Moving to multi-site

[Quailman]

I have begun looking at changing our single-site, all in one building SAN configuration to multi-site.  We are running NR10 volumes across the board with RAID 5 on the units.  We have a failover manager setup at a third site already too.

Would this work without any downtime?

1.  Setup sites inside of CMC and assign units accordingly (these aren't setup right now)

2.  Power off all of the LH units for the new site

3.  Transport all of the LH units to the new site (praying nothing happens to the rest of the units)

4.  Power on LH units

5.  Everything just works?

OR would it be better to rebuild the multi-site configuration, moving shelves over one at a time?

[oikjn]

Can you describe the 2nd site a bit more?  Generally I think HP suggests to do all at once, but if your sites are really close, it might make sense for you to move them over one at a time.  One thing to be cautious about is the subnets, are you keeping the multi-site san under a single subnet or is it going to be routed?  That will affect what you have to do in order to make it work...  for me, I was setting up a new SAN site so I created a temporary VLAN that became the subnet of the remote site and when the SAN was setup and ready to move, I just shut down everything, deleted the VLAN on the local site and set it up at the remote site and made sure the routing was udated and then everything worked.

[Quailman]

Yep, the second site is connected using a EoMPLS circuit, so we can stretch our layer 2 boundry to it.  I thought about this a bit more, and I think it would be safer to move my units around so I can remove them one at a time from the main cluster and move them without compromising the availability of the cluster.

[oikjn]

what about your network?  is it a flat subnet with both locations or are each individual with their own subnet and a router/gateway?  If the latter, you have to make sure you change the IP address right before you move the node.  MLPS implies at least a decient distance between the sights.  IF you have enough extra storage capacity and the two sites have a different subnet, I would suggest doing the move all at once so you can prep everything locally and then have it up and running in one trip.  Your concern about the period when the 2nd site is down is valid and if you have enough extra space in the san, I would use NR10+1 temporarilly so that while you move the nodes you will still have the redundnacy you want.  I would imagine you should have the space to do this I believe you said you are adding NEW nodes to the system which means you should have the extra space needed for NR10+1