On Thu, 2018-03-08 at 18:49 +0100, Mevo Govo wrote: > Hi, > thanks for advice and your intrest. > We would use oracle database over DRBD. Datafiles (and control and > redo files) will be on DRBD. FRA also (on an other DRBD device). But > we are new in DRBD, and DRBD is also a component what can fails. We > plan a scenario to recover the database without DRBD (without data > loss, if possible). We would use nfs or local filesystem for this. If > we use local FS, the control file is out of sync on the B node when > switch over (from A to B). We would copy controlfile (and redo files) > from DRBD to the local FS. After this, oracle can start, and it keeps > the controlfiles syncronized. If other backup related files (archlog, > backup) are also available on the local FS of either node, we can > recover the DB without DRBD (without data loss) > (I know it is a worst case scenario, because if DRBD fails, the FS on > it should be available at least on one node) > Thanks: lados.
Why not use native database replication instead of copying files? Any method getting files from a DRBD cluster to a non-DRBD node will have some inherent problems: it would have to be periodic, losing some data since the last run; it would still fail if some DRBD issue corrupted the on-disk data, because you would be copying the corrupted data; and databases generally have in-memory state information that makes files copied from a live server insufficient for data integrity. Native replication would avoid all that. > 2018-03-07 10:20 GMT+01:00 Klaus Wenninger <kwenn...@redhat.com>: > > On 03/07/2018 10:03 AM, Mevo Govo wrote: > > > Thanks for advices, I will try! > > > lados. > > > > > > 2018-03-05 23:29 GMT+01:00 Ken Gaillot <kgail...@redhat.com > > > <mailto:kgail...@redhat.com>>: > > > > > > On Mon, 2018-03-05 at 15:09 +0100, Mevo Govo wrote: > > > > Hi, > > > > I am new in pacemaker. I think, I should use DRBD instead > > of copy > > > > file. But in this case, I would copy a file from a DRBD to > > an > > > > external device. Is there a builtin way to copy a file > > before a > > > > resource is started (and after the DRBD is promoted)? For > > example a > > > > "copy" resource? I did not find it. > > > > Thanks: lados. > > > > > > > > > > There's no stock way of doing that, but you could easily > > write an > > > agent > > > that simply copies a file. You could use ocf:pacemaker:Dummy > > as a > > > template, and add the copy to the start action. You can use > > standard > > > ordering and colocation constraints to make sure everything > > happens in > > > the right sequence. > > > > > > I don't know what capabilities your external device has, but > > another > > > approach would be to an NFS server to share the DRBD file > > system, and > > > mount it from the device, if you want direct access to the > > original > > > file rather than a copy. > > > > > > > csync2 & rsync might be considered as well although not knowing > > your scenario in detail it is hard to tell if it would be overkill. > > > > Regards, > > Klaus > > > > > -- > > > Ken Gaillot <kgail...@redhat.com <mailto:kgail...@redhat.com> > > > > > > _______________________________________________ > > > Users mailing list: Users@clusterlabs.org > > > <mailto:Users@clusterlabs.org> > > > https://lists.clusterlabs.org/mailman/listinfo/users > > > <https://lists.clusterlabs.org/mailman/listinfo/users> > > > > > > Project Home: http://www.clusterlabs.org > > > Getting started: > > > http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > > > <http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf> > > > Bugs: http://bugs.clusterlabs.org > > > > > > > > > > > > > > > _______________________________________________ > > > Users mailing list: Users@clusterlabs.org > > > https://lists.clusterlabs.org/mailman/listinfo/users > > > > > > Project Home: http://www.clusterlabs.org > > > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scra > > tch.pdf > > > Bugs: http://bugs.clusterlabs.org > > > > _______________________________________________ > > Users mailing list: Users@clusterlabs.org > > https://lists.clusterlabs.org/mailman/listinfo/users > > > > Project Home: http://www.clusterlabs.org > > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratc > > h.pdf > > Bugs: http://bugs.clusterlabs.org > > > > _______________________________________________ > Users mailing list: Users@clusterlabs.org > https://lists.clusterlabs.org/mailman/listinfo/users > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch. > pdf > Bugs: http://bugs.clusterlabs.org -- Ken Gaillot <kgail...@redhat.com> _______________________________________________ Users mailing list: Users@clusterlabs.org https://lists.clusterlabs.org/mailman/listinfo/users Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org