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Due to various circumstances I've given myself a crash course on the ZFS file sytem. I need some help getting comfortable with the unknowns. Whatever those are.


  • Running www.zfsonlinux.org on CentOS 6.2
  • I have an array with 12x2TB sata disks.
  • I created a raidz2 pool and a couple zfs file systems inside that.
  • Performance is better than I expected. (How often do you get to say that?)

Some questions:

  • What type of maintenance should I schedule? I have read that doing a "zpool scrub" is advised. At what interval would you run this? Is there anything else to do?
  • Is there any performance monitoring other than "zpool iostat" - snmp?
  • I need to be alerted by email or similar about disk failures, etc.... What are my options?
share|improve this question
24hours..not bad!! :-) – Nikhil Mulley Feb 1 '12 at 12:48

I would almost a zero maintenance once the pool and filesystems are created. zpool scrub is not suggested to be often, but would not hurt to be around once in like two-three months but prefer doing it manually.

Monitoring the zpool status or zpool status -v output should give you a clue whether your pool is healthy or if any of the disks are in degrated state. This also let knows on the scrub status. zpool status -x should get you almost one line answer if you do not need to dig further but just an informational message would not hurt.

On the alerting thing, I do not think there is any tight integration on Linux. I think on Solaris, it is integrated with FM(Fault management), so monitoring the FMA on Solaris can indirectly give you monitoring on Solaris ZFS bad events as well. I think just a wrapper with the above checks would do just fine.

If there are any problems with ZFS, there is always this document however for Solaris specific, but should apply to ZFS layer in most cases.


I congratulate you on choosing ZFS and giving it a try on Linux! :-)

BTW, I am curious to know how much usable filesystem have you got after creating the raidz2 pool.

share|improve this answer
I have 17.7TB of usable space after you get ripped off from hard disk companies and their calculation of what a terabyte is :) and losing 2 disks to parity. I also enabled gzip-1 compression and get 8.56x comp ratio. Nice huh? – LVLAaron Feb 1 '12 at 13:02
Nice!! Include snapshots now ;-) – Nikhil Mulley Feb 1 '12 at 15:22
Already done. :) – LVLAaron Feb 1 '12 at 15:41
Now Deduplication.. I am sure, the list goes on. :-) – Nikhil Mulley Feb 1 '12 at 16:24

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