Dell Unity: Async Replication Destination File System or NFS Datastore Goes Offline
Summary: On Dell Unity OE 4.2.0 and later, an asynchronously replicated File System or NFS Datastore at the destination may go offline due to a known issue involving file system shrink operations and snapshot replication. Recovery requires assistance from Dell Technical Support or the Recovery Team, and the issue is resolved in Dell Unity OE 4.5 and later. ...
Symptoms
On Dell Unity arrays, an asynchronously replicated File System or NFS Datastore at the destination site may unexpectedly go offline.
This issue can occur after a small snapshot is replicated and the destination file system undergoes a shrink operation, resulting in a reduction of the underlying virtual unit (VU) size. During replication of a subsequent snapshot, validation of I/O associated with the common base snapshot may fail if its log extends beyond the new, reduced VU size. As a result, the replication operation fails and the destination file system is taken offline.
Cause
This is a known issue affecting Dell Unity OE 4.2.0 and later releases.
Resolution
To recover the affected File System or NFS Datastore, contact Dell Technical Support or your Authorized Service Representative and reference Knowledge Base article 000055346.
A member of the Recovery Team must first recover the affected File System or NFS Datastore.
After recovery, upgrade the system to Dell Unity OE 4.5 or later, where this issue has been resolved.