<HTML>
<HEAD>
<TITLE>Re: [DRBD-user] RedHat Clustering Services does not fence when DRBD breaks</TITLE>
</HEAD>
<BODY>
<FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>Well, yes, that’s exactly the problem; when one node broke, fencing (from the RHCS level) wouldn’t be enacted, and things would go South very quickly.<BR>
<BR>
I’ll give your suggestion a try in our dev environment, and let you know how it goes.<BR>
<BR>
Thanks Jakov!<BR>
<BR>
On 11/23/10 1:16 AM, "Jakov Sosic" <<a href="jakov.sosic@srce.hr">jakov.sosic@srce.hr</a>> wrote:<BR>
<BR>
</SPAN></FONT><BLOCKQUOTE><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>On 11/22/2010 08:04 PM, Joe Hammerman wrote:<BR>
> Well we’re running DRBD in Primary – Primary mode, so the service should<BR>
> be enabled on both machines at the same time.<BR>
><BR>
> GFS breaks when DRBD loses sync, and both nodes become unusable, since<BR>
> neither can guarantee write integrity. If one of the nodes fenced, when<BR>
> it rebooted, it would become at the worst secondary. Then the node that<BR>
> never fenced stays on line, and we have %100 uptime.<BR>
><BR>
> This is a pretty non-standard setup, huh?<BR>
<BR>
But what's the point of two-node cluster if your setup cannot withstand<BR>
the loss of one node. In the case of sync loss, one node should be<BR>
fenced, so the other can keep on working with mounted GFS. Your goal<BR>
should be to achieve that.<BR>
<BR>
You should resolve it on DRBD level indeed, so when DRBD loses sync that<BR>
one node gets fenced... Something like:<BR>
<BR>
disk {<BR>
fencing resource-and-stonith;<BR>
}<BR>
handlers {<BR>
outdate-peer "/sbin/obliterate-peer.sh"; # We'll get back to this.<BR>
}<BR>
<BR>
You can get this script from:<BR>
<a href="http://people.redhat.com/lhh/obliterate-peer.sh">http://people.redhat.com/lhh/obliterate-peer.sh</a><BR>
<BR>
<BR>
Also please take a look at:<BR>
<a href="http://gfs.wikidev.net/DRBD_Cookbook">http://gfs.wikidev.net/DRBD_Cookbook</a><BR>
<BR>
<BR>
<BR>
I hope this helps!<BR>
<BR>
<BR>
<BR>
--<BR>
Jakov Sosic<BR>
_______________________________________________<BR>
drbd-user mailing list<BR>
<a href="drbd-user@lists.linbit.com">drbd-user@lists.linbit.com</a><BR>
<a href="http://lists.linbit.com/mailman/listinfo/drbd-user">http://lists.linbit.com/mailman/listinfo/drbd-user</a><BR>
<BR>
</SPAN></FONT></BLOCKQUOTE>
</BODY>
</HTML>