Move a replicated Mtree from one Data Domain to another

Question

I have an mtree that is being replicated between Data Domains in two data centers (DD1 => DD2).  I need to move the destination mtree from one DD to another in the same data center (DD2 => DD3).  FYI - all systems are DD9500s.  To accomplish this, I started by configuring cascading replication so the mtree that is replicated from DD1 to DD2 is then replicated to DD3 (DD1 => DD2 => DD3).  This was successfully initialized and now all three mtrees are fully synced. Now I need to figure out the next steps.  Here is what I am planning: Disable & delete both replication pairs, DD1 => DD2, and DD2 => DD3; Create & enable replication from DD1 => DD3; Once the new replication pair is fully initialized and synced, delete the mtree on DD2 to recover the capacity. I'm hoping, but I'm not certain that since the mtree replica on DD3 is already a copy of the original mtree on DD1 that the initialization and sync will go fairly quickly (we're talking about ~92TB of data - after dedupe and compression). Is this the right way to do this or is there a better approach? Thanks in advance

GonMur · Answer

Your theory is great, but I have a bad new.

The replication from D1 to D3, still needs to read and split in chunks of information all the data.

For every chunk it will ask D3... Do you have this fingerprint?

If target has the reference, the data will not be sent over the network. If it does not have the reference it will sent it over the network.

In few words... even when the data is already at destination (as you stated), it is not going to be very fast, as it still needs to read the data.

Bear in mind also, that an mtree replication cannot be configured against an mtree that exists, so you probably will have to rename the mtree at D3, before establishing the new replication context.

Cheers,

Gonzalo

Data Domain

Was this post helpful?