even the minor version.
Same Windows Server 2008 version with IIS 7.5.
Same IIS configuration (we compared the windows/system32/inetsrv/config files using WinMerge).
Accessing the same production database.
And for our surprise we couldn't reproduce the problem.
Please, someone have a clue of what is going on?
The problem is related to the connection pool of the server's oracle client. It seems that it is delivering invalid connections to the web application, while in the other servers it does not happens.
The solution is not very interesting, but putting the Validate Connection = True inside the connection string resolved the issue. I am aware of the performance penalty of this, but I am out of options.
PS: using this flag, each connection is validated by the connection pool service before delivering it for the client application. This is not very nice, since a database round-trip will happen for every connection request.
I have a asp.net website that is deployed on two servers. In front of the servers there's a load balancer that distribute requests to the two servers. To store the session we use SQL Server.
My problem is that if the user go to the page, press a button and then by the load balancer happens to be routed to the other server that request wont be recognized as a postback? Why is that, shouldn't it work just fine even with postbacks as long as the servers share the same machine keys?
Details:
Both servers have the same machine key configured, and I verified that the actual session is the same on both servers by a small debug page I made that sets and prints out a session object.
To further verify the keys and Id I printed out the values of HttpRuntime.AppDomainAppId and a hashed machinekey (MachineKeySection)ConfigurationManager.GetSection("system.web/machineKey") and the sessionId Session.SessionID and got the same output on both servers. I used Session Debug page as a base for this. Its output looks something like this (I replaced my actual machinkey hash and session id with dummy values):
Current DataTime: 2012-07-20 10:52:58
Current Session Mode: SQLServer
HttpRuntime.AppDomainAppId: /LM/W3SVC/5/ROOT
Hashed with the MachineKey: HjtOPW5dfoihdlkd+SdsfkEWfs0=
Local Machine Name: 127.0.0.1
Current Session ID: 2alsudhsdkjlhcmnsdfkhsdf
The ID for the site, found in IISMgr under Advanced Settings on the site is the same on all servers.
As long as I stay on the same server everything works as expected.
When I run the page locally (first request to web farm, then route second button click to localhost by fiddler), I get the same behaviour
Stepping through the code and reading up on the IsPostBack property it seems my problem is that this._fPageLayoutChanged on the Page is true. However, if I understand things correctly it should be false when a postback happens? SO Question on its implementation
Both servers run IIS 7.
Both servers run Windows Server Web with SP2 and the same windows update updates installed. My local dev machine on the other hand runs Windows 7.
Turns out that adding a manual entry of the Machinekey in the web.config fixed the problem. Very strange as I checked its global value and also the hash as detailed in the question but now it works.
I take that back. After our last release the problem is back, so the machinekey addition did not help at all.
(This is a question about a vague problem. I try to present all relevant data, in the hope that someone has helpful information; apologies for the long description.)
Our web app
We have a .NET 4 web application running in IIS 7.5 accessing Active Directory and a SQL Server database.
This web application is running under a virtual 'app pool identity', by setting the Identity of the application's application pool to ApplicationPoolIdentity. A concise description of virtual identities can be found in a StackOverflow answer, and the blog post to which it refers: an app pool identity is just an additional group which is added to the web application's worker processes which is running as 'network service'. However, one source vaguely suggests that "Network Service and ApplicationPoolIdentity do have differences that IIS.net site documents do not publish." So a virtual identity might be more than just an additional group.
We chose to use ApplicationPoolIdentity, as opposed to NetworkService, because it became the default in IIS 7.5 (see, e.g., here), and per Microsoft's recommendation: "This identity allows administrators to specify permissions that pertain only to the identity under which the application pool is running, thereby increasing server security." (from processModel Element for add for applicationPools [IIS 7 Settings Schema]) "Application Pool Identities are a powerful new isolation feature" which "make running IIS applications even more secure and reliable. " (from IIS.net article "Application Pool Identities")
The application uses Integrated Windows Authentication, but with <identity impersonate="false"/>, so that not the end user's identity but the virtual app pool identity is used to run our code.
This application queries Active Directory using the System.DirectoryServices classes, i.e., the ADSI API. In most places this is done without specifying an additional username/password or other credentials.
This application also connects to a SQL Server database using Integrated Security=true in the connection string. If the database is local, then we see that IIS APPPOOL\OurAppPoolName is used to connect to the database; if the database is remote, then the machine account OURDOMAIN\ourwebserver$ is used.
Our problems
We regularly have issues where a working installation starts to fail in one of the following ways.
When the database is on a remote system, then the database connection starts to fail: "Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON'. Reason: Token-based server access validation failed with an infrastructure error. Check for previous errors." The previous error is "Error: 18456, Severity: 14, State: 11." So it seems that now OURDOMAIN\ourwebserver$ is not used anymore, but instead anonymous access is attempted. (We have anecdotal evidence that this problem occurred when UAC was switched off, and that it went away after switching on UAC. But note that changing UAC requires a reboot...) A similar problem is reported in IIS.net thread "use ApplicationPoolIdentity to connect to SQL", specifically in one reply.
Active Directory operations through ADSI (System.DirectoryServices) start to fail with error 0x8000500C ("Unknown Error"), 0x80072020 ("An operations error occurred."), or 0x200B ("The specified directory service attribute or value does not exist").
