HPE Storage Users Group

Hi All,

I have 2x v400 which are being replaced by 2x 7440C's. Each DC has 1x v400 and 1x 7440C. On the v400's we're replicating data both ways using RCIP.

We need to migrate all data to the 7440's but I'm trying to avoid having to resync the entire capacity of the arrays. Peer motion is configured, tested, and working well v400>7440.

The problem I have is I need to simultaneously move data at both sides from the old array to the new then hope to setup RC, hit go, and only have a relatively small delta. I seem unable to do this with a full resync happening each time.

I've seen the HP Peer Motion guide with gives a poorly written example (IMO) for migrating one side of an RC relationship but not both.

If possible I really need to peer motion both sides to minimise the period we don't have RC running.

Any help/guidance appreciated.

This is supported without full resync but can be pretty complex, it's all down to keeping a snapshot at both ends as the resync point when you admit the newly peer motioned volume.

From memory it's somewhere along these lines

Peer motion the primary and importvv will then take a snapshot as part of the import process. Sync should be fairy straight forward, async periodic will need a final syncrcopy issuing to get the two in sync before stopping the RC group. Then you can dismiss the old volume and resync from the new primary to the secondary

The process is slightly different between primary and secondary array sides as you need to manually create snaps on both sites prior to peer motioning the secondary volumes, for sync the snaps can be online, for async RC needs to be stopped momentarily. Then peer motion the snap from the old secondary to the new secondary, stop RC and reconfigure again using the snap as the resync point.

That may or may not be entirely accurate, but you get the idea of the importance of snaps as a resync point.

I believe the process is covered in the peer motion guide, if not check the RC guide.