Occasionally, a file system becomes so damaged that you must completely restore it. Typically, you need to restore a complete file system after a disk failure. You might need to replace the hardware before you can restore the software. For information on how to replace a disk, see Chapter 34, SPARC: Adding a Disk (Tasks) or Chapter 35, x86: Adding a Disk (Tasks).
Full restoration of a file system such as /export/home can take a lot of time. If you have consistently backed up file systems, you can restore them to their state from the time of the last incremental backup.
You cannot use this procedure to restore the root (/) or /usr file systems. For instructions on restoring these file systems, see How to Restore the root (/) and /usr File Systems.
If necessary, unmount the file system.
# umount /dev/rdsk/device-name |
Or:
# umount /file-system |
Create the new file system.
# newfs /dev/rdsk/device-name |
You are asked if you want to construct a new file system on the raw device. Verify that the device-name is correct so that you don't destroy the wrong file system.
For more information, see the newfs(1M) man page.
Confirm that the new file system should be created.
newfs: construct a new file system /dev/rdsk/cwtxdysz:(y/n)? y |
The new file system is created.
Mount the new file system on a temporary mount point.
# mount /dev/dsk/device-name /mnt |
Change to the mount point directory.
# cd /mnt |
(Optional) Write-protect the tapes for safety.
Insert the first volume of the level 0 tape into the tape drive.
Restore the files.
# ufsrestore rvf /dev/rmt/n |
The dump level 0 backup is restored. If the backup required multiple tapes, you are prompted to load each tape in numeric order.
Remove the tape and load the next level tape in the drive.
Always restore tapes starting with dump level 0 and continuing until you reach the highest dump level.
Repeat Step 8 through Step 10 for each dump level, from the lowest to the highest level.
Verify that the file system is restored.
# ls |
Remove the restoresymtable file.
# rm restoresymtable |
The restoresymtable file that is created and used by the ufsrestore command to check-point the restore is removed.
Change to another directory.
# cd / |
Unmount the newly restored file system.
# umount /mnt |
Remove the last tape and insert a new tape that is not write-protected in the tape drive.
Make a level 0 backup of the newly restored file system.
# ufsdump 0ucf /dev/rmt/n /dev/rdsk/device-name |
A level 0 backup is performed. Always immediately do a full backup of a newly created file system because the ufsrestore command repositions the files and changes the inode allocation.
Mount the restored file system.
# mount /dev/dsk/device-name mount-point |
The restored file system is mounted and available for use.
Verify that the restored and mounted file system is available.
# ls mount-point |
The following example shows how to restore the /export/home file system.
# umount /export/home # newfs /dev/rdsk/c0t0d0s7 newfs: /dev/rdsk/c0t0d0s7 last mounted as /export/home newfs: construct a new file system /dev/rdsk/c0t0d0s7: (y/n)? y 819314 sectors in 867 cylinders of 15 tracks, 63 sectors 400.1MB in 55 cyl groups (16 c/g, 7.38MB/g, 3584 i/g) super-block backups (for fsck -F ufs -o b=#) at: 32, 15216, 30400, 45584, 60768, 75952, 91136, 106320, 121504, 136688, 681264, 696448, 711632, 725792, 740976, 756160, 771344, 786528, 801712, 816896, Verify volume and initialize maps Media block size is 126 Dump date: Tue Oct 07 08:41:41 2003 Dumped from: the epoch Level 0 dump of a partial file system on starbug:/export/home/kryten Label: none Begin level 0 restore Initialize symbol table. Extract directories from tape Calculate extraction list. Extract new leaves. Check pointing the restore extract file ./export/home/kryten/filea extract file ./export/home/kryten/fileb extract file ./export/home/kryten/filec extract file ./export/home/kryten/letters/letter1 extract file ./export/home/kryten/letters/letter2 extract file ./export/home/kryten/letters/letter3 extract file ./export/home/kryten/reports/reportA extract file ./export/home/kryten/reports/reportB extract file ./export/home/kryten/reports/reportC Add links Set directory mode, owner, and times. Check the symbol table. Check pointing the restore # mount /dev/dsk/c0t0d0s7 /mnt # cd /mnt # ufsrestore rvf /dev/rmt/0 # ls # rm restoresymtable # cd / # umount /mnt # ufsdump 0ucf /dev/rmt/0 /export/home . . . # mount /dev/dsk/c0t3d0s7 /export/home # ls /export/home |