HowTo monitor the NIC used by a Virtual Machine in a Hyper-V cluster

HowTo monitor the NIC used by a Virtual Machine in a Hyper-V cluster

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Recently I had a customer with the following problem: Hyper-V Host Clusters don't support NIC Teaming. So I have my VM clustered, but my machine does not failover when the NIC used for that machine has a problem. E.g. Network cable unplugged.

One approach to workaround this, is to add a cluster resource script to the Cluster Group. Below is a script, with short instructions.

Please note, this is a sample script, so you should consider testing and modifications to adjust for your own needs. 

Unfortunately, this approach is not applicable if you manage your cluster with SCVMM 2008, as it will mark your VM as "unsupported"

This "unsupporte cluster configuration" notice in SCVMM will go away with SCVMM 2008 R2, and a April updated to SCVMM 2008

Cheers

Robert

 

copy and paste the below and save as NicHa.vbs 

'*******************************************************************************************************************************************************
' Nic HA Script. Sample. Please feedback to robertvi at microsoft.com
'
'INSTALL INSTRUCTIONS
'
' 1. copy this script to all cluster nodes into %windir%\cluster
' 2. In Failover Cluster Management Select the VM you wish to add NIC Monitoring
' 3. Select "Add a resource" -> Generic Script
' 4. Enter %windir%\cluster\nicha.vbs
' 5. Next, Finish. Note the name of the created resource (nicha Script)
' 6. Run ncpa.cpl
' 7. Identfiy the Phyiscl NIC that is used by the Switch for this VM (This NIC should only have the Switch Protocol bound)
'    Usually something like "Local Area Connection"
' 8. Rename this NIC to something like "VM Network 1"
' 9. Do steps 6 to 8 on all cluster nodes
' 10. Open a Elevated CMD Prompt
' 11. Using the names from above, "nicha script", "VM Network 1"'
' 12. In cmd prompt, issue the following command: cluster res "nicha Script" /priv NicName="VM Network 1"
' 13. Online the Script Resource
'
'You may edit the properties of the Virtual Machine Group in Failover Cluster Management to allow more failovers in a given period.
'The Default of 2 may be reached easily during testing. The script resource will then fail, but the group will not move
'
'The availability of the NIC is checked every minute by default.
'This could be changed in the Advanced Properties of the Script Resource in the "Thorough resource health check interval", if needed
'
'
'
'*******************************************************************************************************************************************************


'*******************************************************************************************************************************************************


'*******************************************************************************************************************************************************
'Global variables
'*******************************************************************************************************************************************************
'Script Version
ScriptVersion = "0.2"


'*******************************************************************************************************************************************************
'Open()
'
'*******************************************************************************************************************************************************
Function Open()
   
 On Error Resume Next
 Resource.LogInformation("Entering Open() for NIC Monitoring Generic Script Version " & ScriptVersion)

 If Resource.PropertyExists("NicName") = FALSE Then
  Resource.AddProperty("NicName")
  Resource.LogInformation("NICHA: Property NicName not configured")
 End If


Open = 0

End Function


'*******************************************************************************************************************************************************
'Online()
'
 
'*******************************************************************************************************************************************************
Function Online()

 'Check if the NIC is connected, otherwise fail Open

 Online = 1

 strComputer = "."
 strNicName = Resource.NicName
 strquery = "Select * from Win32_NetworkAdapter where NetConnectionID = '" & strNicName & "'"


 Set objWMIService = GetObject("winmgmts:" _
  & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")

 Set colItems = objWMIService.ExecQuery(strquery)

 if colItems.Count = 0 then
  Resource.LogInformation("NICHA: Error - NIC not found")
  set objWMIService = nothing
  Set colItems = nothing
  Exit Function
 end if

 set objItem = colItems.ItemIndex(0)


 if objItem.NetConnectionStatus = 2 then
  Online = 0
 else
   Resource.LogInformation("NICHA: Error - NIC not in connected state")

 end if


 set objWMIService = nothing
 Set colItems = nothing
 set objItem = nothing


End Function


'*******************************************************************************************************************************************************
'LooksAlive()
'
'Return success
'*******************************************************************************************************************************************************
Function LooksAlive()
 On Error Resume Next
 LooksAlive = TRUE
End Function


'*******************************************************************************************************************************************************
'IsAlive()
'
'*******************************************************************************************************************************************************
Function IsAlive()
   
 On Error Resume Next
 IsAlive = FALSE

 strComputer = "."
 strNicName = Resource.NicName
 strquery = "Select * from Win32_NetworkAdapter where NetConnectionID = '" & strNicName & "'"


 Set objWMIService = GetObject("winmgmts:" _
  & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")

 Set colItems = objWMIService.ExecQuery(strquery)

 if colItems.Count = 0 then
  Resource.LogInformation("NICHA: Error - NIC not found")
  set objWMIService = nothing
  Set colItems = nothing
  Exit Function
 end if

 set objItem = colItems.ItemIndex(0)


 if objItem.NetConnectionStatus = 2 then
  IsAlive = TRUE
 else
   Resource.LogInformation("NICHA: Error - NIC not in connected state")

 end if


 set objWMIService = nothing
 Set colItems = nothing
 set objItem = nothing


End Function


'*******************************************************************************************************************************************************
'Offline()
'
'*******************************************************************************************************************************************************
Function Offline()

 On Error Resume Next
 Offline = 0

End Function


'*******************************************************************************************************************************************************
'Terminate()
'
'*******************************************************************************************************************************************************
Function Terminate()

 On Error Resume Next
 Terminate = 0


End Function

'*******************************************************************************************************************************************************
'Close()
'
'Return success
'*******************************************************************************************************************************************************
Function Close()
 Close = 0
End Function

 

 

  • Hi Cluster Fans, Resources can be hard to find, so every few months we will be publishing an updated

  • Thank you for sharing this script.

    A few days ago, we could resolve the problem from this post.

  • I tried the script and it works. Thank you Sir. However, i have a small problem. First, I have a 2-node failover cluster on windows server 2008 R2. When i disconnect the NIC used by the VM which is running on node 1, the failover is activated and I have a successful migration. Now the VM is running on node 2. But when I disconnect the NIC of the VM running on node 2 it fails to migrate. Any ideas please ?

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