NAME
fsck (vxfs) — check and repair a VxFS file system
SYNOPSIS
/usr/sbin/fsck
[-F
vxfs]
[-V]
[-pPmnNyY]
[-o
full,nolog]
[special... ]
DESCRIPTION
The
fsck
utility checks VxFS file systems for consistency.
Since VxFS records pending file system updates in an intent log,
fsck
typically runs an intent log replay, rather than a full structural file
system check on a VxFS file system.
If
special
is not specified,
fsck
reads the table in
/etc/fstab,
using the first field to determine which file system to check.
Options
- -F vxfs
Specify the VxFS file system type.
- -V
Echo the completed command line, but performs no other action.
The command line is generated by incorporating
the user specified options and other information derived from
/etc/fstab.
This option allows the user to verify the command line.
- -y|Y
Assume a "yes" response to all questions asked by
fsck.
Additionally, if the file system requires a full file system check
after the log replay, or if the
nolog
suboption causes the log replay to be skipped and the file system is not clean,
then a full file system check is performed.
- -m
Check whether or not the file system is marked clean.
This option does not validate the file system.
If the file system is corrupt for some reason, a subsequent mount may
fail and a full
fsck
may be required to clean it.
fsck -n
may be used to test for file system corruption.
- -n|N
Assume a "no" response to all questions asked by
fsck;
do not open the file system for writing. Log replay is not performed.
A full file system check is performed.
- -p
Cause
fsck
to produce messages that identify the device being checked.
- -P
With VxFS,
-P
is used by
fsck
by default; it does not provide any functionality.
With other file system types,
-P
may be used for optional functionality.
- -o
Specify VxFS file system specific options.
These options can be a combination of the following in a comma-separated list:
- full
Perform a full file system check. The default is to perform
an intent log replay only.
Since the VxFS file system maintains an intent log, a complete check is
generally not required.
If the file system detects damage
or the log replay operation detects damage, an indication
that a complete check is required is placed in the super-block,
and a full check is performed.
- nolog
Do not perform log replay. This option may be used if the log area
was physically damaged.
When a full check is performed, the following inconsistencies are checked:
Blocks claimed by more than one inode or the free list.
Blocks claimed by an inode outside the range of the file system.
Size checks:
- -
Incorrect number of blocks.
- -
Directory entry format.
Blocks not accounted for anywhere.
Directory checks:
- -
File pointing to unallocated inode.
- -
Inode number out of range.
- -
Linkage to parent directory.
- -
Hash chain linkage.
- -
Free space count.
Super-block checks:
- -
Checksum mismatch.
- -
More blocks for inodes than there are in the file system.
Structural Files:
- -
Fileset headers.
- -
Object Location Table (OLT).
- -
Inode list files.
- -
Inode allocation summary files.
- -
Attribute files (including Access Control Lists).
- -
Attribute link counts.
Bad free block list format.
Total free block and/or free inode count incorrect.
Orphaned files and directories (allocated but unreferenced) are,
with the user's concurrence, reconnected by
placing them in the
lost+found
directory.
The name assigned is the inode number.
The only restriction
is that the directory
lost+found
must already exist
in the root of the file system being checked.
OUTPUT
Structural errors discovered during a full check are displayed on
standard output. Responses required during a full check are read from
standard input.
The following return codes are used for the
-m
(generic)
option for all devices other than the one used by the root file system:
- 0
The file system is unmounted and clean.
- 32
The file system is unmounted and needs checking.
- 33
The file system is mounted.
- 34
The stat of the device failed.
- Other
The state could not be determined because of an error.
The following return codes are used for the
-m
(generic)
option for the device used by the root file system:
- 0
The root file system is mounted read-only and is clean, or
the root file system is mounted read/write and therefore
doesn't need checking.
- 32
The root file system is mounted read-only and needs checking.
- 34
The stat of the device failed.
- Other
The state could not be determined because of an error.
ERROR/DIAGNOSTICS
All error messages that relate to the contents of a file
system produced during a log replay are displayed on standard output.
All I/O failures and exit messages are displayed on standard error output.
NOTES
Checking the raw device is almost always faster.
A full file-system check will always perform any pending extended-inode operations,
generating various messages, without operator interaction.
If a structural flaw is detected, the
VX_FULLFSCK
flag will be set on the file system, without operator interaction.
If
fsck
was not invoked with the
-y
option,
it must be reinvoked with the
-y
or
-o full
option to perform a full
fsck.
If the
-o full
flag is used on a clean file system,
fsck
will perform a log replay first,
and since the
VX_FULLFSCK
flag is set, it will not update the inode and extent maps
before performing the full
fsck,
so it will report inconsistencies. Use the
-n
option to verify file-system inconsistency.
FILES
- /etc/fstab
Default list of file systems to check.
