zfs discuss - Jul 2009 - ZFS Mirror : drive unexpectedly unplugged

Hi !

I''m a Mac User, but I think that I will get more response here about
this question than on a Mac forum.
And first, sorry for my approximative English.

I have a ZFS Pool named "MyPool" with two device (two external USB
drive), configured as mirror :

NAME              STATE     READ WRITE CKSUM
MyPool            ONLINE       0     0     0
  mirror          ONLINE       0     0     0
    /dev/disk2s2  ONLINE       0     0     0
    /dev/disk3s2  ONLINE       0     0     0


The drive disk3 is unexpectedly unplugged for some reason (power failure, etc),
but the drive is perfectely functional.

I have plugged an other driver before replugging the unplugged drive. This new
drive take the device name "disk3"...
So, if I plug again the unplugged drive, the drive take the device name
"disk4" and my ZFS mirror partition the name "disk4s2".

Here is my problem. If I scrub my pool, he don''t recognize the new
device name. It seem that the only solution is to export and import again the
pool, because :
- If I do a detach of disk3s2 and a attach of disk4s2, he say to me that the
drive is not of the good size (it''s exact, but I have no problem with
this when I create my mirrored pool).
- If I do a attach of disk4s2 on disk2s2, it say to me that disk3s2 is busy
(it''s suspicious : the drive is not used)
- If I do a replace, ZFS seem to resilver the totality of the drive (and this
can take age to finish !), but the drive doesn''t need to be fully
resilvered, no (when the drive is unplugged, the drives are in the same stat) ?

So what is the official method to say to ZFS that the device name was changed
without exporting and re-importing the pool.
-- 
This message posted from opensolaris.org

I don''t have an answer to your question exactly because i''m a
noob and i''m
not using mac but i can say that on FreeBSD which i''m using atm there
is a
method to name devices ahead of time so if the drive letters change you
avoid this exact problem.  I''m sure opensolaris and mac have something
similar.

As far as your issue goes i THINK you can just export/import the
pool.....i''m sure someone in this list who knows more than me will
speak up
on offical stuff =)

2009/7/28 Av?rous Julien-Pierre <no-reply at opensolaris.org>
> Hi !
>
> I''m a Mac User, but I think that I will get more response here
about this
> question than on a Mac forum.
> And first, sorry for my approximative English.
>
> I have a ZFS Pool named "MyPool" with two device (two external
USB drive),
> configured as mirror :
>
> NAME              STATE     READ WRITE CKSUM
> MyPool            ONLINE       0     0     0
>  mirror          ONLINE       0     0     0
>    /dev/disk2s2  ONLINE       0     0     0
>    /dev/disk3s2  ONLINE       0     0     0
>
>
> The drive disk3 is unexpectedly unplugged for some reason (power failure,
> etc), but the drive is perfectely functional.
>
> I have plugged an other driver before replugging the unplugged drive. This
> new drive take the device name "disk3"...
> So, if I plug again the unplugged drive, the drive take the device name
> "disk4" and my ZFS mirror partition the name "disk4s2".
>
> Here is my problem. If I scrub my pool, he don''t recognize the new
device
> name. It seem that the only solution is to export and import again the
pool,
> because :
> - If I do a detach of disk3s2 and a attach of disk4s2, he say to me that
> the drive is not of the good size (it''s exact, but I have no
problem with
> this when I create my mirrored pool).
> - If I do a attach of disk4s2 on disk2s2, it say to me that disk3s2 is busy
> (it''s suspicious : the drive is not used)
> - If I do a replace, ZFS seem to resilver the totality of the drive (and
> this can take age to finish !), but the drive doesn''t need to be
fully
> resilvered, no (when the drive is unplugged, the drives are in the same
> stat) ?
>
> So what is the official method to say to ZFS that the device name was
> changed without exporting and re-importing the pool.
> --
> This message posted from opensolaris.org
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss at opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
>
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Thank you for you response, wonslung.

I can export / import, yes, but for this I should unmount all filesystems
depending of the pool, and it''s not always possible (and it''s
sad to be forced to do that).

For the same name device, I don''t know how to do that. I will search
for this.
-- 
This message posted from opensolaris.org

There is a little mistake :

"If I do a attach of disk4s2 on disk2s2, it say to me that disk3s2 is busy
(it''s suspicious : the drive is not used)"

The good version is :

"If I do a attach of disk4s2 on disk2s2, it say to me that disk4s2 is busy
(it''s suspicious : the drive is not used)"

(disk3s2 is no more concerned by ZFS in this case)
-- 
This message posted from opensolaris.org

sometimes the disk will be busy just from being in the directory or if
something is trying to connect to it.

Again, i''m no expert so i''m going to refrain from commenting
on your issue
further.


2009/7/28 Av?rous Julien-Pierre <no-reply at opensolaris.org>
> There is a little mistake :
>
> "If I do a attach of disk4s2 on disk2s2, it say to me that disk3s2 is
busy
> (it''s suspicious : the drive is not used)"
>
> The good version is :
>
> "If I do a attach of disk4s2 on disk2s2, it say to me that disk4s2 is
busy
> (it''s suspicious : the drive is not used)"
>
> (disk3s2 is no more concerned by ZFS in this case)
> --
> This message posted from opensolaris.org
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss at opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
>
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