Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Mon, Sep 6, 2010 at 8:48 PM, Lars Ellenberg <lars.ellenberg at linbit.com> wrote: > On Mon, Sep 06, 2010 at 08:34:40PM +0800, jan gestre wrote: >> Hi Everyone, >> >> I've found this drbddisk modification that will block takeover when >> the local resource is not in a safe state, however it only works if >> you only have one resource, but since I have two resources namely r0 >> and r1, it would not work. >> >> case "$CMD" in >> start) >> # forbid to become primary if ressource is not clean >> DRBDSTATEOK=`cat /proc/drbd | grep ' cs:Connected ' | grep ' >> ds:UpToDate/' | wc -l` >> if [ $DRBDSTATEOK -ne 1 ]; then >> echo >&2 "drbd is not in Connected/UpToDate state. refusing to >> start resource" >> exit 1 >> fi >> >> I would be truly grateful if anyone could care to show how to effect >> said modification. >> >> I'm trying to prevent a Split Brain scenario here, and I'm still >> testing my setup; I was in a predicament earlier wherein one of the >> resource r1 is in healthy state and r0 is in standalone >> Primary/Unknown state, I had to issue drdbadm -- --discard-my-data r0 >> to resolve the split brain. > > No Sir. > > What if the Primary dies? Hard? > You now want your Secondary to take over, no? > Well, you cannot anymore. Because it is not Connected. > How could it, you just lost the peer ;-) > > Don't focus only on one specific scenario. > Because, if you just "fix" that specific scenario, > you break a truckload of others. > > Maybe it helps a bit to read > http://www.mail-archive.com/pacemaker@oss.clusterlabs.org/msg04312.html > Thanks Lars, but now I am confused, maybe you can enlighten me, you're saying that I would be better off without modifying, what then would you recommend to prevent Split Brain? Add a stonith device, e.g. IBM RSA? Add handlers like dopd? BTW, I got the modification from this url --> http://lemonnier.se/erwan/blog/item/53/