ZFS unable to import pool

[Johan Hendriks]

op 23-04-14 12:01, Hugo Lombard schreef:
> Hello
>
> In your original 'zpool import' output, it shows the following:
>
>         Additional devices are known to be part of this pool, though their
>         exact configuration cannot be determined.
>
> I'm thinking your problem might be related to devices that's supposed to
> be part of the pool but that's not shown in the import.
>
> For instance, here's my attempt at recreating your scenario:
>
>    # zpool import
>       pool: t
>         id: 15230454775812525624
>      state: DEGRADED
>     status: One or more devices are missing from the system.
>     action: The pool can be imported despite missing or damaged devices.  The
> 	  fault tolerance of the pool may be compromised if imported.
>       see: http://illumos.org/msg/ZFS-8000-2Q
>     config:
>    
> 	  t                        DEGRADED
> 	    raidz1-0               DEGRADED
> 	      md3                  ONLINE
> 	      md4                  ONLINE
> 	      md5                  ONLINE
> 	      md6                  ONLINE
> 	      3421664295019948379  UNAVAIL  cannot open
> 	  cache
> 	    md1s2
> 	  logs
> 	    md1s1                  ONLINE
>    #
>
> As you can see, the pool stattus is 'DEGRADED' instead of 'UNAVAIL', and
> I don't have the 'Additional devices...' message.
>
> The pool imports OK:
>
>    # zpool import t
>    # zpool status t
>      pool: t
>     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
> 	  t                        DEGRADED     0     0     0
> 	    raidz1-0               DEGRADED     0     0     0
> 	      md3                  ONLINE       0     0     0
> 	      md4                  ONLINE       0     0     0
> 	      md5                  ONLINE       0     0     0
> 	      md6                  ONLINE       0     0     0
> 	      3421664295019948379  UNAVAIL      0     0     0  was /dev/md7
> 	  logs
> 	    md1s1                  ONLINE       0     0     0
> 	  cache
> 	    md1s2                  ONLINE       0     0     0
>    
>    errors: No known data errors
>    #
>
> As a further test, let's see what happens when the cache disk
> disappears:
>
>    # zpool export t
>    # gpart delete -i 2 md1
>    md1s2 deleted
>    # zpool import
>       pool: t
>         id: 15230454775812525624
>      state: DEGRADED
>     status: One or more devices are missing from the system.
>     action: The pool can be imported despite missing or damaged devices.  The
> 	  fault tolerance of the pool may be compromised if imported.
>       see: http://illumos.org/msg/ZFS-8000-2Q
>     config:
>    
> 	  t                        DEGRADED
> 	    raidz1-0               DEGRADED
> 	      md3                  ONLINE
> 	      md4                  ONLINE
> 	      md5                  ONLINE
> 	      md6                  ONLINE
> 	      3421664295019948379  UNAVAIL  cannot open
> 	  cache
> 	    7736388725784014558
> 	  logs
> 	    md1s1                  ONLINE
>    # zpool import t
>    # zpool status t
>      pool: t
>     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
> 	  t                        DEGRADED     0     0     0
> 	    raidz1-0               DEGRADED     0     0     0
> 	      md3                  ONLINE       0     0     0
> 	      md4                  ONLINE       0     0     0
> 	      md5                  ONLINE       0     0     0
> 	      md6                  ONLINE       0     0     0
> 	      3421664295019948379  UNAVAIL      0     0     0  was /dev/md7
> 	  logs
> 	    md1s1                  ONLINE       0     0     0
> 	  cache
> 	    7736388725784014558    UNAVAIL      0     0     0  was /dev/md1s2
>    
>    errors: No known data errors
>    #
>
> So even with a missing raidz component and a missing cache device, the
> pool still imports.
>
> I think some crucial piece of information is missing to complete the
> picture.
>
Did you in the past add an extra disk to the pool?
This could explain the whole issue as the pool is missing a whole vdev.

regards
Johan