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Moving files between snap trees, Backing up snapshots, Backups using ndmp – HP StoreAll Storage User Manual

Page 168: Backups without ndmp, Backups with the tar utility

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Moving files between snap trees

Files created on, copied, or moved to a snap tree directory can be moved to any other snap tree
or non-snap tree directory on the same file system, provided they are not snapped. After a snapshot
is taken and the files have become part of that snapshot, they cannot be moved to any other snap
tree or directory on the same file system. However, the files can be moved to any snap tree or
directory on a different file system.

Backing up snapshots

Snapshots are stored in a .snapshot directory under the directory tree. For example:

# ls -alR /fs2/dir.tst
/fs2/dir.tst:
drwxr-xr-x 4 root root 4096 Feb 8 09:11 dir.dir
-rwxr-xr-x 1 root root 99999999 Jan 31 09:33 file.0
-rwxr-xr-x 1 root root 99999999 Jan 31 09:33 file.1
drwxr-xr-x 2 root root 4096 Apr 6 15:55 .snapshot
/fs2/dir.tst/.snapshot:
lrwxrwxrwx 1 root root 15 Apr 6 15:39 2011-04-06T15:39:57_ -> ../.@1302118797
lrwxrwxrwx 1 root root 15 Apr 6 15:55 2011-04-06T15:55:07_tst1 -> ../.@1302119707 /fs2/dir.tst/dir.dir: -rwxr-xr-x
1 root root 99999999 Jan 31 09:34 file.1

NOTE:

The links beginning with .@ are used internally by the snapshot software and cannot be

accessed.

To back up the snapshots, use the procedure corresponding to your backup method.

Backups using NDMP

By default, NDMP does not back up the .snapshot directory. For example, if you specify a
backup of the /fs2/dir.test directory, NDMP backs up the directory but excludes /fs2/
dir.tst/.snapshot

and its contents.

To back up the snapshot of the directory , specify the path /fs2/dir.tst/.snapshot/
2011-04-06T15:55:07_tst1

. Now you can use the snapshot ( a point in time copy) to restore

its associated directory. For example use /fs2/dir.tst/.snapshot/
2011-04-06T15:55:07_tst1

to restore /fs2/dir.tst.

Backups without NDMP

DMA applications can not backup a snapshot directory tree using a path such as /fs2/dir.tst/
.snapshot/time-stamp-name

. Instead, mount the snapshot using the mount -o bind option

and then back up the mount point. For example, using a mount point such as as
/mnt-time_stamp-name

, use the following command to mount the snapshot:

mount –o bind /fs2/dir.tst.snapshot/time-stamp-name /mnt-time_stamp-name

Then configure the DMA to back up /mnt-time_stamp-name.

Backups with the tar utility

The tar symbolic link (h) option can copy snapshots. For example, the following command copies
the /snapfs1/test3 directory associated with the point-in-time snapshot.

tar –cvfh /snapfs1/test3/.snapshot/2011-07-01T044500_hourly

168 Creating X9000 software snapshots