This guy would have more predictible performance and higher reliability if he had organized the array as two 12-drive raidz2 vdevs (instead of 18-drive and 6-dr

This guy would have more predictible performance and higher reliability if he had organized the array as two 12-drive raidz2 vdevs (instead of 18-drive and 6-drive). The reasons are because (1) the chances of triple drive failure though low is higher in a 18-drive vdev than in a 12-drive one, and (2) performance (IOPS) is variable between two asymmetrical vdevs. There is very rarely a good reason for doing asymmetrical vdevs in a single ZFS pool. I approve of his choice of HBA (based on the SAS2008 chip). For those looking for even bigger setups, I maintain a list of controllers at http://blog.zorinaq.com/?e=10 http://blog.zorinaq.com/?e=10 where you can even find 16-, 24- and 32-port controllers. 8-port ones are the most cost effective as of today. I have been a happy ZFS user for 9 years, both personally and professionally. Using snapshots, running periodical scrubs, having dealt with a dozen of drive failures over the years. Everything works beautifully - it's a pleasure to admin ZFS.