Migration from iscsi to Fiber and 5.5 to 6

[jscottweber]

So I have a project going now, where I am trying to move from iscsi connected storage to fiber connected storage using 2 datastores.  Adding 2 new hosts and removing 4 old hosts. I have 8 hosts that I need to change, but I do not have the down time to just shut down and migrate over and bring back up. So I am trying to find the best possible scenarios for this move. So far I have 3 hosts moved over to fiber, but the other 5 I do not.  What I am running into is the fact I have DRS off so I have to manually managed my vm's so I'm not over taxing any one host. So I was thinking of making temp cluster to move my 4 old hosts that I do not plan to update or use that way I can keep my most critical data/vm's on there while I prep and move all my others vm's to the new 6.0.0u1 fiber connected hosts. But I'm not sure if that is the right way to approach this.  And I'm sure I have missed something while typing this all out, but I'm trying to find the best way to describe what I have and what I am trying to accomplish. Just looking for some thoughts, or ideas as I have never made this kind of move before. Thanks for your time.

[a_p_ · Accepted solution]

I did this a couple of times in the past, and what you describe should work just fine. If you don't have lots of cluster settings which you want to keep (ie. you can easily configure them on a new cluster) simply create a new DRS/HA cluster with the new hosts, migrate VMs to free up hosts on the old cluster, move/reinstall the old hosts to the new cluster, and then continue with migrating the remaining VMs. If the hosts in the new cluster are CPU compatible (i.e. share the same EVC mode) the migration can be done without downtime.

Some additional thoughts:

• If you are running VM based/Hot-Add backups. make sure that the backup appliances are available on both clusters with access to the appropriate datastores.
• Depending on the storage systems, you may benefit (I/O performance) from distributing the VMs across more than just 2 datastores.

André

[jscottweber]

Thanks for the help.

This actually worked better than I had hoped...  I am still in the process or migrating from the old iscsi datastore to the new datastore, but I have all hosts in place and working now.

I didn't even use a second cluster.  So now I have 6 hosts (3 on each chassis) with HA and DRS so all is well.

Thanks for your reply.