Hi, The method depends a bit if you use a distributed-only system (like me) or a replicated setting. I'm using a distributed-only setting (many bricks on different servers, but no replication). All my servers boot via network, i.e., on a start, it's like a new host.
To rescue the old bricks, just set up a new server this the same OS, the same IP and and the same hostname (!very important). The simplest thing would be if you could retrieve the files in /var/lib/glusterd If you install a completely new server (but with the same IP and the same hostname), _then_ restore the files in /var/lib/glusterd, you can just use it as before. It will be recognised as the previous peer, without any additional commands. In fact, I think that /var/lib/glusterd/*... should be identical on all servers, except /var/lib/glusterd/glusterd.info <http://glusterd.info/> which holds the UUID of the server. However, you should be able to retrieve the UUID from the command: gluster pool list This is your scenario 2a) Note that if it's __not__ a distributed-only system, other steps might be necessary. Your 2b) scenario should also work, but slightly different. (Again, only distributed-only) I use it occasionally for failover mode, but I haven't tested it extensively: gluster v reset-brick NameOfVolume FailedServer:/path/to/brick start gluster v add-brick NameOfVolume NewServer:/path/to/brick force # Order is important! # if brick is removed before other brick is added, # will lead to duplicate files. gluster v remove-brick NameOfVolume FailedServer:/path/to/brick force gluster v rebalance NameOfVolume fix-layout start If it's also replcated or striped or using sharding, then other steps might be necessary. best wishes, Stefan Solbrig -- Dr. Stefan Solbrig Universität Regensburg Fakultät für Informatik und Data Science 93040 Regensburg > Am 09.06.2024 um 15:00 schrieb k...@kg-fds.de: > > Hi all, > > I know there are many tutorials on how to replace a gluster host that has > become unusable. But they all seem to assume that the bricks of the > respective host are gone, too. > > My problem is different and (I hope) more easily solved: the disk with the > host’s root file system died and cannot be recovered. However, all of its > bricks are on separate disks and completely undamaged. > > I‘m seeking your advice on what is best practice for replacing such a host. > > My notion is that it should be possible to setup a new root system, configure > it and have it use the existing bricks. > > My questions are: > > 1) Is this a good idea at all or do I miss anything? Would it be better to > format the existing bricks and start over with a completely clean new host, > like most of the tutorials do? > > 2) If it is feasible to use the existing bricks, two scenarios come to my > mind: > > a) Setup a new root file system for a gluster host and copy/change gluster > configuration from one of the existing hosts. Adjust it so that the newly > setup host actually thinks it is the old host (that died). I.e., copying over > the gluster UID, Volume configurations, Hostnamen, IP, etc. (What else would > it need?) > The pool would then recognize the new host as identical to the old one > that died and accept it just like the old host came online again. > > b) Setup a new root file system for a gluster host and probe it into the > trusted pool, with a new name and new gluster UID. Transfer bricks of the old > host that died to the new one using „change-brick“. There would be no need > for lengthy syncing as most of the data is existing and up-to-date on the new > host (that has the bricks of the old host), only self-heal would take place. > > > Do these scenarios sound sane to you and which one would be best practice in > this situation? This is a production system, so safety is relevant. > > > Thanks for any helpful comments and opinions! > > Best, R. Kupper > > ________ > > > > 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@gluster.org > https://lists.gluster.org/mailman/listinfo/gluster-users
________ 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@gluster.org https://lists.gluster.org/mailman/listinfo/gluster-users
