Backups Under HP

Backing up and restoring LVM group configurations

If Logical Volume Management (LVM) is running, backups must be made of the configuration files for each volume group. If the configuration of the disk or the logical volume in a volume group is changed, the vgcfgbackup command runs automatically and saves the configuration of each volume group. This is crucial because each volume group configuration is unique and does not begin or end at a fixed location on a disk.

By default vgcfgbackup saves the configuration to /etc/lvmconf/volume_group_name.conf. However, the information can be saved to a different file if vgcfgbackup is run from the command line. The syntax is as follows:

vgcfgbackup -f filename volume_group_name

LVM configurations can be restored with the vgcfgrestore command. Before this command is run, the volume group needs to be deactivated using vgchange.

fbackup and frecover

frecover and fbackup work together like backup and restore. frecover cannot be used to recover data from a tape created with another utility. Additionally, the only types of QIC tapes supported by frecover and fbackup are QIC-25 and QIC-1000.

The /var/adm/fbackupfiles/dates files contains information on the last backup at each level was created. fbackup searches this file to determine which incremental needs to be done. If no record of an incremental or full backup is found, fbackup will perform a full backup. The date in /var/adm/fbackupfiles/dates is updated by fbackup only if it is used with the -u option.

fbackup can be called from the command line.

fbackup -f /dev/rmt/0m -i /home This backs up all of /home to the device file /dev/rmt/0m.

Note: When using fbackup and frecover with HP format cartridge tapes the output from the command must be piped through tcio. This saves the cartridge drive from excessive wear which can cause it to fail. tcio should not be used with QIC or DDS format DAT tapes.

More than one device can be specified with fbackup. If two devices are specified, the second one is used when the media in the first one fills up. When backing up NFS mounted files, fbackup must be run by the superuser to back up file which do not have world read permissions. fbackup can be used with the -I option to create an index on the local device.

The frecover follows the same syntax as fbackup. Among the options it supports are the following:

• -I To list the contents of the index.
• -r To recover all the files from a backup.
• -x To recover individual files from a backup.

The advantages and disadvantages of fbackup and frecover include:

• Multiple files cannot be appended to the same backup tape.
• Multiple independent backups cannot be performed on the same tape as fbackup rewinds the tape.
• It is relatively easy to list the files on a tape.
• The backup can be verified.
• Files can be listed as they are backed up or restored.
• Wildcards cannot be used when restoring files.
• There is no interactive way to select files for recovery.

Tips and Quirks

Note: The HP file system layout changed a great deal in HP-UX 10.0. Due to these changes only "user" files and directories created under HP-UX releases prior to 10.0 can be recovered under 10.0. Structural files, such as /usr and /bin cannot.

HP backups can also be created using SAM.

Under HP-UX a bootable tape can be created. For HP-UX 9.X, the mkrs utility is used to do this. Under 10.X the copyutil is used.