As I understand it, when the block level transfer of the blocks that changed between last transfer and the time the new snapshot was taken on source is completed, Netapp makes this just transferred snapshot on the target the active file system and removes previous snapshot from the source - the target at that point is synchronized with the source at the time of the last snapshot.
When the snapshot on target volume becomes the active file system, what happens to files that reside on data blocks that changed in case these files happen to be locked by clients?
Does the question make sense?
If it does not make any sense, let me try to ask it differently... Unlike typical NFS, when CIFS clients read the file, the file is actually locked until read operation completes. In other words, other processes cannot update the file while the file is being read. What happens in case of Netapp if CIFS clients read the file from the snapmirrored volume and the snapmirror transfer completes *while* the file is being read?
thanks again, Mark
As I understand it, file locking only pertains to files in the active filesystem. File locks do not exist in snapshots. When you run snapmirror, the source volume is snapshotted first and the snapshot is the input to snapmirror. CIFS clients can continue to read, write, and lock files in the active filesystem without interfering with snapmirror, because snapmirror uses a snapshot instead of the active filesystem.
Steve Losen scl@virginia.edu phone: 434-924-0640
University of Virginia ITC Unix Support