Linux – ZFS: Trying to remove top-level drive from Zpool

freebsdlinuxzfs

I have a zpool called storage that contains a five device raidz1 array.

Today I went and bought another 3TB device and put it in my enclosure. However, instead of creating a new pool and adding that device to it, I made a mistake and added it to my existing storage pool.

Now I have a top-level device that I want to remove called sdg (that's the new drive). Every time I try to remove it I get:

cannot remove sdg: only inactive hot spares, cache, top-level, or log devices can be removed.

So how do I remove this device now? If this device fails, my entire pool will be unavailable. I'm thinking I should go buy another drive and at least it will be mirrored, but I just can't believe there isn't a proper way to do this.

This is my status dump:

pool: storage
state: ONLINE
scan: scrub canceled on Wed Jul 23 17:26:08 2014

config:

 NAME                                 STATE     READ WRITE CKSUM
 storage                              ONLINE       0     0     0
   raidz1-0                           ONLINE       0     0     0
     ata-ST3000DM001-1CH166_Z1F1PYM6  ONLINE       0     0     0
     ata-ST3000DM001-1CH166_W1F24CSC  ONLINE       0     0     0
     ata-ST3000DM001-1CH166_W1F2372R  ONLINE       0     0     0
     ata-ST3000DM001-1CH166_W1F24BTK  ONLINE       0     0     0
     ata-ST3000DM001-1CH166_Z1F2KKLW  ONLINE       0     0     0
   sdg                                ONLINE       0     0     0

errors: No known data errors

Best Answer

Unfortunately, removing a vdev (which this drive is) from a pool is not supported by ZFS currently (but there is work ongoing to support it). The work around would be to dump your data out of the pool and recreate it, then put the data back.

Related Solutions

Linux – How to replace a disk in a non-redundant ZFS pool

Don't know if things were that different in `13 but 'zfs replace' works on non-redundant pools. You just run the 1 command instead of detaching first.

d1 is 1G, d2 is 2G, both are empty files in /tmp:

/t/test #> zpool create test /tmp/test/d1
/t/test #> zpool set autoexpand=on test
/t/test #> zpool status
  pool: test
 state: ONLINE
  scan: none requested
config:

    NAME            STATE     READ WRITE CKSUM
    test            ONLINE       0     0     0
      /tmp/test/d1  ONLINE       0     0     0

errors: No known data errors
/t/test #> zpool list
NAME    SIZE  ALLOC   FREE  EXPANDSZ   FRAG    CAP  DEDUP  HEALTH  ALTROOT
test   1008M   258K  1008M         -     0%     0%  1.00x  ONLINE  -


/t/test #> zpool replace test /tmp/test/d1 /tmp/test/d2


/t/test #> zpool status
  pool: test
 state: ONLINE
  scan: resilvered 61K in 0h0m with 0 errors on Sun Sep 18 18:55:32 2016
config:

    NAME            STATE     READ WRITE CKSUM
    test            ONLINE       0     0     0
      /tmp/test/d2  ONLINE       0     0     0

errors: No known data errors
/t/test #> zpool list
NAME    SIZE  ALLOC   FREE  EXPANDSZ   FRAG    CAP  DEDUP  HEALTH  ALTROOT
test   1.98G   408K  1.98G         -     0%     0%  1.00x  ONLINE  -

Freebsd – How to remove broken ZIL disk from ZFS pool

There is an option which allows to import pool with a broken device. Her is how I managed to recover the pool:

# zpool export tank
# zpool import -m tank
# zpool status tank
  pool: tank
 state: DEGRADED
status: One or more devices could not be opened.  Sufficient replicas exist for
the pool to continue functioning in a degraded state.
action: Attach the missing device and online it using 'zpool online'.
   see: http://illumos.org/msg/ZFS-8000-2Q
  scan: none requested
config:

NAME                    STATE     READ WRITE CKSUM
tank                    DEGRADED     0     0     0
 mirror-0              ONLINE       0     0     0
   gpt/disk1           ONLINE       0     0     0
   gpt/disk2           ONLINE       0     0     0
logs
 6324139563861643487   UNAVAIL      0     0     0  was /dev/md1
cache
 gpt/disk3             ONLINE       0     0     0

errors: No known data errors
# zpool clear tank
# zpool remove tank 6324139563861643487
# zpool status tank
  pool: tank
 state: ONLINE
  scan: none requested
config:

NAME                    STATE     READ WRITE CKSUM
tank                    ONLINE       0     0     0
 mirror-0              ONLINE       0     0     0
   gpt/disk1           ONLINE       0     0     0
   gpt/disk2           ONLINE       0     0     0
cache
 gpt/disk3             ONLINE       0     0     0

errors: No known data errors

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