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, Feb 15, 2011 at 12:23:10PM +0100, Roland Friedwagner wrote: > Hello, > > I stumbled over this one, when the firmware of a storage controller > on a drbd secondaryy gets upgraded and freezes io for about 1 minute. > Because drbd is the storage base of a kvm cluster (via iscsi) the > load of all guests goes up very high and all writing prozesses in > the guest freezes (thats pretty ok - i think;-) until io again flows > on upgraded controller. > > But what I've expected to happen is with ko-count set to 6 and timeout > is default of 6sec, that the primary will go to StandAlone mode after > 36 seconds. But this does _not_ happen :-O > > drbd.conf man page states: > ko-count number > In case the secondary node fails to complete a single write request > for count times the timeout, it is expelled from the cluster. > (I.e. the primary node goes into StandAlone mode.) > The default value is 0, which disables this feature. > > I prepared a test case and reproduce the same behavor by suspend > io via dmsetup on a secondary with a lvm backed backing device. > > So it looks like a bug? > (But maybe a missed something here ;-) Care to show logs + /proc/drbd, or the test case itself? -- : 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