gmirror: replacing failed disks

Christian Hiris 4711 at chello.at
Wed Jan 19 17:04:13 PST 2005


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Wednesday 19 January 2005 22:53, you wrote:
> On Wed, Jan 19, 2005 at 06:55:53AM +0100, Christian Hiris wrote:

[...]

> >
> > 2.2. Blank out gmirror metadata on ad4
> >      # dd if=/dev/zero of=/dev/ad4 bs=512 skip=156301400
>
> This command took "a long time" and I didn't let it complete.  I use the
> tcsh and would occassionaly hit <ctrl> T to track it's progress.  I
> didn't see it writing data to the disk nor did I see disk activity.  Did
> I not wait long enough?

Ooops, I just realized that option 'skip=n' skips the blocks on the *input* 
file. The correct option to "skip" blocks on the outfile is 'seek=n'. It 
didn't damage anything in our case, but it waisted your time. Sorry about 
this  mistaken option and the time you lost from this. The command's only 
purpose is to re-design the drive, as if it hasn't ever faced the gmirror 
framework before. 
       
Just for the archives the corrected (and double-checked) command: 

   2.2. Blank out gmirror metadata on ad4
        # dd if=/dev/zero of=/dev/ad4 bs=512 seek=n
        where n=(metadata_location_in_bytes/512)-1

[...]

> Christian,
>
> Other than the issue with 2.2 above, the procedure worked and the
> "replacement" drive is now synchronizing.  Now I'll print out a
> transcript of this and tape it to the box,  Then, in three years, when a
> drive dies, I'll remember what to do :)
>
> Thanks again for all your help.

Just in case, if the tape fails :)

   http://freebsd.rambler.ru

It's excellent!

Good luck,
ch

- -- 
Christian Hiris <4711 at chello.at> | OpenPGP KeyID 0x3BCA53BE 
OpenPGP-Key at hkp://wwwkeys.eu.pgp.net and http://pgp.mit.edu
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.6 (FreeBSD)

iD8DBQFB7wOK09WjGjvKU74RAuzzAJ97NfgwdPng100HzfDOqItmGo4xfQCfeNhW
wQzw3GGrB/oWrWcWobrcEwI=
=x6Rz
-----END PGP SIGNATURE-----


More information about the freebsd-questions mailing list