Signing in to the application from Internet Explorer starts to fail, with HTTP 401 errors. But if in IIS we then put NTLM before Negotiate then it works again. (Note that access to AD is needed for Kerberos but not for NTLM.) A similar problem is reported in IIS.net thread "Window Authentication Failing with AppPool Identity".
Our hypothesis and workaround
At least the AD and sign-in problems always seem to go away when switching the application pool from ApplicationPoolIdentity to NetworkService. (We found one report confirming this.)
Page "Troubleshooting Authentication Problems on ASP Pages" has some suggestions related to primary vs. secondary tokens, and what I find encouraging is that it links the first two of our errors: it mentions NT AUTHORITY\ANONYMOUS LOGON access, and AD errors 0x8000500C and "The specified directory service attribute or value does not exist".
(The same page also mentions ADSI schema cache problems, but everything we can find on that topic is old. For now we consider this to be unrelated.)
Based on the above, our current working hypothesis is that, only when running under a virtual app pool identity, our web application (IIS? worker process?) suddenly loses its primary token, so that IIS only has a secondary token, so that all access to Active Directory and SQL Server is done anonymously, leading to all of the above errors.
For now we intend to switch from ApplicationPoolIdentity to NetworkService. Hopefully this makes all of the above problems go away. But we are not sure; and we would like to switch back if possible.
Our question
Is the above hypothesis correct, and if so, is this a bug in IIS/Windows/.NET? Under which circumstances does this primary token loss occur?
Through Microsoft Support I found out that we ran into the issue described in Microsoft Knowledge Base article KB2545850. This only occurs when ApplicationPoolIdentity is used. It occurs very easily, namely, after the machine account password is changed (which by default happens automatically every 30 days), and then IIS is restarted (e.g., through iisreset). Note that the problem goes away after a reboot, according to Microsoft and our observations.
According to Microsoft it is not possible to check if your Windows/IIS has gotten into this state.
Microsoft has a hotfix attached to this KB article. There is no indication when that hotfix will be rolled into an official delivery, and the hotfix is already 10 months old. In our specific case, we decided to switch to NetworkService instead.
See https://serverfault.com/a/403534/126432 for my comments on the same problem/solution.
Using the hotfix you linked to allowed me to get ApplicationPoolIdentity working as the docs say it should. This hotfix doesn't specifically describe a solution for accessing network resources as NT AUTHORITY\ANONYMOUS LOGON, but it's related to the computer password changing. Bottom line is that it worked for me, at least so far.
This is also relevant for Umbraco using Active Directory authentication.
From time-to-time you may get this exception:
Configuration Error
The specified directory service attribute or value does not exist
This is apparently caused by the problem outlined here. A reboot invariably fixes it.
The setup: 2 web servers and a seperate state server
I have two production web servers in a load balanced configuration. The ASP.NET web app they host shares state (like a web farm) using this line in their web.configs:
<sessionState mode="StateServer" stateConnectionString="tcpip=9.9.9.9:42424" cookieless="false" timeout="60"/>
9.9.9.9 is the IP of the machine the asp.net session state service is running on (ok it's not 9.9.9.9 really, changed to protect the innocent). It's a third machine (the database server, actually.
It worked fine until...
The error: website down!
Suddenly the site went down, just showing a generic asp.net error page ('turn custom errors off to see this error' or whatever).
The app's log recorded the actual error message:
An unhandled exception occurred Unable to make the session state request to the session state server. Please ensure that the ASP.NET State service is started and that the client and server ports are the same. If the server is on a remote machine, please ensure that it accepts remote requests by checking the value of HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\aspnet_state\Parameters\AllowRemoteConnection. If the server is on the local machine, and if the before mentioned registry value does not exist or is set to 0, then the state server connection string must use either 'localhost' or '127.0.0.1' as the server name.
So it appears that the web app was unable to contact the state server (9.9.9.9).
I "tried turning if auf and then onnegen" - restarting the state server fixed the problem.
Why?
I really want know what happened and why so I can prevent it happening again.
So far all I have are two theories:
A windows update, to .net framework 4, was applied around that time on the state server. So maybe the update did something to the asp.net state service? The windows event viewer showed that .net 4 had logged a warning around then:
Updates to the IIS metabase were aborted because IIS is either not installed or is disabled on this machine. To configure ASP.NET to run in IIS, please install or enable IIS and re-register ASP.NET using aspnet_regiis.exe /i.
Some kind of temporary network problem between the prod web sites and the state server? They do sit right next to each other in the same physical rack though.
??? Any other ideas, anyone?
Anyone seen this before, or able to correct me on anything?
Has this happened since? The easy answer is that the problem was with the db server, not the web app. Are there any relevant errors in the log on the db server?
The fact that both apps threw an error indicates that a common resource was the problem. We chased a similar issue for a good solid week awhile back, and eventually found a faulty fiber channel gadget. (that's below my OSI level, not sure about the details).
Start–> Administrative Tools –> Services
Right-click over the ASP.NET State Service and click “start”
It is working fine We need to follow the steps
Had a similar issue before when our Infrastructure team tried sneaking in an install of 3.5 when they forgot to install it on our Production box. Not bouncing a server after a framework update is just going to cause all kinds of weird problems.