VMware HBA's and Multiple SANs

[Steven Williams]

I have never done this before, nor would I ever think of it but here is what needs to be done and the questions I have.

I have a single VMware Cluster with 4 Hosts. All hosts have 2 x 2 port HBAs that connect to a pair of MDS 9100's. We have a VNX 5400 that is connected to the same pair of MDS's.

Everything is working and now they want to connect a VNX 5300 to the same MDS's and have the same VMware Cluster be able to access that VNX as well as the current one. We do not have any extra HBAs for the ESXi hosts.

I have zoning as 1 initiator to 2 targets on the VNX 5400. Can the SAME initiators access the secondary SAN as well as the primary SAN? Will this cause traffic congestion?

[dynamoxxx]

Steven, why you say SAN i assume you are referring to the storage array ?  If yes, then absolutely yes, you can connect the same HBA to multiple arrays. I would create brand new zones for VNX 5300 ports and host HBAs.  I have systems that are connected to 3 arrays at the same time (VNX, VMAX and XtemIO)

[Steven Williams]

So single port is moving traffic to all three arrays at the same time?

[dynamoxxx]

yep

[Steven Williams]

So your zoning looks like this:

Zone 1

Initiator Host 1 HBA 1

SAN 1 SP A1

SAN1 SP B1

Zone 2 

Initiator Host 1 HBA 1

SAN 2 SP A1

SAN 2 SP B1

Zone 3

Initiator Host 1 HBA 1

SAN 3 SP A1

SAN 3 SP B1

Does this cause an issue with traffic congestion?

[dynamoxxx]

yep, that's my zoning. Don't call your storage arrays SAN, SAN is storage area network ..confuses people :-)

Each array/port appears to your host as unique target so the host knows how to talk to each, but you are correct that you have to watch port utilization of your HBAs (as well as your array ports), regardless if you are connecting to one array or multiple.