[Gluster-users] Directory in split brain does not heal - Gfs 9.2

Ilias Chasapakis forumZFD chasapakis at forumZFD.de
Wed Aug 17 11:35:48 UTC 2022


Hi Thomas,

Thanks again for your replies and patience :)

We have also offline backups of the files.

So, just to verify I understood this correctly, deletion of a 
.glusterfs-gfid file doesn't inherently include the risk of the loss of 
the complete brick, right?

I saw you already applied this for your purposes so it worked for you... 
But just as a confirmation. Of course it is fully understood that the 
operational risk is on our side.

It is just an "information-wise" question :)

Best regards
Ilias

Am 17.08.22 um 12:47 schrieb Thomas Bätzler:
>
> Hello Ilias,
>
> Please note that you can and should backup all of the file(s) involved 
> in the split-brain by accessing them over the brick root instead of 
> the gluster mount. That is also the reason why you’re not in danger of 
> a failure cascade wiping out our data.
>
> Be careful when replacing bricks, though. You want that heal to go in 
> the right direction 😉
>
> Mit freundlichen Grüßen,
>
> i.A. Thomas Bätzler
>
> -- 
>
> BRINGE Informationstechnik GmbH
>
> Zur Seeplatte 12
>
> D-76228 Karlsruhe
>
> Germany
>
> Fon: +49 721 94246-0
>
> Fon: +49 171 5438457
>
> Fax: +49 721 94246-66
>
> Web: http://www.bringe.de/ <http://www.bringe.de/>
>
> Geschäftsführer: Dipl.-Ing. (FH) Martin Bringe
>
> Ust.Id: DE812936645, HRB 108943 Mannheim
>
> *Von:* Gluster-users <gluster-users-bounces at gluster.org> *Im Auftrag 
> von *Ilias Chasapakis forumZFD
> *Gesendet:* Mittwoch, 17. August 2022 11:18
> *An:* gluster-users at gluster.org
> *Betreff:* Re: [Gluster-users] Directory in split brain does not heal 
> - Gfs 9.2
>
> Thanks for the suggestions. My question is if the risk is actually 
> related to only losing the file/dir or actually creating 
> inconsistencies that span through the bricks and "break everything".
> Of course we have to take action anyway for this not to spread (as we 
> already now have a second entry that developed an "unhealable" 
> directory split-brain) so it is just a question of evaluation before 
> acting.
>
> Am 12.08.22 um 18:12 schrieb Thomas Bätzler:
>
>     Am 12.08.2022 um 17:12 schrieb Ilias Chasapakis forumZFD:
>
>         Dear fellow gluster users,
>
>         we are facing a problem with our replica 3 setup. Glusterfs
>         version is 9.2.
>
>         We have a problem with a directory that is in split-brain and
>         we cannot manage to heal with:
>
>             gluster volume heal gfsVol split-brain latest-mtime /folder
>
>         The command throws the following error: "failed:Transport
>         endpoint is not connected."
>
>         So the split brain directory entry remains and and so the
>         whole healing process is not completing and other entries get
>         stuck.
>
>         I saw there is a python script available
>         https://github.com/joejulian/glusterfs-splitbrain Would that
>         be a good solution to try? To be honest we are a bit concerned
>         with deleting the gfid and the files from the brick manually
>         as it seems it can create inconsistencies and break things...
>         I can of course give you more information about our setup and
>         situation, but if you already have some tip, that would be
>         fantastic.
>
>     You could at least verify what's going on: Go to your brick roots
>     and list /folder from each. You have 3n bricks with n replica
>     sets. Find the replica set where you can spot a difference. It's
>     most likely a file or directory that's missing or different. If
>     it's a file, do a ls -ain on the file on each brick in the replica
>     set. It'll report an inode number. Do a find .glusterfs -inum from
>     the brick root. You'll likely see that you have different gfid-files.
>
>     To fix the problem, you have to help gluster along by cleaning up
>     the mess. This is completely "do it at your own risk, it worked
>     for me, ymmv": cp (not mv!) a copy of the file you want to keep.
>     On each brick in the replica-set, delete the gfid-file and the
>     datafile. Try a heal on the volume and verify that you can access
>     the path in question using the glusterfs mount. Copy back your
>     salvaged file using the glusterfs mount.
>
>     We had this happening quite often on a heavily loaded glusterfs
>     shared filesystem that held a mail-spool. There would be parallel
>     accesses trying to mv files and sometimes we'd end up with
>     mismatched data on the bricks of the replica set. I've reported
>     this on github, but apparently it wasn't seen as a serious
>     problem. We've moved on to ceph FS now. That sure has bugs, too,
>     but hopefully not as aggravating.
>
>     MfG,
>
>     i.A. Thomas Bätzler
>
>     -- 
>
>     BRINGE Informationstechnik GmbH
>
>     Zur Seeplatte 12
>
>     D-76228 Karlsruhe
>
>     Germany
>
>     Fon: +49 721 94246-0
>
>     Fon: +49 171 5438457
>
>     Fax: +49 721 94246-66
>
>     Web:http://www.bringe.de/
>
>     Geschäftsführer: Dipl.-Ing. (FH) Martin Bringe
>
>     Ust.Id: DE812936645, HRB 108943 Mannheim
>
>
>
>     ________
>
>     Community Meeting Calendar:
>
>     Schedule -
>
>     Every 2nd and 4th Tuesday at 14:30 IST / 09:00 UTC
>
>     Bridge:https://meet.google.com/cpu-eiue-hvk
>
>     Gluster-users mailing list
>
>     Gluster-users at gluster.org
>
>     https://lists.gluster.org/mailman/listinfo/gluster-users
>
> -- 
> forumZFD
> Entschieden für Frieden | Committed to Peace
> Ilias Chasapakis
> Referent IT | IT Consultant
> Forum Ziviler Friedensdienst e.V. | Forum Civil Peace Service
> Am Kölner Brett 8 | 50825 Köln | Germany
> Tel 0221 91273243 | Fax 0221 91273299 |http://www.forumZFD.de  <http://www.forumZFD.de>
> Vorstand nach § 26 BGB, einzelvertretungsberechtigt | Executive Board:
> Oliver Knabe (Vorsitz | Chair), Jens von Bargen, Alexander Mauz
> VR 17651 Amtsgericht Köln
> Spenden | Donations: IBAN DE37 3702 0500 0008 2401 01 BIC BFSWDE33XXX

-- 
forumZFD
Entschieden für Frieden | Committed to Peace

Ilias Chasapakis
Referent IT | IT Consultant

Forum Ziviler Friedensdienst e.V. | Forum Civil Peace Service
Am Kölner Brett 8 | 50825 Köln | Germany

Tel 0221 91273243 | Fax 0221 91273299 |http://www.forumZFD.de

Vorstand nach § 26 BGB, einzelvertretungsberechtigt | Executive Board:
Oliver Knabe (Vorsitz | Chair), Jens von Bargen, Alexander Mauz
VR 17651 Amtsgericht Köln

Spenden | Donations: IBAN DE37 3702 0500 0008 2401 01 BIC BFSWDE33XXX

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20220817/7f3911c4/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature
Type: application/pgp-signature
Size: 665 bytes
Desc: OpenPGP digital signature
URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20220817/7f3911c4/attachment.sig>


More information about the Gluster-users mailing list