It’s IsAlive! Wait, where did my cluster go?

by Christopher Kusek (PKGuild) Baltimization, Christopher Kusek, Exchange, Hyper-V, Informational, Microsoft, SQL, Storage, Technology, Windows Server

It’s a dark night, you’re in a cold murky alley.   There’s a random file found in the root of your drive (or mount point).   Suddenly, your cluster goes offline.   WTF!

If you’re thinking, “Damnit, what did my storage vendor do now!” You’d be mistaken.

There’s this little doozy out there:

“A physical disk resource may unexpectedly fail or go offline when the IsAlive function is executed on a Windows Server 2008 cluster node” to the tune of Q953652

Microsoft declares it to happen when you meet the following scenario:

  • You have a Windows Server 2008 cluster node.
  • The IsAlive function is executed on the cluster node while a file is being accessed in the root folder of the cluster disk.

In this scenario, a physical disk resource on the Windows Server 2008 cluster node may unexpectedly fail or go offline. This behavior occurs randomly.

Or otherwise read as: If you have a file in the root of Drive letter or Mount point, the drive may ‘disappear’ when you have this configured in a cluster (This does not apply to Server 2008 single servers)

Quite often this is blamed on the storage (regardless of vendor) so be sure to keep your clusters up to spec and make sure to apply this Hotfix from Microsoft, especially if you meet this criteria!

Good luck Clusters, and those cold dark alleys won’t be so bad.