Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Wed, Dec 19, 2007 at 04:05:04PM +0100, Martin Gombac wrote: > >>How do you prevent the other node from trying to come and and > >>creating a > >>split brain situation? > > > >use the drbd-outdate-peer handler and configure dopd. > >yes, it has some issues as well, I know. we fixed some of those only > >last week. as long as you don't use too many drbd, it should work > >reliably enough with heartbeat 2.1.2. > >make sure you configure a timeout (the default timeout is 60seconds, > >which is longer than several other timeouts and causes cascading > >timeout > >trouble), in short: > > outdate-peer "/usr/lib/heartbeat/drbd-peer-outdater -t 5"; > .... and have downtime for half of your services when you take > problematic node offline. hey, you asked how to improve on avoiding split brain. but also see the other mail. > >>How do you get alerted that the sync is broken? > > > >nagios pages you? > Nagios is cool, i use it, but probably won't help you with crossover > link. Altho there is nagios-nrpe which probably with custom plugins > would allow you to monitor it. In case you do write your own plugin > for this, forward it to me. ;-) monitor the state of drbd. anything looking like an ongoing resync is a warning. anything not "Connected", and not in the above resync category is critical. > >>How do you recover? > > > >fix the replication link. > >reconnect drbd, if it does not do so by itself. > Take the server offline and services that are on it with it. Fix it. > Bring it back. Be quick at it tho. Try to explain to the costumer why > the other node can't take over the resources even thou you sold them > fail-over clustered install. see my other mail. if your replication link is a spof, you have a spof. eliminate it. -- : Lars Ellenberg http://www.linbit.com : : DRBD/HA support and consulting sales at linbit.com : : LINBIT Information Technologies GmbH Tel +43-1-8178292-0 : : Vivenotgasse 48, A-1120 Vienna/Europe Fax +43-1-8178292-82 : __ please use the "List-Reply" function of your email client.