Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On 10/26/2010 11:20 PM, 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 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' Hi, what are the options you try and mount the snapshot? mount should not assume a "drbd" filesystem type. You probably use bad options or have a faulty fstab. If all else fails, use mount -t <correct_fs>. Also, your filesystem should have been created after create-md, on the /dev/drbdX device (unless I'm gravely mistaken). In any case, the fs has no notion of DRBD whatsoever, as DRBD works on the block layer of things. HTH, Felix