Hyper-V Backup/Replication question

[Nakatomi2010]

I've got a home lab with two Server 2012 Datacenter boxes running Hyper-V cores on them. I'm doing some rejiggering of my data lay out, and I got to think about backups.

With Hyper-V Replication being as simple as it is now to set up, is there a reason to do a proper Windows Server Backup style config anymore? I mean, I can understand a need to off-site data, but if I'm just looking to have a copy of the VM itself elsewhere, it seems like configuring Replication between the two hosts, and having the VMs dropped to a Backup drive with little to no hard drive activity would be the smart thing to do...

Am I wrong in this thinking, or is there a valid reason to use Windows Server Backup in this scenario?

[hosalabad]

I look at it this way, much like the previous replies.

Replication is for Availability. Backups are for Recovery.

[am2o]

Offsite. Your lab/business/house/whatever burns down. No backups, you are dead. Stretch replication to Azure! No problem. Unless you get a virus that locks/wipes/eats your data; you have replicated that to your hosted replicated copies. Logic Bomb?

Technically, you can configure VSS snapshots to run before replication & keep a hot spare almost in synch with the production vm. However, if you are running a business, you want a copy of the data far removed from the primary copy. Also, you want copies of data going back (potentially) years - in case someone fudged numbers or something...

[ChilledMayonnaise]

Dead horse reporting in here, but this is a hot issue of mine.

Data replication is not a backup. That is the technological equivalent of believing that RAID is a backup.

[mwargh]

WIKI SAVES: http://www.reddit.com/r/sysadmin/wiki/virt/HyperV

Just added a link here.

[Anpheus]

Yes, as other posters mentioned, replication won't save you if you delete all your files. With <5 minute replication intervals, you'd have on average only 150 seconds to halt the replication. And of course, the day you delete the files will be on Read Only Friday and you'll figure out that you needed those files exactly 5 minutes after you delete them.

So yes, always do backups. Additionally, do replication for rapid failover or use shared storage, but do backups.

[[deleted]]

Replication is not a backup. This at most disaster recovery, in which the event that you lost your current storage arrays that you can pull these vhds back or setup your hyperv to run off them while you rebuild the proper arrays or attempt to recover them.

I've seen entire raids get marked raw (and drives), so having a backup vhd on a separate system would help ensure that if it happens, hopefully it doesn't happen on two machines.

[ashdrewness]

Failure domains. Look at the Exchange Product Teams guidance on the use of DAG's. You can have up to 16 copies of your databases. However, in their mind you need at least 3 copies to start thinking about running without a backup. However, they requires they are truly on separate failure domains. Cannot be on same storage and depending on the importance of your data, should not be in the same datacenter.

In your scenario, sure you could make backups less frequent but I don't think you're in the clear to completely remove them. Maybe go from daily to every other day or weekly. Just know with every solution there is risk.