fsck_cs

FSCK_CS(8)                   System Manager's Manual                  FSCK_CS(8)

NAME
     fsck_cs – verify and repair CoreStorage logical volume groups

SYNOPSIS
     fsck_cs -q device ...
     fsck_cs -p device ...
     fsck_cs [-y | -n] [-x | -g] [-l logfile] device ...

DESCRIPTION
     The fsck_cs utility verifies and repairs CoreStorage logical volume group
     metadata.

     The device parameter(s) should be path(s) to the "raw" (character special)
     disk device(s) such as /dev/rdisk1s1 that constitute the CoreStorage
     logical volume group.  If you specify a "non-raw" (block special) path such
     as /dev/disk1s1, or just the disk name such as disk1s1, it will
     automatically be converted to the corresponding raw disk device
     (/dev/rdisk1s1).

     The options are as follows:

           -q      Performs a "quick" check and indicates if any corruptions
                   were found via the exit status.  In this mode stale MLV
                   segments are not checked, nor is proactive MLV mirror
                   scrubbing performed.

           -p      Operates in "preen" mode.  MLV mirror blocks are repaired
                   where necessary.  Newer transactions may be invalidated to
                   force a roll-back to an older, but consistent, filesystem
                   state.

           -y      Causes fsck_cs to assume "yes" as the answer to all
                   questions.  In other words, always attempt to repair any
                   errors that are found.

           -n      Causes fsck_cs to assume "no" as the answer to all questions.
                   In other words, never attempt to repair any errors that are
                   found.

           -x      Causes fsck_cs to produce its output in an XML-like (plist)
                   format.  This option is used when another application with a
                   graphical user interface (like OS X Disk Utility) is invoking
                   the fsck_cs tool and processing the output.

           -g      Causes fsck_cs to produce its output in GUI-compatible form.
                   This is similar in usage to the -x option.

           -l logfile
                   Reproduce all console output, as well as additional status
                   and error messages, to the specified file.

     Alternatively device can be specified as the UUID of the CoreStorage
     logical volume group or as the name of a CoreStorage-hosted logical volume
     within that group, causing fsck_cs to derive the constituent raw device(s)
     from the IORegistry.  In these cases you must indicate what object is being
     supplied to identify the logical volume group:

           --pv    the component CoreStorage physical volume(s) directly

           --uuid  the CoreStorage logical volume group (as a UUID)

           --lv    a CoreStorage logical volume (as a device name)

DIAGNOSTICS
     The fsck_cs utility exits with 0 if no corruption was detected or if all
     corruptions were repaired, and with >0 if any unrepaired corruption
     remains.

BUGS
     fsck_cs does not perform an exhaustive validation, nor is it able to fix
     many of the inconsistencies that it does detect.

HISTORY
     The fsck_cs utility first appeared along with CoreStorage in OS X 10.7.0.

OS X                              July 22, 2011                             OS X