vSphere Replication, Shadow Copy and backups

[XioWard]

Hello, I'm new to the replication piece and have just implemented vsphere replication on our two sites. I have multiple vm's i would like to replicate, a few being SQL servers. I, also, have a Unitrends UEB setup for our backups. My questions are

1. Will the shadow copy replication interfere with the backups or vice versa?

2. Has anyone had an issue production hanging during the sync with replication?

3. Anything I need to watch out for?

Thanks!

[vbrowncoat]

1. The only way VR would interact with and have the potential to have conflict with backups is if a) you are using a backup tool that utilizes VADP/VM snapshots and b) you have VSS quiescing enabled with VR. Only when you use VSS quiescing does VR take a VM snapshot of a VM. During normal operation VR uses Light-weight Deltas (LWDs) for transferring data and this can't conflict with other VM snapshots. I would recommend only using VSS if your application requires it. Most newer applications will replicate and recover fine without VSS.

2. I have never heard of anything like that. I have heard of problems when using/consolidating large snapshots on busy machines but that is unrelated to VR except when using VSS (which uses VM snapshots).

3. Read the manual, admin guides, etc. Make sure you stay within min/max requirements.

[XioWard]

Thanks for the info. From what I can tell, I want to use VSS for all my Microsoft SQL and Exchange vm's. My backup solution uses VSS to capture the server state and I can see a possible conflict if the replication is large and running at the same time. Is this correct? Am I going to need to specifically change the backup and replication times to work on each vm replicated?

Thanks

[vbrowncoat]

Yes, there is the potential for conflict as they both use VM snapshots and there is no way to coordinate between them. The way that your backup solution handles it will depend on the solution. VR will just retry the  There isn't a way to specify replication times. You can only choose an RPO and VR will do it's best to meet it. This is why I would evaluate if you NEED VSS, especially if you need it for both backups and replication. If you are using a current (SQL 2005 or later, Exchange 2007? or later) application VSS usually isn't required to avoid data corruption.

Does this answer your questions?

[XioWard]

Ok, thanks for the help.

[vbrowncoat]

If you feel my answer was "correct" or "helpful" would you please mark it so?

Thanks!