25.10.2012 19:55, Whit Blauvelt wrote: > On Thu, Oct 25, 2012 at 12:34:40PM -0400, Whit Blauvelt wrote: > >> The easy road appears to be blocked, though. with this edited XML: >> >> <disk type='block' device='disk'> >> <driver name='qemu' type='raw'/> >> <source dev='/dev/drbd/by-res/sql'/> >> <target dev='hda' bus='ide'/> >> <address type='drive' controller='0' bus='0' target='0' unit='0'/> >> </disk> >> >> the result is: >> >> # virsh start sql >> error: Failed to start domain sql >> error: unable to open disk path /dev/drbd/by-res/sql: Wrong medium type >> >> This is with virsh 0.9.12. Also fails when skipping the symlink: <source >> dev='/dev/drbd12'/> >> leads to exactly the same failure. Either I'm missing another tweak, or this >> setup isn't currently compatible. > > Do I have to do something crazy like stack another LVM volume group on top > of DRBD, then put a logical volume in that, then clone the VM onto the top > of that? So:
I use it with corosync, pacemaker, dlm and clvmd. > > VM > LV > VG this ^ one is clustered in my case, so I activate individual volumes on different hosts. drbd should be in active-active mode for this. I need this anyways for live VM migrations. > DRBD > LV > VG > DISK > > or should it work to have just > > VM > DRBD > LV > VG > DISK This one should be safer (i.e. active-passive setup is sufficient to spread VM load across hosts), but live migrations do not work and configuration overhead is bigger. If you need live migrations, then you need active-active setup with proper fencing. And then you can go either way. > > as I'm currently attempting, if I just tweak some other aspect here? For > clarity, the scheme is to have a 1-to-1 correspondence between each VM and > its backing DRBD instance, so that the DRBD primary assignment is atomic, > and can be switched per VM between the two hosts. > > Whit > _______________________________________________ > drbd-user mailing list > drbd-user@lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user > _______________________________________________ drbd-user mailing list drbd-user@lists.linbit.com http://lists.linbit.com/mailman/listinfo/drbd-user
