You'll indeed need to register the VMware hosts in MDSM yourself. There is no agent to have a VMware host register itself on the SAN (unlike Windows and regular linux). You may be able to find the WWN of the SAS HBA in the SAS controller's bios. The only other way I know to ensure you register the correct WWN with the server is intrusive, but not that hard: - shut down your Windows servers (the SQL cluster) - shut down the VMware servers - power down the MD3220 - power up the MD3220 - power up one of the Windows servers (one that has MDSM on it) - power up 1 of the VMware servers In MDSM you can now register this first VMware server. Power up the other 2 servers and register the 2nd VMware server. I have found that just shutting down 1 VMware server doesn't clear the MD's memory of which WWNs are connected and there is no way to find which ports are registering the WWNs in question.
I have two R620s which are going to server as VM hosts for multiple web servers (in a Windows NLB), and two other R620s which will be configured as physical database servers (in a Failover Cluster), and all with be talking to a single MD3220 SAS array. The DB cluster will host the shared databases on one virtual disk and a shared  datastore on another virtual disk on the array. The ESXi hosts will store their vmx/vmdk files elsewhere on the array. I'm still awaiting delivery of the second DB server, but in the meantime, I've installed the first and it is successfully talking to the array - I run MDSM on this server and the server has successfully connected to the DB and filestore volumes. I assume that I will have little problem with the second server. I've installed ESXi on both VM hosts. I assume the next step is to register them in MDSM, but MDSM doesn't automatically register them as unassigned host port identifiers. Should it? My next guess would be to manually identify the host port identifiers, but how can I determine what their respective identifiers are? I couldn't see anything obvious in the BIOS. I currently have two independent VM hosts with ESXi v5.1 installed - I haven't created a vCenter VM yet because the host doesn't have access to the array for storage(!), therefore I can pair the hosts together for HA etc. As a broader question, given what I am trying to achieve, how should I being going about this?
Connecting 2 ESXi hosts to MD3220 SAS Array