EMC – Boot from SAN MSCS Cluster configuration

Disclaimer: I haven’t done a Windows-based CLARiiON host-attach activity in about 4 or 5 years. And it’s been a bit longer than that since I did boot from SAN configurations. So you can make of this what you will. We’ve been building a Windows 2008 R2 Boot from SAN cluster lately. We got to the point where we were ready to add the 60+ LUNs that the cluster would use. The initial configuration had 3 hosts in 3 storage groups with their respective boot LUNs. I had initially thought that I’d just create another Storage Group for the cluster’s volumes and add the 3 hosts to that. All the time I was trying to remember the rule about multiple hosts or multiple LUNs in a Storage Group. And of course I remembered incorrectly.

To get around this issue, I had to add each LUN (there are about 67 of them) to each Storage Group for the cluster nodes. And ensure that they had consistent host IDs across the Storage Groups. Which has worked fine, but isn’t, as Unisphere points out, recommended. There’s also an issue with the number of LUNs I can put in a Consistency Group (32) – but that’s a story for another time.

EMC – Unisphere Host Agent installation

It’s obviously been quite a while since I’ve used Windows as a platform for block connectivity, as I was unaware of the changes to the installation routine. However, for those of you who don’t cope well with change, you can still edit agent.config manually with the IP addresses of the SPs you want to talk to.

VirtualCenter and Windows 2008 Guest Customisation

I spent some time last week deploying VirtualCenter 2.5 Update 3. As I mentioned previously, some things have improved. And some things haven’t. I don’t know how long Windows 2008 has been out, although I’m sure the Exchange Guy could help me out there. In any case, it’s been more than a few weeks. So I had to build a few Windows 2008 templates last week. But, hey, guess what? When you deploy from template you get this gem:

Cool. Very helpful. If you were using RIS or WDS or whatever Microsofties are calling it today, this wouldn’t be a problem. But we weren’t. There is a workaround that has been documented here. It basically involves telling VirtualCenter the guest is Vista rather than Windows 2008. It then runs through and lets you customise the guest before deploying. I can here MCSEs crying in anguish already … but it _does_ work. But it’s messy. And this was after I’d shown the customer how “streamlined” the VC installation process was. So, maybe there’s a bit more to do before it’s pretty enough.