Zpool

simple but functional script to check if your zpools are healthy and send email if they are not…

http://blog.qcnetwork.com/2011/03/monitoring-zpool-with-email-alert.html

http://forums.freebsd.org/showthread.php?t=23127

Unfortunately if you have accidentally added a single drive into your raidz pool at the top-level there is no way to just remove the non redundant disk. Your pool is now dependant on this disk.

If you want your pool to be just raidz vdevs, then you will need to backup your data, destroy your pool, create a new pool, and restore your data.

There is no current way to remove a top-level vdev from a pool.

Recently i hit what i thought was a huge disaster with my ZFS array. Essentially i was unable to import my zpool without causing the kernel to panic and reboot. Still unsure of the exact reason, but it didn’t seem to be due to a hardware fault. (zpool import showed all disks as ONLINE)

When i tried to import with zpool import -f tank the machine would lockup and reboot (panic).

If you dont have the disks available to build up a zpool and have a play with zfs you can actually just use files created with the mkfile command… The commands are exactly the same.

mkfile 64m disk1

mkfile 64m disk2

mkfile 64m disk3

mkfile 10m disk4

mkfile 100m disk5

mkfile 100m disk6

Now you can create a zpool using the above files… (i’m using raidz for this setup)

zpool create test raidz /fullpath/disk1 /fullpath/disk2 /fullpath/disk3

This is quite a good diagnostic for checking your disk throughput. Try copying data to and from your zpool while your running this command on the host…

zpool iostat -v unprotected 2

capacity     operations    bandwidth
pool         used  avail   read  write   read  write
----------  -----  -----  -----  -----  -----  -----
unprotected  1.39T   668G     18      7  1.35M   161K
c7d0       696G   403M      1      2  55.1K  21.3K
c9d0       584G   112G      8      2   631K  69.3K
c7d1       141G   555G      8      2   697K  70.0K
----------  -----  -----  -----  -----  -----  -----

The above command will keep displaying the above output every 2 seconds (average during that time). I’ve used it a few times to ensure that all disks are being used (in write operations) where needed. Of course read op’s may not be typically across all disks as it will depend where the data is…

I’ve had a play with WHS but eventually got annoyed with its lack of performance. Yes i know its not built for performance and typically is used just as a backup / simple store with duplication as redundancy, just i couldn’t stand the speed of the thing. If you were ever unlucky enough (even post power pack 1) to do a copy during the “data moving” the performance was even worse. On a positive note nothing beats it if you have a heap of non-similar sized disks that you want to put together (with redundancy) as a single shared storage pool.