We are into the project of building a 48 drives iSCSI SAN, it would be the base of 8 Xen Servers running about 300+ VM instances, so high performance it's really important as you may guess
After our first research we are considering the following:
- SuperMicro 417E16-R1400UB or 417E26-R1400UB (http://www.supermicro.com/products/chassis/4U/417/SC417E26-R1400U.cfm)
Basically difference is about the SAS Expanders, one is E16 Single Expander chip and the other E26 Dual Expander chip (Both SAS2 6Gb/s)
Not decided yet, but it would be SuperMicro (As is our main hardware provider) probably with the following specs:
Dual Xeon 5600 Series
48 GB RAM (To use as cache)
Not decided yet, basically we are checking out Intel to use DCA to reduce network interrupts, and/or cards which support iSCSI offload.
Here is the big thing, actually the only RAID controller we've found which supports 48 drives RAID10 is Adaptec 5 Series, but we are unsure about the performance of this card for this setup. But as you may see in the link below it supports +32 drives in an unique RAID10 array.
We are thinking about using WD Velociraptor 600GB drives, as we had really good experience in the past with these drives, but we are open to other possibilities, only requirement is that the drive should be at least 10.000RPM and 2,5" form factor (Also drives with less than 600GB per drive are suitable)
iSCSI target Software:
We are considering two solutions, starwind and Open-e, actually we prefer StarWind as it is able to manage a huge amount of RAM as WriteBack cache for the system (We plan to use the 48GB of RAM for that) and as we plan a Active/Active HA setup, even if one of the SANs goes offline, there would not be data loss, as the other SAN would be replicated synchronously.
Good point of Open-e is that it would allow as to have 2 x 24 drives RAID 10, and merge them into just one RAID0 array, but cache management of StarWind seems like a really huge benefit.
So, if anybody could provide advice about the following questions, we would really apreciate :
1.- Do you know or recommend any controller for 48 drives RAID 10 array?
2.- Experiences with Open-e or StarWind software, any recommendations?
3.- Obviously any other suggestion or tip to improve our setup would be highly appreciate .
Thanks a lot for your help! (And sorry about my english, I'm not native english speaker )