If you want Free HA, then the XEN hypervisor on another platform ( Citrix Xen is just a rehash of the opensource XEN hypervisor) such as SUSE can be made to do HA. Not looked at it for a long time though.
You can even build a VM to be your "test" storage server .
Hey I am not meaning to put spanners in the works there is a lot of good advice around, and I am not saying "DO NOT EVER USE A SAN", just letting you know that SANS(s) are not the be all and end all for either uptime or performance, I've been there and done that and when it came to replacing our SANS, I just simply decided not to replace them at all.
I had two SANS, one of them failed catastophically within 3 years. Deep down, I couldn't then trust the other one either even though it did stay up until I decomissioned it. I've had tens of physical hosts over the years and i've only ever lost one outright. Thats not a good ratio for the SANS and I hear about problems with SANS and NAS's in other schools in my area all the time.
If you can justify spending th £££'s going for the full on 99.9999% uptime then by all means go for it. I couldnt justify it based on the fact that my budgets are being cut year on year and some years I have not even been able to have a technician. When we couldn't afford a £15k technician I could not justify spending £15k on SANS.
@AButters - (Sorry to thread hijack) What manufacturer was your SAN? (Tier 1? Sun, LeftHand, NetAPP, EMC?)
I'm intrigued by those Infortrend boxes... they're mega-cheap!
Tier 1. That's all your gonna get out of me sorry ;)
Fair enough! :D
Build a test environment and don't waste thousands on stuff untill your sure your happy with what's going on.
Theres other costs that will mount up, L3 switch, UPS, Backup device.
Dell PowerEdge 1850 1U server, ideal terminal/web server | eBay
Bit of extra ram for £10 and you haev a smart little virtual host for 2-3 servers or more if your frugal on the specs ;)
Really i think going by what you want or rather what you're not 100% sure you want :p you need to go back to step 1....as you've kind of started a few steps ahead of yourself :D
Sit down analyse what exactly you want to achieve from all this, analsyse what the various ways you can achieve that by comparing different products and their features, then move on to what hardware you want and how you're going to implement your hardware, proper planning is key to implementing a good virtualised infrastructure :)
And don't forget, optimal configuration is 90% of the task, fast/big fancy hardware will only get you so far for so long.
Depends on the hypervisor you want to use as hyper-v won't work on the PE2800 or PE1850 plus a load others.
A recent 64Bit Desktop ( anything in the last 4 years or so ) will also most likly support Various Hypervisors, I have run Vmware and Citrix Xen on a Dell Optiplex 740 , Lenovo Athalon X2 64 ( on an ITX board USFF pC ).
Interesting discussions here, and some of you guys have an IT budget that would put a banking corporation to shame.
I'm in kinda same position really. I do appreciate the benefits of virtualisation but I'm of the attitude that it needs to be done properly if you are going to bung all your servers into a SAN, that is DOUBLE up on everything for redundancy. I've recently priced up a very nice 3 host and SAN with fibre switch, and even utilising my existing equipment the whole project was approaching £30k+ which very hard to justify to Bursar when to him it looks like 4 boxes and a shed load of cables lol. So back to what Abutters mentioned using local hosts and good backups...this might be better solution for some. It's also setting up realistic expectations with SLAs with the SMTs, although in truth all this will go out of the window when they can't host a class due to 1 hour downtime.
So I'm on a crossroad as well .... Does one choose a well designed VM+ SAN ? Local storage with VMs ? Go back to old school, single servers with good backups? Maybe looking at important servers in the school(fileservers,exchange,sql) and clustering those?