Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Sorry to reopen a post so old, but looks like our problem, but what is said in the post is not true for us. mount-t ext4-o your, favorite, mount, options / dev / $ vg / $ snap_lv / mnt / point or mount-t ext3-o your, favorite, mount, options / dev / $ vg / $ snap_lv / mnt / point Produces the same effect: mount: unknown filesystem type 'drbd' We tested all scenarios. DRBD active Off (after restarting the machine) Desolate. On both machines, Primary and Secondary, both LV is corrupt and can not boot the system containing. On both machines, we can do even a fsck or mount the disks to make use of the data (Such rsync) in the new KVM we are installing to restore this great disaster. http://www.gossamer-threads.com/lists/drbd/users/24875 Certainly we are desperate. DRBD 8.3.13-0 We just want to at this stage of the impact, to mount the LV in the system (Proxmox 2.2), and to make certain things rsync after restoration we are doing missing from the backup. Lars Ellenberg wrote > On Tue, Oct 26, 2010 at 04:20:40PM -0500, Lewis Donzis wrote: >> We'd like to be able to make backups from our DRBD secondary by mounting >> the underlying filesystems. After some searching, this appears to be a >> relatively common discussion: running DRBD on top of LVM, making a >> snapshow of the backing LV on the secondary, and mounting the snapshot >> LV. >> As has been discussed, it's not perfect, but it should produce reasonable >> results most of the time, at least no worse than if there had been a >> power >> failure. >> >> So, I'm sorry if this is a silly question, but I can't seem to get this >> to >> work. It appears that DRBD permanently prevents mounting the backing >> device (or its snapshot) because "drbdadm create-md" function modifies >> the >> filesystem > > Nope. > It modifies the block device. > >> so that it can no longer be mounted except via the /dev/drbdX >> device. >> >> In particular, attempting to mount a snapshot, or detaching DRBD >> from the backing device and attempting to mount the file system, or even >> just attempting to mount the backing device after create-md has run, >> results in: >> >> mount: unknown filesystem type 'drbd' > > how about > mount -t ext4 -o your,favorite,mount,options /dev/$vg/$snap_lv /mnt/point > (or ext3 or xfs or whatever it is you are actually using?) > > -- > : 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 .linbit > http://lists.linbit.com/mailman/listinfo/drbd-user Lars Ellenberg wrote > On Tue, Oct 26, 2010 at 04:20:40PM -0500, Lewis Donzis wrote: >> We'd like to be able to make backups from our DRBD secondary by mounting >> the underlying filesystems. After some searching, this appears to be a >> relatively common discussion: running DRBD on top of LVM, making a >> snapshow of the backing LV on the secondary, and mounting the snapshot >> LV. >> As has been discussed, it's not perfect, but it should produce reasonable >> results most of the time, at least no worse than if there had been a >> power >> failure. >> >> So, I'm sorry if this is a silly question, but I can't seem to get this >> to >> work. It appears that DRBD permanently prevents mounting the backing >> device (or its snapshot) because "drbdadm create-md" function modifies >> the >> filesystem > > Nope. > It modifies the block device. > >> so that it can no longer be mounted except via the /dev/drbdX >> device. >> >> In particular, attempting to mount a snapshot, or detaching DRBD >> from the backing device and attempting to mount the file system, or even >> just attempting to mount the backing device after create-md has run, >> results in: >> >> mount: unknown filesystem type 'drbd' > > how about > mount -t ext4 -o your,favorite,mount,options /dev/$vg/$snap_lv /mnt/point > (or ext3 or xfs or whatever it is you are actually using?) > > -- > : 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 .linbit > http://lists.linbit.com/mailman/listinfo/drbd-user -- View this message in context: http://drbd.10923.n7.nabble.com/Problem-mounting-lvm-snapshot-tp14216p17268.html Sent from the DRBD - User mailing list archive at Nabble.com.