So I'm interested to know what people are doing for Boot from SAN with VNX storage groups when using ESXi as I had a conversation with someone today and I'd never really looked into this much before.

Obviously with boot from SAN you need ensure that you present a LUN 0 to each host for the boot LUN.  Obviously you can only have one LUN 0 per storage group so that basically means constructing a storage group for each ESXi host and adding a boot LUN with the Host LUN Unit (HLU) set to 0.

When you consider how to add the LUNs for the VMware datastores you could look at creating a storage group with all the datastore LUNs included and adding all the hosts. Unfortunately you can only have a host in a single Storage Group at any one time, so that won't work as the host is already in a storage group for the boot from SAN LUN.

So it appears that your only alternative is to use a storage group for each ESXi Host and add the boot from SAN LUN and the Datastore LUNs and manage it on a per host basis. This isn't a problem in a small environment but if you have a number of 32 host clusters??!!  Adding a LUN quickly becomes a laborious task when you need to add it to 32 storage groups (scripting would speed this up but it still seems a bit cumbersome and potentially error prone)

I'm aware on UCS you can get quite clever through the creation of multiple virtual HBA's but unfortunately that's not an option in this particular instance.

http://virtualeverything.wordpress.com/2011/05/31/simplifying-san-management-for-vmware-boot-from-san-utilizing-cisco-ucs-and-palo/

Interested to know if anyone is doing something different for this or whether you've simply bitten the bullet and done it on a per host basis.

Craig Stewart

vSpecialist Technical UK/I

www.virtualpro.co.uk