DFS Replication will sometimes give the following error in the event log:
The DFS Replication service encountered an error communicating with partner CSL-VMHOST-001 for replication group Domain System Volume.
The event source is DFSR and the Event ID is 5002.
Typically this is caused by a replication partner going down. Most often this is due to someone performing Windows Updates on the server and it’s safe to ignore the error (after testing replication still works).