PRIMECLUSTER Global File Services Configuration and Administration Guide 4.1 (Solaris(TM) 10 Operating System)

13.2.2 Backing-up entire file system

To backup the GFS Shared File System in file system unit, use dd(1M). The following describes the backing-up procedure using dd(1M).

For details about dd(1M), see the "Solaris X Reference Manual Collection".

Entire-file-system backing-up allows backing-up of the entire file system more quickly than file-by-file backing-up. However, a file system backed up with this method cannot be restored on a file-by-file basis during restoring.

Before executing backing-up, use the following procedure to check the partition information for the desired GFS Shared File System. Estimate the backing-up media capacity required for backing-up and the number of required media and then unmount of the GFS Shared File System.

• For a single partition configuration

Use sfcinfo(1M) to display partition information and check that the file system has only a single partition (same special file names) and that the capacity of the tape is sufficient. The size of the partition can be estimated by adding 1 megabyte to the sum of the values displayed in the size field (in kilobytes).

Example: In the following example, a file system with a single partition configuration is backed up.

# sfcinfo /dev/sfdsk/gfs01/dsk/volume01 <Enter>
FSID special                                      size  Type  mount
   1 /dev/sfdsk/gfs01/dsk/volume01(11500000021)        14422  META  -----
   1 /dev/sfdsk/gfs01/dsk/volume01(11500000021)         5116  LOG   -----
   1 /dev/sfdsk/gfs01/dsk/volume01(11500000021)        95112  DATA  -----
# dd if=/dev/sfdsk/gfs01/rdsk/volume01 of=/dev/rmt/0 bs=1024k <Enter>

• For a multi-partition configuration

dd(1M) can handle one partition at a time. For a multi-partition configuration, therefore, the partitions must be backed up one at a time. Use sfcinfo(1M) to check the partition configuration then backup each partition with the same procedure as used for a single partition configuration.

Example: In the following example, a file system with two partitions (file data area addition) is backed up.

# sfcinfo /dev/sfdsk/gfs01/dsk/volume01 <Enter>
FSID special                                      size  Type  mount
   1 /dev/sfdsk/gfs01/dsk/volume01(11500000021)        14422  META  -----
   1 /dev/sfdsk/gfs01/dsk/volume01(11500000021)         5116  LOG   -----
   1 /dev/sfdsk/gfs01/dsk/volume01(11500000021)        95112  DATA  -----
   1 /dev/sfdsk/gfs01/dsk/volume02(11500000022)        95112  DATA  -----
# dd if=/dev/sfdsk/gfs01/rdsk/volume01 of=/dev/rmt/0 bs=1024k <Enter>  -> Tape 1
  Tape change
# dd if=/dev/sfdsk/gfs01/rdsk/volume02 of=/dev/rmt/0 bs=1024k <Enter>  -> Tape 2

• All the partitions making up the desired GFS Shared File System must be backed up. Avoid backing-up and storing only some of the partitions.
• The tapes used for backups must be labeled so that the backed up partitions can be identified. They must then be stored as a set.

dd(1M) does not support multi-tape volumes. If the file system is too large to fit on a single tape, data needs to be divided and backed up. In such cases, set bs (block length) and count (number of blocks) and increase iseek (input-side offset (number of blocks) ) by the value of count.

Example: In the following example, a partition is backed up in 1 gigabyte units.

# dd if=/dev/sfdsk/gfs01/rdsk/volume01 of=/dev/rmt/0 bs=1024k count=1024 <Enter>  -> Tape 1
  Tape change
# dd if=/dev/sfdsk/gfs01/rdsk/volume01 of=/dev/rmt/0 bs=1024k count=1024 iseek=1024 <Enter>  -> Tape 2
  Tape change
# dd if=/dev/sfdsk/gfs01/rdsk/volume01 of=/dev/rmt/0 bs=1024k count=1024 iseek=2048 <Enter>  -> Tape 3
  Tape change
# dd if=/dev/sfdsk/gfs01/rdsk/volume01 of=/dev/rmt/0 bs=1024k count=1024 iseek=3072 <Enter>  -> Tape 4
  ...