Use the procedures in this section to collect bootstrap and disk configuration information necessary to perform a disaster recovery.
During each scheduled backup of the backup server, Backup creates a special save set named bootstrap, essential to perform a successful disaster recovery. The bootstrap contains the Backup server file index, media database, and configuration files.
Backup does not save the bootstrap information during a manual backup; Backup only saves it during a scheduled save.
Backup prints or saves to a file the most recent bootstrap information that includes dates, locations, and save set ID numbers. See Example 1-1 for an example of the bootstrap information generated each time Backup performs a schedules backup. Make sure you store the bootstrap printout or electronic file in a safe place.
The bootstrap displays a listing of the bootstrap save sets backed up for the past month. For example:
August 20 03:30 1996 Backup bootstrap information Page 1 date time level ssid file record volume 8/19/96 2:29:08 9 1148868949 56 0 mars.005 8/20/96 2:52:25 9 1148868985 77 0 mars.001 |
You can also perform scheduled backups of the Backup server indexes by using the savegrp command. Using this command also sends the bootstrap information to a printer or electronic file. For example:
# savegrp -O -c server-name |
To use the savegrp -O command, you must be root on the Backup server.
For information about printing or saving bootstrap data to a file, refer to the Solstice Backup 5.1 Administratioin Guide.
The most efficient way to recover the bootstrap is to make sure you save the bootstrap information prior to a disaster. However, if you do not have the information, you must scan the most recent backup volume to find the save set ID (save set ID or ssid) of the most recent bootstrap. Use the scanner -B command because it always finds a valid bootstrap.
After you locate the bootstrap with the most recent date, run the mmrecov command, and supply the save set ID and file number displayed by the scanner command
Use the following steps to find the most recent save set ID:
Place the most recent media used for scheduled backups in the server device.
At the system prompt, change to the directory where you originally installed Backup, typically, /usr/sbin/nsr.
Use the scanner -B command to locate the most recent bootstrap on the media, for example:
# /usr/sbin/nsr/scanner -B /dev/rmt/0hbn |
The scanner -B command displays the latest bootstrap save set information found on the backup volume, as illustrated below:
scanner: scanning 8mm tape jupiter.001 /dev/rmt/0hbn scanner: Bootstrap 1148869870 of 8/21/96 7:45:15 located on volume jupiter.001, file 88 |
An additional precautionary step to help you recover from loss of critical data: before a disaster strikes is to find out how each disk on your network is partitioned and formatted and print and save this information. If a disk is damaged or destroyed during a disaster, use the disk information to recreate the disk exactly as it was prior to the disk crash. Do the same for each system Backup backs up, unless the systems are consistent in disk and filesystem layout.
When you recreate your disk configuration, you need to have partitions large enough to hold all the recovered data. Make the partitions at least as large as they were before to the crash.
Use the df command to find out how the Backup server disks are partitioned and mounted. Use the appropriate operating system command to print disk partitioning information. Do the same for any Backup clients that have local hard disks.
For example, the df -k information looks similar to this:
Filesystem kbytes used avail capacity Mounted on /dev/dsk/c0t3d0s0 865678 624020 155098 80% / /dev/dsk/c0t1d0s6 265807 198729 40498 83% /usr /dev/dsk/c0t1d0s4 96103 57468 29025 66% /var swap 107756 8 107748 0% /tmp |
The following dkinfo command examples give you information about how each disk is partitioned for a SunOS system:
The prtvtoc command example in Example 1-2 provides you information about how each disk is partitioned for a Solaris system. The device name is the "raw" device corresponding to the device name used for the output from the df command.
* /dev/dsk/c0t1d0s3 partition map * * Dimensions: * 512 bytes/sector * 80 sectors/track * 17 tracks/cylinder * 1360 sectors/cylinder * 3500 cylinders * 1965 accessible cylinders * * Flags: * 1: unmountable * 10: read-only * * First Sector Last * Partition Tag Flags Sector Count Sector Mount Directory 2 5 00 0 2672400 2672399 3 6 00 0 1434800 1434799 /export 4 7 00 1434800 205360 1640159 /var 5 6 00 1640160 463760 2103919 /opt 6 4 00 2103920 568480 2672399 /usr |
If a disk is damaged, you can restore it and recover the filesystems to their original state, using the hardcopy information from these disk information commands.