zfs discuss - Jun 2008 - uncorrectable I/O error ... how to address?

Hi all,

I have a situation I don''t know how to get out of:

I''m trying to ''zfs send'' an FS off of my laptop, but
in the middle of the
send process, it hangs, and I see an message:

"WARNING: Pool ''p'' has encountered an uncorrectable I/O
error. Manual
intervention is required."

that''s all very nice, apart from the fact that I don''t see any
indication
what the manual intervention is supposed to be .. and worse, when I try to 
find out more using "zpool status -v", it hangs (or appears to) after:

# zpool status -v
   pool: p
  state: ONLINE
status: One or more devices has experienced an error resulting in data
         corruption.  Applications may be affected.
action: Restore the file in question if possible.  Otherwise restore the
         entire pool from backup.
    see: http://www.sun.com/msg/ZFS-8000-8A
  scrub: none requested
config:

         NAME        STATE     READ WRITE CKSUM
         p           ONLINE       0     0     2
           c1t0d0s7  ONLINE       0     0     2

errors: Permanent errors have been detected in the following files:

[ hangs ]

both the "zfs send" and "zpool status" seem uninterruptible.

I saw this once before and rebooted, thereafter "zpool status" showed
nothing.

so: how do I find out more about what''s going on and what''s
broken, and how
do I fix it without just deleting the FS?

thx
Michael
-- 
Michael Schuster        http://blogs.sun.com/recursion
Recursion, n.: see ''Recursion''

Michael Schuster wrote:
> Hi all,
> 
> I have a situation I don''t know how to get out of:
I forgot the technical data:

$ uname -a
SunOS paddy 5.11 snv_86 i86pc i386 i86pc

$ zfs upgrade -v
The following filesystem versions are supported:

VER  DESCRIPTION
---  --------------------------------------------------------
  1   Initial ZFS filesystem version
  2   Enhanced directory entries
  3   Case insensitive and File system unique identifer (FUID)
[..]

(btw: is the current version no printed on purpose, or is it understood 
that zfs is always at the latest possible version?)

~$ zpool upgrade -v
This system is currently running ZFS pool version 10.

The following versions are supported:

VER  DESCRIPTION
---  --------------------------------------------------------
  1   Initial ZFS version
  2   Ditto blocks (replicated metadata)
  3   Hot spares and double parity RAID-Z
  4   zpool history
  5   Compression using the gzip algorithm
  6   bootfs pool property
  7   Separate intent log devices
  8   Delegated administration
  9   refquota and refreservation properties
  10  Cache devices
> I''m trying to ''zfs send'' an FS off of my laptop,
but in the middle of the
> send process, it hangs, and I see an message:
> 
> "WARNING: Pool ''p'' has encountered an uncorrectable
I/O error. Manual
> intervention is required."
> 
> that''s all very nice, apart from the fact that I don''t
see any indication
> what the manual intervention is supposed to be .. and worse, when I try to 
> find out more using "zpool status -v", it hangs (or appears to)
after:
> 
> # zpool status -v
>    pool: p
>   state: ONLINE
> status: One or more devices has experienced an error resulting in data
>          corruption.  Applications may be affected.
> action: Restore the file in question if possible.  Otherwise restore the
>          entire pool from backup.
>     see: http://www.sun.com/msg/ZFS-8000-8A
>   scrub: none requested
> config:
> 
>          NAME        STATE     READ WRITE CKSUM
>          p           ONLINE       0     0     2
>            c1t0d0s7  ONLINE       0     0     2
> 
> errors: Permanent errors have been detected in the following files:
> 
> [ hangs ]
> 
> both the "zfs send" and "zpool status" seem
uninterruptible.
> 
> I saw this once before and rebooted, thereafter "zpool status"
showed nothing.
> 
> so: how do I find out more about what''s going on and
what''s broken, and how
> do I fix it without just deleting the FS?
> 
> thx
> Michael

-- 
Michael Schuster        http://blogs.sun.com/recursion
Recursion, n.: see ''Recursion''

Michael Schuster wrote:
> (btw: is the current version no printed on purpose, or is it understood 
> that zfs is always at the latest possible version?)
ah ... I just found the answer to that myself:

# zpool upgrade
This system is currently running ZFS pool version 10.

The following pools are out of date, and can be upgraded.  After being
upgraded, these pools will no longer be accessible by older software versions.

VER  POOL
---  ------------
  8   p

# zfs upgrade
This system is currently running ZFS filesystem version 3.

internal error: unable to get version property
The following filesystems are out of date, and can be upgraded.  After being
upgraded, these filesystems (and any ''zfs send'' streams
generated from
subsequent snapshots) will no longer be accessible by older software versions.


VER  FILESYSTEM
---  ------------
  2   p/csw
  2   p/export
  2   p/home
  2   p/store

Michael
-- 
Michael Schuster        http://blogs.sun.com/recursion
Recursion, n.: see ''Recursion''