Networking help for a migration from old hosts/storage to new hosts/storage

[EProbclarke41]

Hi All,

In our current data center we have x4 old IBM hosts all connected to an ageing IBM DS3000 series SAN.

The old hosts are connected to the SAN using FC switches.

I've now installed x5 new HP Proliant hosts and a new NetApp SAN all conected via 10GB Ethernet and iSCSi.

All hosts and storage is under the same vCenter and physically located in the same rack.

I now want to start moving VMs from the old hosts/storage across to the new equipment.  This is where the confusion lies.  The old SAN is FC so there are no VLANS.  The new hosts connect to the new SAN via the new storage VLANs.  What do I need to do to be able to storage vmotion machines from the old FC SAN to the new iSCSi one? 

I can't see a way of getting the storage networks physically connected.  The IBM switch is using a Brocade 200E which seems to be FC only and the new switches are Cisco Nexus 3172 which has x6 FC ports.  Should I be connecting the Nexus switch to the Brocade switch so that the new hosts can access the IBM storage over the FC connection?

Or is there some other way I should be doing this?

Thanks for any assistance! 

[ThompsG · Accepted solution]

Hi EProbclarke41 and welcome to the community!

First things first - the Cisco Nexus 3172 is a networking switch not a FC switch. The 6 ports you see that look very much like FC ports are actually for QSFP to allow 40Gb networking connectivity. This is connected via fibre but it’s not FC.

All this to say you cannot connect your FC SAN to this switch and vice-versa.

You have at least two options at this point:

1. Since vSphere 5.1, it has supported non-shared vMotion (Migration with vMotion in Environments Without Shared Storage). This means you can migrate without the need for the destination host seeing both the source and destination datastore.
2. Your old ESXi hosts have FC HBA and will be able to run the Software iSCSI Adapter. You could present the new iSCSI luns to the old hosts and then Storage vMotion using shared storage.

Kind regards.

[EProbclarke41]

Thanks for getting back to me.

I think I'm going to go with option 2 as these hosts still have a couple of spare Gb ports available.  I'll add the new iSCSi LUNs to the old hosts and then storage vmotion - thanks for your help!

[EProbclarke41]

Sorry just one more question on this - how does the vmotion without storage work? ie which network does it use to move the data?  Also which method would you recommend?