Open System Services Management and Operations Guide (G06.30+, H06.08+, J06.03+)

Table 11 Inconsistencies Checked by FSCK (continued)
ExplanationTypeInconsistency
and only major inconsistencies are being corrected, FSCK does
not create a new catalog but does:
• Reset the mounted flag to zero.
• Clear the bitmap of inconsistencies reported by an OSS name
server.
• Add any lost inode numbers to the appropriate free list.
An OSS name server maintains two free-inode lists in each catalog.
One is used to list the inodes that can be immediately reused. The
SeriousBad free-inode list
other is used to list those inodes that can be reused only after a
successful unmount and mount sequence. The FSCK utility detects
and corrects the following inconsistencies:
• An inode other than a free-inode block appears on a free-inode
list.
• A loop occurs in a free-inode list.
• An in-use inode also appears in a free-inode block.
• The same free-inode block appears on both free-inode lists.
If any free-inode list inconsistencies are found, the free-inode lists
are rebuilt. If FSCK is run using the SCF DIAGNOSE FILESET
command, FSCK places all free inodes in the list of inodes that
can be reused immediately.If FSCK is run automatically by the
OSS Monitor as a result of a failure of an OSS name server, FSCK
places all free inodes in the list of inodes that cannot be reused
until after an unmount and remount sequence.
There are references to an inode but the inode itself does not exist.
FSCK corrects this inconsistency as follows:
SeriousMissing inode
• If the missing inode is /, /E, /G, /lost+found, or /dev, it
is added as a directory.
• If the missing inode is /dev/tty, that special file is added.
• If the missing inode is /dev/null, that special file is added.
• If the missing inode appears as a parent in one or more PXLINK
records, it is added as a directory in the new PXINODE file.
• If there is a nonempty ZYQ file corresponding to the missing
inode and if the disk process link count for that file is nonzero,
the missing inode is added as a regular file that refers to the
ZYQ file.
• If none of the above apply, any references to the missing inode
are omitted from the new catalog.
An inode has more links than are allowed (1 for directories, 20
for other inodes). Those links in excess of the maximum are omitted
from the new PXLINK file.
SeriousToo many links
If FSCK detects a loop in the directory graph, it breaks the loop
by deleting a PXLINK record in the loop. Such a loop occurs when
SeriousLoop in directory graph
an inode is linked through other inodes back to itself; this means
that the directory referred to by the inode number is its own parent.
There is no PXINODE record with this number as the key, but the
inode number does not appear in any free-inode block. FSCK
MinorLost inode number
includes the inode in the appropriate free-inode list in the new
PXINODE file. Although this is a minor inconsistency, it is also
corrected as part of resetting the mounted flag. For more
information, see Nonzero mounted flag.
An inode has no links. The inode is given the name
#inode_number and is placed in the fileset’s /lost+found
directory.
SeriousOrphan inode
Checking and Repairing Fileset Integrity 163