HP-UX System Administrator's Guide: Routine Management Tasks

NOTE: As fbackup does its work, it will not back up files that are active (open) when
it encounters them. For this reason, it is best to back up your system when there are
few or no users logged in. If you can do so, you should change your system’s run-level
to the system administration state (single-user mode) before using fbackup. This will
insure that you are the only one logged in when the backup is run. As a result, a
minimum number of files will be active, thereby reducing the number of files that are
intended for, but not included in, the backup.
When changing to the single-user state, all the subdirectories are unmounted. Therefore,
you must remount them if necessary before backing up. For information about changing
to the single-user state, see shutdown(1M). If you shut down the system to single-user
state, mount the file systems (other than root (/)) that you want backed up.
General Procedure for Using the fbackup Command
To use the fbackup(1M) command:
1. Ensure that you have superuser capabilities.
2. Ensure that files you want to back up are not being accessed. The fbackup
command will not back up files that are active (opened) or locked.
3. Verify that the backup device is properly connected.
4. Verify that the backup device is turned on.
5. Load the backup device with write-enabled media. If the backup requires additional
media, fbackup will prompt you when to load or change media.
6. If possible, change to a single-user state. Then mount any directories you want to
back up.
7. Create the backup using fbackup. For example, the command
fbackup -f /dev/rmt/0m -i /home
can be used to back up the entire contents of /home to the device file
/dev/rmt/0m. For more information on fbackup, see fbackup(1M). For more
information on the /dev file formats, see the Configuring HP-UX for Peripherals
manual and see mt(7).
Creating the Index File on the Local Device
If you use the fbackup command, an index is written at the beginning of each tape
listing all files in the graph file being backed up. However, since this index is written
before the files are actually backed up, if a file is removed after the index is written but
before the file is backed up to tape (or something else happens that prevents the file
from being backed up), the index will not be completely accurate.
If you tell fbackup to make an online index file (using the -I option), it will create
the file after the backup is complete. Therefore, the only index that will be accurate is
Backing Up Data 131