fsck Command – Check & Repair Linux & Unix File Systems

Phase 1: check blocks and sizes

fsck error messages, warning messages and responses for Phase 1 – check blocks and sizes phase.
The message gives a yes/no option to fix or not to fix the problem . Pressing no cause fsck to ignore and continue past the error

1.1) UNKNOWN FILE TYPE I=(CLEAR)

The the inode number s not recognized as special block , character , regular, symbolic link, FIFO file or directory inode.

YES , response to clear prompt reallocates inode by zeroing out its contents and causes UNALLOCATED error message in Phase 2 for directory entries pointing to this inode

NO –  cause fsck to ignore and continue past the error

1.2) PARTIALLY TRUNCATED the inode number =(SALVAGE)

If a system crashes while truncating a file then fsck finds inode size as shorter than the number of blocks allocated to it. fsck is asking to complete the truncation to the specified size .

YES , response to the SALVAGE prompt complete the truncation for the inode number .

NO – causes fsck to ignore and continue past the error .

1.3) LINK COUNT TABLE OVERFLOW (CONTINUE)

fsck maintains an internal table containing allocated inodes with a link count of zero. This internal table has become full with entries and can’t accommodate more entries .

YES , responses to the CONTINUE prompt causes fsck to continue with the fsck. File system is not checked completely and a second run should be made to recheck file system again . If another allocated inode with a zero link count is found, the error message is repeated. again .

No – response terminate the fsck process.

1.4) B BAD I=

The inode number contains block number B with a number lower than the number of the first data block in the
file system or greater than the number of the last block in the filesystem. This error condition might generate the EXCESSIVE BAD BLKS error message in Phase 1 if the inode number has too many block numbers outside the
file system range. This error condition generates the BAD/DUP error messages in Phases 2 and 4.

1.5) EXCESSIVE BAD BLKS I=(CONTINUE)

There are more than 10  blocks with a number lower than the number of the first data block in the
file system or greater than the number of the last block in the file system associated with the inode number .

Possible responses to the CONTINUE prompt are:

Ignore –  the rest of the blocks in this inode and continue checking with the next the inode number n the filesystem. This error condition skips the error in the file system so a second run of fsck should be made to recheck this filesystem.

No – Terminate the fsck program leaving file system with errors.

1.6) BAD STATE DDD TO BLKERR

An internal error has caused the fsck’s state map to have the impossible value DDD.
fsck exits immediately. Run fsck multiple times if this happens.

1.7) B DUP I=

the inode number contains block number B that is already claimed by another inode. This error condition might generate the EXCESSIVE DUP BLKS error message in Phase 1 if the inode number has too many block numbers claimed by other inodes. This error condition invokes Phase 1B and generates the BAD/DUP error message in Phases 2 and 4.

1.8) BAD MODE: MAKE IT A FILE?

This message is generated when the status of a given the inode number s set to all ones, indicating
file system damage. This message does not indicate disk damage, unless it appears repeatedly after fsck -y has been run. A response of y causes fsck to reinitialize the inode to a reasonable value.

1.9) EXCESSIVE DUP BLKS I=(CONTINUE)

There are too many (usually more than 10) blocks claimed by other inodes.

Possible responses to the CONTINUE prompt are:

Ignore – the rest of the blocks in this inode and continue checking with the next the inode number n the filesystem. This error condition prevents a complete check of the filesystem. A second run of fsck should be made to recheck the
filesystem.

NO – Terminate the fsck program. File system errors are not fixed and fsck has to be run again.

1.10) DUP TABLE OVERFLOW (CONTINUE)

An internal table in fsck containing duplicate block numbers has no more room.

Possible responses to the CONTINUE prompt are:

Continue –  with the program. This error condition prevents a complete check of the
file system. A second run of fsck should be made to recheck the file system. If another duplicate block is found, this error message repeats.

No, Terminate the fsck program. File system errors are not fixed and fsck has to be run again.

1.11) PARTIALLY ALLOCATED the inode number =(CLEAR)

the inode number is neither allocated nor unallocated.

Possible responses to the CLEAR prompt are:

Deallocate , the inode number by zeroing out its contents.

Ignore – ignore this error condition. File system errors are not fixed and fsck has to be run again.

1.12) INCORRECT BLOCK COUNT I=(X should be Y) (CORRECT)

The block count for the inode number is X blocks, but should be Y blocks. When preening, the count is corrected.

Possible responses to the CORRECT prompt are:

Replace the block count of the inode number by Y.

Ignore this error condition, File system errors are not fixed and fsck has to be run again.

1.13) B DUP I=I

When a duplicate block is found in the filesystem, the file system is rescanned to find the inode that previously claimed that block. When the duplicate block is found, the following informational message appears:
the inode number contains block number B that is already claimed by another inode. This error condition generates the BAD/DUP error message in Phase 2. You can determine which inodes have overlapping blocks by examining this error condition and the DUP error condition in Phase 1.

Initialization Phase
** phase 1 – Check Blocks and Sizes
NEXT>>
** phase 2 – Check Pathnames
** phase 3 – Check Connectivity
** phase 4 – Check Reference Counts
** phase 5 – Check Cylinder Groups
cleanup phase