How to Troubleshoot Host Connectivity Issues in SCVMM 2008 R2

Note: This article is based on VMM 2008  and might not apply to VMM 2012 (R2)

If you're an administrator for System Center Virtual Machine Manager, at times you may come across cases where a host shows as "Needs Attention" or "Not Responding" or even as "Intermittent connectivity loss to Host".  So how do you go about troubleshooting this type of issue?  Here are a couple tips to get you started:

1. Install the Microsoft Baseline Configuration Analyzer (MBCA) and then scan the problem server with the System Center Virtual Machine Manager 2008 and 2008 R2 Configuration Analyzer (VMMCA).
    a. Run the VMMCA and select "Windows Server-based host" and enter the name of the server experiencing this problem
    b. Upon completion, provide screenshot of report to Microsoft
    c. Install any identified missing hotfixes as directed by the VMMCA.

2. Identify the problem server (managed host).  Is the server currently experiencing the issue?  If so then on the problem server open an elevated command prompt and run the following command:

net stop winrm

Note the time it takes to stop this service.  It should only take a few seconds for the service to stop so anything longer could indicate a problem with winrm being backed up.  If this is the case then you may also notice that the problem can be resolved, albeit temporarily, by a host reboot.  If this is the case then the solution may be to configure the Windows Remote Management service to run in a separate Svchost.exe process. To do this, open an elevated command prompt and run the following commands:

net stop winrm

and then

sc config winrm type= own

Note: there is a space after the "=" in the line above.

If the command completes successfully you should see the following output:

[SC] ChangeServiceConfig SUCCESS

Note: There are occasions in Windows 2008 servers where the Network Location Awareness (NLA) service can become temporarily backed up.  Since NLA shares the same instance of SVCHOST with WinRM, if NLA becomes backed up then WinRM ends up in a waiting state and sometimes does not recover.  To workaround this issue with NLA we can run WinRM in its own instance of SVCHOST which is what the procedure above accomplishes.

3. Another possible cause of this issue can be if a "Restrictive Groups" group policy is removing the VMM server machine account from the local administrators group on the host computer.  This issue is discussed in further detail in KB969164.  If this is the case, move the VMM server and Host computers to a new OU that is blocking inheritance of all group policy objects.

4. Some additional causes of this problem include:
    a. The VMM Agent is not running.
    b. The anti-virus software is scanning ports or protocols