In Dell EMC Unity (OE 4.4), synchronous file replication can provide a zero RPO solution for file resources. The data is mirrored from a source Unity system to remote Unity system over short distances (recommended < 5ms RTT latency). Synchronous file replication supports NAS Servers, file systems and VMware NFS Datastores. The replication connection between two systems can be selected three modes:
Asynchronous – Enable Asynchronous block and file replication.
Synchronous – Enable Synchronous block and file replication.
Both – Enable both Asynchronous and Synchronous replication.
The architecture of file replication:
You can see the NAS on source Unity system at Site A that are replicated to the remote Unity system at Site B.
Replication Operation Options:
Planned Failover (From Source Unity system)
Bring up the remote resources as source and change the direction of replication to original source.
Unplanned Failover (From Destintation Unity system)
Bring up the remote resources as source and break the replication sync session.
After Planned Failover – Bring up the remote resources as source and change the direction of replication to original source.
After Unplanned Failover – Run full sync to original source then failover resources and replicate to original destination.
Pause the existing replication session and stop syncing writes to destination.
After a Pause – Resume replication session to re-sync outstanding writes and continue replication operation.
After Unplanned Failover – Run full sync to original source and restart sync operations from new source.
Delete existing replication session.
Dell EMC Unity – MetroSync (Part 1)
This video will go over the synchronous file replication and snapshot replication as part of the overall MetroSync solution on Dell EMC Unity systems.
Dell EMC Unity – MetroSync (Part 2)
This video will go over snapshot schedule replication, cabinet level failover, and asynchronous replication to a 3rd site as part of the overall MetroSync solution on Dell EMC Unity systems.