We are thinking about purchasing 4 x EqualLogic PS6510X SANs (the Sumo boxes). Each has 48 x 600GB 10k SAS drives.
They will be stacked to form a logical pool of storage (all in the same location).
I understand that when you create a RAID group its done on a "per box" basis. So one box could be Raid 50, another Raid 10 etc.
My question is, should I make one box a "performance" box ie Raid 10, and the other boxes "standard" ie Raid50? How do people configure their EQL arrays in the real world?
That really depends on what your requirements are.
We have some PS6010XV's and we have them teired. Current active (write-heavy) data goes on RAID10 15k, reporting stuff goes to RAID6 15k, and archive stuff goes to RAID6 on 7.5k SATA disks.
For example, it's end of financial year tomorrow. So tomorrow the new FY11-12 database will go online on the RAID10 array (well, it's already online, but it will go into production), and the FY10-11 will be moved to the RAID6 data for EOFY reporting. All the reports and invoices that will be generated (approx 150,000 PDF invoices will be generated in the next 48 hours, not to mention tax statements, superannuation summaries, and all the fun things that happen at the end of the financial year) will just go straight to the archive storage.
Dell have very good documentation about suggested configurations, from software and RAID settings to the way to set up your switches and cabling. I remember reading their stuff from 7.30am till about 10.30pm planning the new SAN deployment. I suggest you also do the same, especially with such a massive cash outlay investment.
The 'magical' way to use EqualLogic is just to put all of the arrays into one group. You will get the advantage of spreading out a volume over three arrays and using the I\O of 12 GB (4 each) as well as a ton of spindles. EQL is meant to get better at performance as you add units to it :) That being said, it depends :)