Tag Archives: 2012

Tech Stuff

Windows Server 2012: Cluster Aware Updating

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In my continued efforts over the past few weeks putting together a Windows Server 2012 Hyper-V Cluster, I recently discovered a nifty new feature to Windows Server 2012’s Failover Clustering – Cluster Aware Updating.

This feature is going to save a lot of SysAdmin time when it comes to patching your Failover Cluster nodes, the only real interaction required is simply to setup the schedule. Cluster Aware Updating will fully automate patching your cluster nodes one-by-one without impact to your cluster applications or roles.

Initial setup of CAU requires that you select a “Co-ordinator”, and this basically does what it says on the tin. The Co-ordinator manages and monitors the patching tasks across the nodes in the cluster. This role can be enabled within the cluster or outside.

The CAU Co-ordinator will perform the following steps -:

  • Download Updates to each node
  • Selects the node with the fewest applications/roles first (although you can specify a specific order during setup)
  • Initiates a Node Drain, i.e. moves the applications/roles off the node to other nodes in the cluster
  • Sets the node into Maintenance Mode
  • Installs the downloaded updates
  • Restarts the node if required
  • Verifies the installed updates
  • Brings the node out of Maintenance Mode
  • Moves the applications/roles that were previously moved off the node back again
  • Repeat the above steps for the next node in the cluster

As you can see performing those steps manually is a very time consuming task, especially for large clusters with many applications/roles. The most time consuming and tedious part being the application/role migrations and ensuring you move the same roles back again afterwards.

CAU can install updates from a number of sources including:

  • Windows/Microsoft Update
  • Windows Server Update Services (WSUS)
  • Hotfixes or Cumulative Updates not released via Windows/MS Update (setup a file share)
  • 3rd Party Driver and Firmware updates (setup file share)

So not only does CAU save you time but it ensures that your cluster nodes are all at the same update levels too which of course is desirable at all times.

One thing I did notice was the SCOM agent on the cluster nodes got stuck in Maintenance Mode. I had to fix this by putting the nodes into Maintenance Mode via the SCOM console for 10 minutes, after which the nodes were successfully monitored again.

This is certainly one of my favourite additions to the Server 2012 feature set so far. If you have a Server 2012 cluster then enable this feature!

 

James

Tech Stuff

SCOM 2012: Monitor Overrides for mixed Hyper-V 2008/2012 Environments

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If you have an environment containing both Hyper-V 2008 and 2012 servers and thus have the Hyper-V 2008 Management Packs installed you’ll find you get some false alerts for your 2012 Hyper-V servers.

The 2008 Hyper-V Management pack looks for event logs that no longer exist in Hyper-V 2012 thus you’ll receive an alert stating an event log is inaccessible.

Example SCOM Alerts:

Alert description: The Windows Event Log Provider is still unable to open the Microsoft-Windows-Hyper-V-Network-Admin event log on computer ‘hostname’. The Provider has been unable to open the Microsoft-Windows-Hyper-V-Network-Admin event log for 720 seconds.

Alert description: The Windows Event Log Provider is still unable to open the Microsoft-Windows-Hyper-V-Image-Management-Service-Admin event log on computer ‘hostname’.
The Provider has been unable to open the Microsoft-Windows-Hyper-V-Image-Management-Service-Admin event log for 6480 seconds.

To resolve this you need to create an override that excludes your Hyper-V 2012 hosts from these monitors as follows:

  1. In the SCOM Management console navigate to Authoring > Management Pack Objects > Monitors
  2. Click Scope button at the top of the console, enter ‘Hyper-V’ > View All Targets > Select All > OK
  3. In the Look for field enter ‘Connectivity’ > Find
  4. For both ‘Port Connectivity’ and ‘Port Disconnectivity’ right click the Monitor > Overrides > Disable the monitor > For a specific object of class
  5. You should see your Agent managed Hyper-V hosts, tick the 2012 Hyper-V Hosts > OK
  6. Back to the Look for field enter ‘mounted drive’ > Find
  7. Find the ‘Mounted Drive Read-Only’ monitor > Right click > Overrides > Disable the monitor > For a specific object of class
  8. Select your 2012 Hyper-V hosts > OK

I found the alerts didn’t recover automatically after adding the overrides and had to manually mark them as resolved/closed.

 

James

 

Tech Stuff

SCOM 2012 SP1: Broken Alert Link URL

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I’ve been working on a System Center Operations Manager (SCOM) 2012 deployment recently. Now that Microsoft have made Service Pack 1 fully available it appears the normal Alert URL is somewhat broken.

The original Alert URL looks something like this: http://scomwebserver/OperationsManager/default.aspx?DisplayMode=Pivot&ViewType=AlertView&AlertID=$UrlEncodeData/Context/DataItem/AlertId$
However since the installation of Service Pack 1 the Alert View never actually completes loading.

The workaround for the time being is to update the Alert URL in your Channel Notification to: http://scomwebserver/MonitoringView/default.aspx?DisplayMode=Pivot&ViewType=AlertView&AlertID=$UrlEncodeData/Context/DataItem/AlertId$
This works, but you must first authenticate at the /OperationsManager URL first as it appears that authentication fails if you browse to the MonitoringView without having visited the OperationsManager URL first!

A pretty irritating problem, hopefully it won’t take long for MS to release a fix. Cumulative Update 1 for SP1 was released pretty quickly after the release of SP1.
I’ll post an update once a fix has been released.

James