On Sun, 6 Oct 2013 02:08:24 +0800 Gray Wen Wen <deutschland.g...@gmail.com> wrote: > Hi all, > now I am trying to configure a dual DRBD with mysql > i wanna use active/active mode without any loadbalance. > so my drbd is primary/primary on node1 and node2. > the mount point is /mysql > and i configure everything for mysql > then when I start the pacemaker service > the mysql can only be active on one node. > and another server show mysql startup error. > > I tried few times...so here is my question, > whether because of I set primay/primary drbd so actually the two > nodes hold the same shared storage (/mysql folder on two nodes) > so if one node start mysql that means it locks the folder /mysql > and another node can not continue use this shared storage. > > does mysql active/active mode must use loadblance or something else?
How do you think mysql (or any other database) works? What happens when a row is added to a table? Now think about making mysql sync that process (adding a row to a table) across several instances, regardless whether these are all read-write masters or some just read-only slaves. Yes, this can be made to work _if_ each mysql-instance has its own disk-space for the tables. But these mysql-instances will get horribly confused when someone else modifies their disk-space without them knowing. Even if that "someone else" is another mysql-instance meaning to do the right thing. There is a reason why the second instance sees the tables as "locked". Long story short: Don't do what you are trying to do. Either use drbd in active-passive and run _one_ mysql-instance on the drbd-master. Or run one mysql instance with its own disk-space on each node and promote/demote the write-master/read-only-slave with the mysql-RA. Good luck, Arnold
signature.asc
Description: PGP signature
_______________________________________________ Pacemaker mailing list: Pacemaker@oss.clusterlabs.org http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org
