Oh boy, there are a lot of things here :) How many people in your office will be using these services? If it are just 50 people or so, you would probably be fine with just about any configuration. 500 or 5000 would be a different story, and you would have to be much more careful.
If possible, you should measure what your requirements are on existing load. For example, figure out what kind of I/O demands are being generated by each application. It would also be nice to understand the I/O patters, i.e. IO size, read/write ratio, randomness. Then you can use a tool like iometer to simulate your load on the ZFS box from a VM on the ESX box, and figure out what raid sets are required to support your load. Another rough rule of thumb you can use is to sum the read and write IOPS at the 95 percentile (take a good guess), and use this equation to determine how many IOs you will need to support: RAID 10 1 * measured read IOPS + 2 * measured write IOPS RAID 5 1 * read IOPS + 4 * write IOPS Each SATA disk can support in the 100 IOPS range (considering a lot of the IOs are random), and a 15k SAS disk around 200 IOPS. So if your total app load was 500 read and 500 write IOPS, then: raid 10: 500 + 2*500 = 1500 ~10-15 SATA disks ~ 6-8 15k SAS disks raid 5: 500 + 500*4 = 2500 ~20-25 SATA disks ~12-14 SAS disks These are *really* rough numbers, and conservative. Honestly you could spend ages on an IO study like this. There is a ZFS best practices guide out there which makes good reading, and talks to the pros/cons of the different raid types offered by ZFS, how many disks in a single raidz, etc. I think most people using ZFS go with the software raid sets to take advantage of checksums and self healing. Performance on modern hardware is fine. Regarding cards, if you are not going to do HW raid, just get a SAS HBA. It makes life so much simplier. LSI makes a good selection of them. No RAID functionality, just good, fast IO. Attach that to a SAS JBOD, and you can mix and match sata and sas drives to fid your application. If you want to go HW raid, try to get a card that supports JBOD mode so you can use software raid if you change your mind. -Scott -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
