2013-04-16 12:13 PM
Hi! New to NetApp and I have a couple of questions as I am looking at the product from a design perspective.
I have a scenario. I would like to replicate a vol which is on filer A to filer B, but I want to make sure the of the data integrity. Say the data on this volume was some MS SQL databases and I chose not to use database replication, but wanted to use replication at the array level.
Couple of questions if I may?
Many thanks for helping if you can as I am sure this question comes up time and time again!
Solved! SEE THE SOLUTION
2013-04-16 10:59 PM
1. It is possible to use one HA pair (MetroCluster) or independent filers with replication (SnapMirror). Exact choice depends on multiple factors.
2. Yes, but you lose most fault tolerance features.
3. Asynchronous replication in NetApp works with snapshots and it is guaranteed that you see either old or new state atomically. If all data is located on a single volume, snapshot is crash-consistent by definition. For multiple volumes you probably need application assistance to get consistent snapshots or use consistency groups.
4. SnapMirror works both synchronously and asynchronously. SnapMirror Sync ships data continuously, SnapMirror Async - based on schedule. Minimum time is 1 minute although it is not really recommended.
6. SnapVault is backup tool. DR tool is SnapMirror.
2013-04-17 02:59 AM
Thanks for your response. Just one last question
After doing some more reading, I see there is a product called SyncMirror. Does that give me real time synchronization, rather than snapshots? Or is it in fact just an extension of SnapMirror?
Yes, I meant to say backup tool. Thanks for the clarification.
2013-04-17 03:07 AM
SyncMirror is mirroring between aggregates inside one head. MetroCluster is using it to mirror data between sites. Yes, it is real time synchronization. No, it is unrelated to SnapMirror.
2013-04-17 01:57 PM
Great - many thanks. You have helped clear a few things up. I will say, after playing with NetApp and looking at the design considerations, it reminds me of SAN Symphony. It has similar functionality but WAFL seems to be the big difference and the way the
inode trees work. I especially like the way snapshots just copy the root inode and remap branches to any new blocks. That is great.
Thanks for your help on this,