-------- Original-Nachricht -------- > Datum: Mon, 14 Sep 2009 21:14:32 +0200 > Von: Stephan von Krawczynski <skraw@xxxxxxxxxx> > An: Anand Avati <avati@xxxxxxxxxxx> > CC: gluster-devel@xxxxxxxxxx > Betreff: Re: solutions for split brain situation > On Mon, 14 Sep 2009 21:44:12 +0530 > Anand Avati <avati@xxxxxxxxxxx> wrote: > > > > Our "split brain" is no real split brain and looks like this: Logfiles > are > > > written every 5 mins. If you add a secondary server that has 14 days > old > > > logfiles on it you notice that about half of your data vanishes while > not > > > successful self heal is performed, because the old logfiles read from > the > > > secondary server overwrite the new logfiles on your primary while new > data is > > > added to them. > > > > Have you been using favorite-child option? > > No, the option was not used. > > > Auto resolving of > > split-brain is bound to make you lose data of one of the subvolumes. > > If you had indeed specified favorite-child option, and the > > favorite-child option happens to be the server which had 14day old > > logs, what just happened was exactly what was in the elaborate warning > > log. > > > > Now what is more interesting for me is, the sequence of taking down > > and bringing up the servers you followed to split brain? Was is really > > just taking one server (any of them) down and bringing it back up? Did > > you face a split brain with just this? Can you please describe the > > minimal steps necessary to reproduce your issue? > > Take 2 servers and one client. Use a minimal replicate setup but do _not_ > add > the second server. Copy some data on the first server via glusterfs, then > rsync that data on the second server directly from the first server > (glusterfsd not yet active there). Now change some of the data to have > files > that are really newer as your rsync cycle. Then start glusterfsd on the > second > server. Your client will add it. Then open the newer files r/w on the > client. > You will notice the split brain messages in the client logs and find that > every > other file gets indeed read in from the second (outdated) server fileset. > Write it back and your newer files on the first server are gone. > As said, no favorite child option set. > You just rsynced but did you synced the extended attributes as well? > > Avati > > -- > Regards, > Stephan > > > _______________________________________________ > Gluster-devel mailing list > Gluster-devel@xxxxxxxxxx > http://lists.nongnu.org/mailman/listinfo/gluster-devel -- Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3 - sicherer, schneller und einfacher! http://portal.gmx.net/de/go/atbrowser
