HP-UX System Administrator's Guide: Routine Management Tasks HP-UX 11i v3 (B3921-90023, September 2010)

distinguish between the two types of incremental backup. This is accomplished with
backup levels.
The file /var/adm/fbackupfiles/dates contains information about when the last
backup at each backup level was performed. This information is used by fbackup,
along with the modification date stamps on the files themselves, to determine when
files in the specified set are to be included with the backup that is currently being
created.
As previously stated, you can have up to 10 backup levels. When you run fbackup,
you can tell it which level to use. fbackup will use the level you give it as follows:
• Level 0 is always considered full backup.
• Higher levels are generally used to perform incremental backups.
• When doing an incremental backup of a particular graph (specified by a graph
file name), at a particular level, fbackup will search the file /var/adm/
fbackupfiles/dates to find the date of the most recent backup of the same
graph that was done at a lower level. If no such entry is found, the beginning of
time is assumed. All files in the specified graph that have been modified since this
date are back up.
Example of Setting Backup Levels
Assume you want the following three backup levels:
• Level 0 — full monthly backup
• Level 1 — weekly backup on Friday
• Level 2 — daily backup, except Friday
There are three ways you can implement these levels: use HP SMH, enter the fbackup
command and specify a backup level on the command line, or automate the commands
(see “Setting Up an Automated Backup Schedule” (page 132)).
The figure below illustrates the level numbers for implementing this example:
Date: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ... 1
Day: Su M T W Th Fr Sa Su M T W Th F Sa Su ...
Backup level 0 2 2 2 2 1 2 2 2 2 2 2 1 2 2 ... 0
If your data becomes corrupt on Thursday the 12th, do the following to restore your
system to its Wedneday the 11th state:
• Restore the monthly full backup tape from Sunday the 1st.
• Restore the weekly incremental backup tape from Friday the 6th.
• Restore the incremental backup tape from Wednesday the 11th.
For information about the actual method and commands to restore these tapes, see
“Restoring Your Data Using HP-UX Commands ” (page 138).
128 Managing Systems