Example--Restoring a Bad Superblock
The following example shows how to restore the superblock copy 5264.
# newfs -N /dev/rdsk/c0t3d0s7 /dev/rdsk/c0t3d0s7: 163944 sectors in 506 cylinders of 9 tracks, 36 sectors 83.9MB in 32 cyl groups (16 c/g, 2.65MB/g, 1216 i/g) super-block backups (for fsck -b #) at: 32, 5264, 10496, 15728, 20960, 26192, 31424, 36656, 41888, 47120, 52352, 57584, 62816, 68048, 73280, 78512, 82976, 88208, 93440, 98672, 103904, 109136, 114368, 119600, 124832, 130064, 135296, 140528, 145760, 150992, 156224, 161456, # fsck -F ufs -o b=5264 /dev/rdsk/c0t3d0s7 Alternate superblock location: 5264. ** /dev/rdsk/c0t3d0s7 ** Last Mounted on ** Phase 1 - Check Blocks and Sizes ** Phase 2 - Check Pathnames ** Phase 3 - Check Connectivity ** Phase 4 - Check Reference Counts ** Phase 5 - Check Cyl groups 36 files, 867 used, 75712 free (16 frags, 9462 blocks, 0.0% fragmentation) /dev/rdsk/c0t3d0s7 FILE SYSTEM STATE SET TO OKAY ***** FILE SYSTEM WAS MODIFIED ***** # |
Syntax and Options for the fsck Command
The fsck command checks and repairs inconsistencies in file systems. If you run the fsck command without any options, it interactively asks for confirmation before making repairs. This command has four options:
Command and Option | Description |
|---|---|
fsck -m | Checks whether a file system can be mounted |
fsck -y | Assumes a yes response for all repairs |
fsck -n | Assumes a no response for all repairs |
fsck -o p | Noninteractively preens the file system, fixing all expected (innocuous) inconsistencies, but exits when a serious problem is encountered |