[NBLUG/talk] Odd Raid Setup

[gandalf at sonic.net]

I'm putting this out on socosa and nblug. Hope this doesn't anger 
anyone.

debian 6.0.3

question filesystem: zfs Raid 6 - solaris filesystem


I've got a weird setup with two raid6 arrays each of about 11T. The odd 
thing is how they are arranged. The one raid is mounted on /vmath and 
the other raid is mounted on /vmath/video. The actual video files are 
stored within /vmath/video. This seems really odd. Does anybody here 
know what's going on? Is this just an odd way to get a 22T raid array?

root at vmath:~# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md0              226G  3.5G  211G   2% /
tmpfs                 4.0G     0  4.0G   0% /lib/init/rw
udev                  4.0G  372K  3.9G   1% /dev
tmpfs                 4.0G     0  4.0G   0% /dev/shm
vmath                  11T  128K   11T   1% /vmath
vmath/video            22T   11T   11T  51% /vmath/video

root at vmath:/etc# zfs list
NAME          USED  AVAIL  REFER  MOUNTPOINT
vmath        10.8T  10.6T  62.8K  /vmath
vmath/video  10.7T  10.6T  10.7T  /vmath/video

root at vmath:/etc# zpool status
   pool: vmath
  state: DEGRADED
status: One or more devices could not be used because the label is 
missing or
         invalid.  Sufficient replicas exist for the pool to continue
         functioning in a degraded state.
action: Replace the device using 'zpool replace'.
    see: http://www.sun.com/msg/ZFS-8000-4J
  scan: resilvered 24.8M in 0h1m with 0 errors on Mon Dec 29 10:23:10 
2014
config:

         NAME        STATE     READ WRITE CKSUM
         vmath       DEGRADED     0     0     0
           raidz2-0  ONLINE       0     0     0
             sdn     ONLINE       0     0     0
             sdm     ONLINE       0     0     0
             sdl     ONLINE       0     0     0
             sdk     ONLINE       0     0     0
             sdr     ONLINE       0     0     0
             sdq     ONLINE       0     0     0
             sdp     ONLINE       0     0     0
             sdo     ONLINE       0     0     0
           raidz2-1  DEGRADED     0     0     0
             sdf     ONLINE       0     0     0
             sde     ONLINE       0     0     0
             sdd     ONLINE       0     0     0
             sdc     ONLINE       0     0     0
             sdj     ONLINE       0     0     0
             sdi     UNAVAIL      0     4     0
             sdg     ONLINE       0     0     0
             sdh     UNAVAIL      9   129     3

errors: No known data errors


root at vmath:~# cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name 
devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
# / was on /dev/md0 during installation
UUID=4eaa682b-9eef-48b0-baa8-d045f9ea5ca0 /               ext4    
relatime,user_xattr,errors=remount-ro 0       1
# swap was on /dev/sda1 during installation
UUID=15d027a5-3ee5-40f2-9f83-b5f50f83ba67 none            swap    sw     
          0       0
# swap was on /dev/sdb1 during installation
UUID=3efecbd4-631e-4b3f-a6d4-99d7eb750b14 none            swap    sw     
          0       0
/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto     0       0