One vDS or two vDS?

[e2p2]

I'm using vCenter 5.5.  I have two clusters each composed of 4 hosts.  Each host has dual 10GB NICs.  The pair of NICs on each host is connected to a standard vSwitch using Cisco Etherchannel and IP Hash load balancing.  VLAN Trunking is utilized so any VLAN on the campus network can be accessed by each standard vSwich.  I also have iSCSI setup on each host utilizing VMkernel port bindings, each cluster has dedicated iSCSI storage.  The standard vSwitch on each host has port groups for only the VLANS that each cluster needed for the VMs running on that cluster.  The Clusters have some of the same VLANs setup on the hosts vSwitch.  My Port Groups for VLANs use a common naming format, EX VL172s (VLAN 172 for standard switch) or VL196d (VLAN 196 for distributed switch).  I have created one vDS and converted Clutser#2 to use this vDS.  I have migrated the existing NICs, Port Groups, and VMs for Cluster#2 to the vDS.

Now to the question in the Title.  Should I use this one vDS for Cluster#1 or should I create a new vDS for Cluster#1.  If I use the same vDS for Cluster #1 I will have some Port Groups (VLANs) that will not be used.  If I create a new vDS for Cluster#1 I will have to create Port Groups for the some of the same VLANs but with different names (since two port goups, even on different vDS, cannot have the same name).

[chriswahl]

Unless you have plans to migrate workloads across clusters in vSphere 5.5, I'd lean towards two VDS in this situation. The clusters are not similar enough to justify all the extra dancing around with names, and having extra fault domains with clean VDS configurations is a plus. And vSphere.next has already announced the ability to migrate across VDSs, so the only real advantage to having one "large" VDS would be simplified management.

[e2p2]

The Clusters are more or less identical, my apologies if my description above gave the opposite impression.  The exception is that some vlans were not needed by the VMs on Cluster#2.  I would like to vMotion some of the VMs between clusters, this is not possible right now because Cluster#1 uses a vSwitch and Cluster#2 uses a vDS.

[chriswahl]

Excellent. Let's turn "I would like to vMotion some of the VMs between clusters" into a requirement and alter the design to a single VDS.

[e2p2]

Excellent.  This is what I was thinking, but I wanted a second opinion.  Thank you.