ZFSv28, zfs list behaviour and sysutils/freebsd-snapshot

[J. Hellenthal]

On Mon, 14 Mar 2011 04:30, mikael.urankar@ wrote:
> On Mon 14 March 2011 at 02:44:16AM -0400, J. Hellenthal wrote:
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>>
>>
>> On Thu, 10 Mar 2011 08:17, mikael.urankar@ wrote:
>>> Hi,
>>>
>>> I'm using sysutils/freebsd-snapshot to make periodic ZFS backup snapshot
>>> and this soft is broken since the upgrade of my pool to ZFSv28.
>>> After some debugging it appears that "zfs list" behaviour has changed
>>> with ZFSv28, and since freebsd-snapshot relies on "zfs list" to retrieve
>>> the "ZFS file system name" from the "mountpoint name" the soft doesn't
>>> work anymore.
>>>
>>> output of "zfs list" on a 8.2R amd64 (ZFSv15) :
>>> zfs list /home/murankar
>>> NAME                 USED  AVAIL  REFER  MOUNTPOINT
>>> tank/home/murankar  1.47M  1.59T  1.47M  /home/murankar
>>>
>>> zfs list tank/home/murankar
>>> NAME                 USED  AVAIL  REFER  MOUNTPOINT
>>> tank/home/murankar  1.47M  1.59T  1.47M  /home/murankar
>>>
>>> on a 9-Current amd64 I've got no output for "zfs list /home/murankar"
>>> and a exit code of 1
>>> the output of "zfs list tank/home/murankar" is correct :
>>> NAME                 USED  AVAIL  REFER  MOUNTPOINT
>>> tank/home/murankar  6,56G   286G  6,55G  /home/murankar
>>
>> Looking at the output here I am hoping that this is not hand typed! the
>> character ',' appears in this output which might fool a script into doing
>> other things if it has not been avoided in the first place.
>
> This is not hand typed and depends on the locale in use :
>
> zfs list tank/home/murankar
> NAME                 USED  AVAIL  REFER  MOUNTPOINT
> tank/home/murankar  6,65G   286G  6,58G  /home/murankar
>
> setenv LANG en_US.UTF8
> zfs list tank/home/murankar
> NAME                 USED  AVAIL  REFER  MOUNTPOINT
> tank/home/murankar  6.65G   286G  6.58G  /home/murankar
>
> freebsd-snapshot set LC_ALL and LANG to C
>
>>
>> If you have upgraded that machine to 9-CURRENT and have
>> sysutils/zfsnap installed I would recommend deleting any snapshots
>> that you have before it runs the snapshot scripts. This assumes that the
>> snapshot script might have changed since you upgraded it and that the
>> snapshot names are different. Better to be on the sane side.
>>
>> See UPDATING/20100929 for reference.
>
> I've deleted all old snapshots before running the snapshot scripts, but
> to not avail.
>
>>
>> # Correct syntax:
>> zfs list pool/dataset1/dataset2
>>
>> # Incorrect syntax: ( I hope you were hand typing that and missed... )
>> zfs list /dataset1/dataset2
>
> In fact I was only doing by "hand" what freebsd-snapshot is doing.
> See op_make() from /usr/local/sbin/snapshot (near line 285) :
>
>     #   operate on filesystem
> +    echo "XXX zfs list $fs_dir"
>     if [ ".$zfs_enabled" = .yes ] && (zfs list $fs_dir) >/dev/null
> 2>&1; then
>
> /usr/local/sbin/snapshot make -g4 /var:test
> XXX zfs list /var
>
>>
>>>
>>> Is it the normal behaviour for ZFSv28 or some kind of regression ?
>>>
>>
>> No its not normal, and some sort of regression possible. Though I usually
>> take regression as performance issues as in speed.
>>
>> Also,
>>
>> pkg-descr
>> freebsd-snapshot is a set of convenience front-end tools to mount(8)
>> and mdconfig(8) for the management of UFS2 snapshots.  It is
>> also the under-lying tool used in the periodic snapshot
>> scheduler periodic-snapshot(8) and the mounting/unmouning
>> command in the amd(8) map /usr/local/etc/amd.map.snap. It
>> provides the making, expiring, visiting, mounting and
>> unmounting of filesystem snapshots.
>>
>> pkg-descr
>> zfSnap is simple sh script to make rolling zfs snapshots with cron. Main
>> advantage of zfSnap is that it's written in %100 pure /bin/sh, doesn't
>> require any additional software to run, and is simple to use.
>>
>> zfSnap keeps all information about snapshot in snapshot name. zfs snapshot
>> names are in form: Time-stamp--TTL where time-stamp is date and time of
>> snapshot creation and TTL is Time To Live in human readable form.
>>
>>
>> Did you happen to mix the above two up ? If so then rinse and repeat.
>>
>
> Nope, freebsd-snapshot can handle ZFS snapshot and it uses to work fine
> with ZFSv{14,15}, see the copyright notice :
> FreeBSD UFS/ZFS Snapshot Management Environment, the pkg-descr file
> seems outdated.
>
> Thanks for your help.
>

Since this is s locale dependent script I have added the maintainer to the 
CC so he can adjust it properly upstream.

A simple ( export LC_ALL=C ) to the top of the script should fix it 
permanently.


-- 

  Regards,

  J. Hellenthal
  (0x89D8547E)
  JJH48-ARIN