VMDK Consistency with SAN based Replication?

[PhilM1973]

Good afternoon. I'm hoping someone can help with a companies query

They have IBM v7000 SAN performing replication via a change log type Lun on the SAN. This goes over a not particularly fast link cross campus to the DR SAN. Replication is set to occur every 5 minutes, however due to bandwidth contention it could well be that it takes 20 minutes + to transmit 5 minutes worth of changes stored on the primary San. The question is, how does VMware handle the VMDK files at the DR site in the event of a primary site failure if not all the recent changes have replicated over? Customer is concerned that a primary site failure would corrupt the DR site VMDK's if a failure occurred during one of these slow / delay replication slots.

Does VMware maintain the integrity of the DR VMDK files etc until ALL expected changes are successfully received? Essentially a last known good copy?

[a_p_]

If I understand this correctly, it's completely SAN based, i.e. not related to vSphere at all. A SAN replication is transparent to vSphere, so unless the IBM storage system's replication takes care of the consistency you might actually end up with corrupted replicas.

André

[PhilM1973]

Thank you Andre, more research has indeed shown this to be entirely a feature of the SAN, in this case the V7000 setup with Global Mirror with Change Volumes ensures a consistent copy on the backup device.

Case closed :smileyhappy: