In the technet article for Cluster Aware Updating best practices, it states "All cluster nodes should be uniformly configured to use the same update source, for example, a WSUS server, Windows Update, or Microsoft Update."
Technet - Requirements and Best Practices for Cluster-Aware Updating
This language is a bit ambiguous. If I am using WSUS servers, should the nodes have their update source set to the same WSUS server?
Or is using a different WSUS server acceptable for different nodes, and the documentation is simply stating that the same type of update source (WSUS or Windows Update) should be the same across all nodes?
Scenario: I have clusters that are stretched across two datacenters for disaster recovery purposes. Each datacenter has its own WSUS server, one being configured as a downstream of the other. Nodes in the cluster will be configured to pull from the WSUS server located in the same datacenter. I would like to use cluster aware updating to patch these clusters. All servers are Windows 2012 R2 running in a domain at Windows 2012 R2 functional level.
That's not a requirement. The article mentions it as a best practice because it's important to have the same patch level across all of your nodes to avoid incompatibilities and surprises.
If your WSUS servers are synced, it shouldn't be a problem.