HP-UX Reference (11i v2 07/12) - 1M System Administration Commands A-M (vol 3)
f
fsck_vxfs(1M) fsck_vxfs(1M)
option from the command line as it can destroy a file system if not used correctly.
nolog Do not perform log replay. This option may be used if the log area was physically damaged.
Note: Use the -n option to verify whether there are file system inconsistencies. Use
fsck
-o full,nolog
to fix a corrupted file system and avoid a log replay. If you run
fsck
-o full
without nolog on a clean file system, it replays the intent log and performs a
full file system check.
p Allows parallel log replay for several VxFS file systems. Each message from
fsck is
prefixed with the device name to identify the device. This suboption does not perform a full
file system check in parallel; that is still done sequentially on each device, even when multi-
ple devices are specified. This option is compatible only with the
-y|-Y option (that is,
non-interactive full file system check), in which case a log replay is done in parallel on all
specified devices. A sequential full file system check is performed on devices where needed.
The number of devices that can be checked in parallel is determined by the amount of phy-
sical memory in the system. One instance of
fsck on a single device can consume up to a
maximum of 32 megabytes of memory.
Check a File System
A full check looks for the following inconsistencies:
• Blocks claimed by more than one inode or the free list.
• Blocks claimed by an inode outside the range of the file system.
• Incorrect link counts.
• Size checks:
− Incorrect number of blocks.
− Directory entry format.
• Bad inode 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.
Lost and Found Directory
Orphaned files and directories (allocated but unreferenced) are, with the user’s agreement, 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 file system’s root directory.
Notes
Checking the raw device is almost always faster.
Unlike 2.x and earlier releases of VxFS, a full file system check does not always perform pending extended
inode operations. Some extended operations can only be processed when the file system is mounted. A file
system that has been marked CLEAN can still contain extended operations.
If a structural flaw is detected during the intent log replay, the full fsck flag is set on the file system
without operator interaction.
If fsck encounters a large file on an older OS version, the command stops without completing the file sys-
tem check.
292 Hewlett-Packard Company − 2 − HP-UX 11i Version 2: December 2007 Update