switching back from replicated environment

[terrance101]

Hi guys,

we've got the replicated environment flying and everything seems to be coming up roses. But the query remains, if we're going from the replicated environment (say we had to run off it for 2 days) then we need to get back to the live environment, is it possible to veeam back? I know you should technically never be overwriting the original production environment machine but is this a possiblity and if so are there any pitfalls?

[veremin]

So, you just want to perform failover to DR site, run on replicated VMs for a while, then, get everything back to production site, overwriting original VMs with those from DR site, right?

If so, there is a special option called Failback that is designed specifically for this use case. In a nutshell, it’s a process of switching from the VM replica to the production VM. During failback, Veeam Backup & Replication uses the working replica to recover the original VM to the latest state (state of working replica).

More information regarding it can be found in the corresponding User Guide (p. 56).

Thanks.

[terrance101]

Tnx very much.

[yizhar]

Hi.

The replica failback has 2 downsides:

* You need to run in a temporary status on the DR side, to allow failback (i.e., you cannot commit or complete the failover process).
* Failback will take much longer to sync back the latest changes from DR site back to production.

Therefor I consider it a good option for short term, but for long run of the DR site you can use the approach discussed here:

Community Forums • View topic - Failover on DR site
Failover on DR site

In a nutshell:
complete and commit failover to DR site.
reconfigure reverse replication from DR to production.
When you need to revert back from DR to production, use the regular failover process in reverse direction (instead of failback).

The method you choose depends on several factors:
How long will VM run at DR site.
Amount of changes.
Bandwidth.
Downtime requirements during failover/failback (failover can be much quicker then failback).
Simplicity (failback is simplier then reconfiguration of reverse replication).
Is it ok for you to run from VMware snapshots at DR site (I think you cannot commit them if you plan to use failback, but with reverse replication you can).

Anyway - I suggest that you create a test VM, and practice both approaches on it.
failover to DR site.
Make some changes (copy 100gb for example).
failback, or use reverse replication (practice both methods).

Yizhar