As we know, snapshot of lv(logical volume) is the important technology implementation of data “backup”
and “recovery”. And now I use lvm
the result to deal with data.
But when I tested XFS or ext3 file system in the standalone LVM2 under Linux, found that if you want to use the snapshot
data, you must umount the original lv firstly and mount the snapshot volume to finish that.
Due to the cluster project, I use GFS as our storage solution, but when I do the following operations, it seems
that the lv and its snapshot can’t be mounted at the same time?
Is that any
Or if any file system can support this feature?
Any help will be appreciated.
OS: Linux FC2
(kernel upgraded to
Linux Cluster project: (DEVEL.1098174560 (built Oct 19 2004 16:30:29))
GFS: DEVEL.1098174560 (built Oct 19 2004 16:30:43)
create a vg as named “vg
# lvcreate -L
Logical volume "test2" created
# lvcreate -s -L
Logical volume "snap2" created
# gfs_mkfs -p lock_dlm -t cluster1:myfs -j 2 /dev/vg2/test2
This will destroy any data on /dev/vg2/test2.
Are you sure you want to proceed? [y/n] y
Filesystem Size: 2031440
Resource Groups: 32
Locking Protocol: lock_dlm
Lock Table: cluster1:myfs
# mount -t gfs /dev/vg2/test2 /home/test2
GFS: fsid=cluster1:myfs.0: Joined cluster. Now mounting FS...
GFS: fsid=cluster1:myfs.0: jid=0: Trying to acquire journal lock...
GFS: fsid=cluster1:myfs.0: jid=0: Looking at journal...
GFS: fsid=cluster1:myfs.0: jid=0: Done
GFS: fsid=cluster1:myfs.0: jid=1: Trying to acquire journal lock...
GFS: fsid=cluster1:myfs.0: jid=1: Looking at journal...
GFS: fsid=cluster1:myfs.0: jid=1: Done
# mount -t gfs /dev/vg2/snap2 /home/snap2
FAT: bogus number of reserved sectors
VFS: Can't find a valid FAT filesystem on dev dm-3.
GFS: not a GFS filesystem
mount: wrong fs type, bad option, bad superblock on /dev/vg2/snap2,
or too many mounted file systems