Notes from the field: uberAgent to the rescue!!

We all know it, the once in a while “it’s slow logging  on..” and then it gets dropped at the escalation desk for a resolution. So I got the call for troubleshooting this issue. Since I knew from previous experiences that uberAgent is the troubleshooting tool you will want for this I contacted them and requested the consulting license at https://uberagent.com/ (thanks to Helge Klein) did the installation of Splunk / Uberagent and got myself a monitoring baseline to work with. A little background on the setup:

  • vSphere 6.0
  • XenDesktop 7.15 / MCS – Windows 8.1 & Windows Server 2012 R2
  • RES WorkspaceManager 10.1.300.1

The problem was at times users would have a profile initialization of 90 seconds! and at times the user shell would hang..

After a period of two weeks I would have my baseline with uberAgent and filtered out that this would be random very early start of the day or just after break time. No funny business whatsoever in the environment and no lack of resources e.g. iops or cpu/memory exhaustion, drilling down in some user trending with uberAgent I came to a somewhat recurring user base that experienced the issue. Ok! That helps and after that I could reproduce it with the useraccounts in question displaying the following screen:Dropped this in the resrockstars.slack.com group and got a quick reply from Dennis van Dam in regards to traceviewer and came to the following:This in turn pointed me out to the following support article:Problem resolved and a happy customer! Hope this helps you out as well.

Reference article:

HOWTO: Create a trace file

Notes from the lab: Exchange Server 2016 CU6 broken by default??

I came across the most peculiar issue I’ve seen so far with Exchange 2016.
Installed a greenfield setup and the ECP/OWA page was broken by default with the following entry in event viewer:
——————————————————————————————————————————————————–
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 9-9-2017 22:26:57
Event time (UTC): 9-9-2017 20:26:57
Event ID: 53b3f1166cb147408cb97bc79483c3f5
Event sequence: 2
Event occurrence: 1
Event detail code: 0

Application information:
Application domain: /LM/W3SVC/2/ROOT/owa-4-131494624100042355
Trust level: Full
Application Virtual Path: /owa
Application Path: C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\owa\
Machine name: EX01

Process information:
Process ID: 7756
Process name: w3wp.exe
Account name: NT AUTHORITY\SYSTEM

Exception information:
Exception type: TargetInvocationException
Exception message: Exception has been thrown by the target of an invocation.
at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at Owin.Loader.DefaultLoader.<>c__DisplayClass12.<MakeDelegate>b__b(IAppBuilder builder)
at Owin.Loader.DefaultLoader.<>c__DisplayClass1.<LoadImplementation>b__0(IAppBuilder builder)
at Microsoft.Owin.Host.SystemWeb.OwinAppContext.Initialize(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinBuilder.Build(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.InitializeBlueprint()
at System.Threading.LazyInitializer.EnsureInitializedCore[T](T& target, Boolean& initialized, Object& syncLock, Func`1 valueFactory)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.Init(HttpApplication context)
at System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers)
at System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context)
at System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context)
at System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext)

Encryption certificate is absent
at Microsoft.Exchange.Security.Authentication.Utility.GetCertificates()
at Microsoft.Exchange.Clients.Owa2.Server.Core.notifications.SignalR.SignalRStartup.Configuration(IAppBuilder app)

Request information:
Request URL: https://localhost:444/owa/exhealth.check
Request path: /owa/exhealth.check
User host address: 127.0.0.1
User:
Is authenticated: False
Authentication Type:
Thread account name: NT AUTHORITY\SYSTEM

Thread information:
Thread ID: 25
Thread account name: NT AUTHORITY\SYSTEM
Is impersonating: False
Stack trace: at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at Owin.Loader.DefaultLoader.<>c__DisplayClass12.<MakeDelegate>b__b(IAppBuilder builder)
at Owin.Loader.DefaultLoader.<>c__DisplayClass1.<LoadImplementation>b__0(IAppBuilder builder)
at Microsoft.Owin.Host.SystemWeb.OwinAppContext.Initialize(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinBuilder.Build(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.InitializeBlueprint()
at System.Threading.LazyInitializer.EnsureInitializedCore[T](T& target, Boolean& initialized, Object& syncLock, Func`1 valueFactory)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.Init(HttpApplication context)
at System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers)
at System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context)
at System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context)
at System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext)

Custom event details:
———————————————————————————————————————————————————
After some digging I came across this blog: https://justaucguy.wordpress.com/2014/12/01/exchange-2013-cu6-owa-something-went-wrong/ and https://blogs.technet.microsoft.com/rmilne/2017/06/27/exchange-2016-cu6-released/
the first one mentions of replacing the sharedwebconfig, which wasn’t my error but tried it anyway without any change, and the other triggered me with certificates… okay I checked them via the Exchange Management Shell and also there no issues..

Finally I got the bugger in IIS, it appears that a wrong certificate got bound at installation (yeah two clean servers and even some re-runs in other lab setups give me the same) but the solution was to unbound the certificate it had and bind the Microsoft Exchange Server Auth Certificate and do a IISreset.

Problem was instantly solved in my case. (the second blog above mentions that in an upgrade scenario the Microsoft Exchange Auth Certificate could get deleted so beware!!)

See the following reference regarding the binding in IIS:

Hope this helps!

 

Notes from the lab: Windows Server 2016 and MDT gen2 secure boot

For some upcoming projects and also lab use cases I’ve decided to brush up on some MDT/Automation tasks.

For this I’ve deployed a new Windows Server 2016 Hyper-V VirtualMachine Gen2 with secure boot enabled and installed MDT server and configured it to an up and running environment(yeah.. right).

At first I thought there were some inconsistencies with the installer because I kept getting an error on the windows overlay filter driver and it’s signature, didn’t pay much attention and kept going configured the MDT Deployment share and everything with it. Clicked on the update share item and…. boom kept getting an error on unable to mount the wim file of winpe and well a broken MDT setup..

Did some searching and came across the following articles: https://blogs.technet.microsoft.com/configurationmgr/2017/04/14/known-issue-with-the-windows-adk-for-windows-10-version-1703/ and https://blogs.technet.microsoft.com/mniehaus/2017/05/16/quick-workaround-for-adk-1703-issue/

My solution for now was to disable secure boot (because it’s an lab environment) but hope it gets resolved by Microsoft in an upcoming update, imho these workarounds shouldn’t be necessary.