EqualLogic SAN (Part 2)
So, in Part 1 I talked about the whole process of borrowing and setting up my EqualLogic PS3800XV SAN. 
Now that I've got it powered up, I needed to add IP addresses for it, and connect to it. Setting IP addresses is straightforward - you can let DHCP handle it, or use the provided null modem cable to log in to the SAN command line interface and issue a few commands to get it done. All this is detailed in their docs, though they generally assume you'll do everything over the web or the graphical interface. And if I had had the x64 version of their Remote Setup Wizard available when I started, I wouldn't have needed the CLI at all. But since I didn't have an x64 version of it to start, no sweat, I just had to telnet into the SAN to do the setting. They provided the cable, after all, and it was long enough to easily reach. A nice touch. Just fire up HyperTerminal, set it to 9600 baud, 8N1, and you're in business.
Once IP addresses are set up, the next step is to install the software. Ooops - the shipping version doesn't support Windows Server 2003 x64 Edition, much less the x64 version of Windows Server 2008. An email to support got me the first (and it's probably the shipping version by now), and a couple more emails to my press contact got me on the beta for the second. We're in business.
Now if I'd only wanted to use their software, and their interface (rather than needing to use the Microsoft Storage Manager for SANs because I was writing about it), I'd have actually had an even easier time of it. Their software is good, and includes all the options you'd usually pay more for. My favourite option that is included, by the way, is called "thin provisioning". Think of this as sort of like dynamically expanding disks in Virtual Server. You don't actually commit disk space until it's needed, allowing you to better manage overall disk utilization on the SAN. And since you can always add more disk space by plugging in another unit, you can build out your infrastructure logically as needed from the beginning, but not have to plunk down all your cash for the actual hardware until you need to. I like it.
The actual setup of your first LUN is straightforward. First, open their Group Manager application, and set the RAID policy. The choices are RAID-10 (striping on top of mirrored sets), RAID-50 (striping on top of RAID-5 arrays), or simple RAID-5 (but configured with a spare disk). For my purposes, I chose RAID-5, but if I were doing this for a production network hosting many VMs, I'd have chosen RAID-10. Virtualization is very write intensive, so you need to design your disk strategy accordingly.
Next, create a volume, assigning it a Volume Name and a size. You can also specify a snapshot reserve space (100% is the default). Specify the iSCSI access for the volume (CHAP, IP address, or iSCSI Initiator name), and you're done. At least on the SAN side. Now you just need to connect the server that will be using the volume to it, using whatever iSCSI initiator you are using. I used the built-in iSCSI initiator in Windows Server 2008 (but you can download one for Server 2003 here). And I was lazy and didn't use CHAP for authentication, but in a real world scenario, I'd recommend it.
Once connected, open Disk Manager (or DiskPart.exe if you're a dedicated command line type), and bring the volume online, initialized and assign partitions, etc to it just as you would any local hard disk. (Don't make it a dynamic volume - they're just a bad idea with SANs. And all the RAID stuff is already being taken care of by the SAN, so what's the point.)
Speed? Well, once I got things set up, I created eight(8) Windows Server 2008 RC0 server virtual machines, ranging from a single CPU, 1GB gateway VM, to an x64, dual proc, 8 GB Terminal Server VM, all on that same volume and started getting serious. I don't have any concrete benchmarks - just real world use in my environment. The SAN is as fast, or faster, than the local SAS array on this server. And that's darned fast!
So, overall, am I happy? Oh, yeah. Except that I don't get to keep it. Even though it really isn't an appropriate unit for the average home office, this SAN is so well made, and so redundant, that I can't NOT want it. And trust me, I'd find a simple solution to the noise problem. In fact, I've already got a spot picked out, and it even vents to the outside. Just need to run CAT6 to it, and I'm in business. So, if the folks at EqualLogic want to leave it here for an extended test? Say 3 years or so? No problem, I'll be happy to keep using it and writing about it. Hmmm, I wonder just how many hours of TiVo I can fit on it?