Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
> On Tue, Jun 01, 2010 at 05:47:34PM +0200, Florian Haas wrote: >> On 2010-06-01 15:17, Caspar Smit wrote: >> > I tested the following situation: >> > >> > - I pulled out BOTH sdb and sdc on node 1. >> > - Did a write action on the iscsitarget from a client machine. >> > - DRBD (on-io-error detach) detached the primary node 1 and became: >> > Primary/Secondary - Diskless/UpToDate >> > - The performance degraded significantly after it became diskless. >> > >> > Is it possible for the Linbit OCF RA script to detect that a low level >> IO >> > error occured on the DRBD backed storage (md0)? >> > >> > What I would like is that in a case of low level failure (software >> raid >> > failure) that a failover takes place and node 2 becomes the primary >> > because now that doesn't happen. >> >> It doesn't hurt to peruse the documentation. :) >> >> http://www.drbd.org/users-guide/s-handling-disk-errors.html >> http://www.drbd.org/users-guide/s-configure-io-error-behavior.html >> >> If you use a local-io-error handler that simply does >> "echo o > /proc/sysrq-trigger", then in case of an I/O error the node >> will remove itself from the cluster and Pacemaker will initiate >> failover. > > That may be a bit brutal, but should of course work. > > The less brutal way would use the preference scores. > The monitor action of ocf:linbit:drbd does adjust its master score > based on various things, also on the local disk state. > > If the local disk state is not UpToDate, the master score will be <= 10, > if the local disk is UpToDate and we are connected, it will be 10000. > > So unless you have other scores that weight more, > I expect the PE to decide that moving the resources > over would be a good idea. The Policy Engine is one part that is a little fuzzy to me. I entered node 1 as preferred master so I guess that is the reason the PE doesn't decide to failover. location ms-drbd0-master-on-node1 ms-drbd0 \ rule $id="ms-drbd0-master-on-node1-rule" $role="master" 100: #uname eq node1 So do I need to adjust this constraint to let it failover? Thanks for the help, Caspar Smit > > > -- > : Lars Ellenberg > : LINBIT | Your Way to High Availability > : DRBD/HA support and consulting http://www.linbit.com > > DRBD® and LINBIT® are registered trademarks of LINBIT, Austria. > __ > please don't Cc me, but send to list -- I'm subscribed > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user >