[Gluster-users] How to re-sync

Stephan von Krawczynski skraw at ithnet.com
Sun Mar 7 11:17:43 UTC 2010


I love top-post ;-)

Generally, you are right. But in real-life you cannot trust on this
"smartness". We tried exactly this point and had to find out that the clients
do not always select the correct file version (i.e. the latest) automatically.
Our idea in the testcase was to bring down a node, update its kernel an revive
it - just as you would like to do it in real world for a kernel update.
We found out that some files were taken from the downed node afterwards and
the new contents on the other node got in fact overwritten.
This does not happen generally, of course. But it does happen. We could only
stop this behaviour by setting "favorite-child". But that does not really help
a lot, since we want to take down all nodes some other day.
This is in fact one of our show-stoppers.


On Sun, 7 Mar 2010 01:33:14 -0800
Liam Slusser <lslusser at gmail.com> wrote:

> Assuming you used raid1 (distribute), you DO bring up the new machine
> and start gluster.  On one of your gluster mounts you run a ls -alR
> and it will resync the new node.  The gluster clients are smart enough
> to get the files from the first node.
> 
> liam
> 
> On Sat, Mar 6, 2010 at 11:48 PM, Chad <ccolumbu at hotmail.com> wrote:
> > Ok, so assuming you have N glusterfsd servers (say 2 cause it does not
> > really matter).
> > Now one of the servers dies.
> > You repair the machine and bring it back up.
> >
> > I think 2 things:
> > 1. You should not start glusterfsd on boot (you need to sync the HD first)
> > 2. When it is up how do you re-sync it?
> >
> > Do you rsync the underlying mount points?
> > If it is a busy gluster cluster it will be getting new files all the time.
> > So how do you sync and bring it back up safely so that clients don't connect
> > to an incomplete server?
> >
> > ^C
> > _______________________________________________
> > Gluster-users mailing list
> > Gluster-users at gluster.org
> > http://gluster.org/cgi-bin/mailman/listinfo/gluster-users
> >
> _______________________________________________
> Gluster-users mailing list
> Gluster-users at gluster.org
> http://gluster.org/cgi-bin/mailman/listinfo/gluster-users
> 


-- 
MfG,
Stephan von Krawczynski


------------------------------------------------------
ith Kommunikationstechnik GmbH

Lieferanschrift  : Reiterstrasse 24, D-94447 Plattling
Telefon          : +49 9931 9188 0
Fax              : +49 9931 9188 44
Geschaeftsfuehrer: Stephan von Krawczynski
Registergericht  : Deggendorf HRB 1625
------------------------------------------------------




More information about the Gluster-users mailing list