Q. I'm receiving an error about missing DLL files when adding a node to an existing Windows Server 2008 cluster. Why?

A. Certain cluster-aware applications register dynamic link libraries on the cluster nodes to enable specific functionality. When you add additional nodes to a cluster, a check is performed to make sure all registered DLLs exist on the new node. If any are missing, an error is shown.

The node was added successfully, but the 'Host' resourcetype could not be installed on it.Unable to find 'wtclusres.dll' on any of the cluster nodes.The node was added successfully, but the 'WTDisk' resourcetype could not be installed on it.Unable to find 'wtclusres.dll' on any of the cluster nodes.

The problem is that if a resource was moved to this new node of the type displayed in the warning, the required DLL's would be missing, and therefore the resource would fail to function. The solution is to make sure you install the additional software on the new node in the cluster. In my example above, I had installed a cluster-aware iSCSI target on one of the nodes prior to adding the new node.

The error doesn't stop you from adding the node, and other resources that don't require the special DLLs will function with no problems.

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