NAME

       xfs_admin - change parameters of an XFS filesystem

SYNOPSIS

       xfs_admin [ -eflpu ] [ -c 0|1 ] [ -L label ] [ -U uuid ] device

DESCRIPTION

       xfs_admin uses the xfs_db(8) command to modify various parameters of a filesystem.

       Devices that are mounted cannot be modified.  Administrators must unmount filesystems before xfs_admin or
       xfs_db(8)  can  convert  parameters.   A number of parameters of a mounted filesystem can be examined and
       modified using the xfs_growfs(8) command.

OPTIONS

       -e     Enables unwritten extent support on a filesystem that does not  already  have  this  enabled  (for
              legacy filesystems, it can't be disabled anymore at mkfs time).

       -f     Specifies that the filesystem image to be processed is stored in a regular file at device (see the
              mkfs.xfs -d file option).

       -j     Enables version 2 log format (journal format supporting larger log buffers).

       -l     Print the current filesystem label.

       -p     Enable 32bit project identifier support (PROJID32BIT feature).

       -u     Print the current filesystem UUID (Universally Unique IDentifier).

       -c 0|1 Enable (1) or disable (0) lazy-counters in the filesystem.  This operation may take quite a bit of
              time  on  large  filesystems  as  the  entire  filesystem  needs to be scanned when this option is
              changed.

              With lazy-counters enabled, the superblock is not modified or logged on every change of the  free-
              space  and inode counters. Instead, enough information is kept in other parts of the filesystem to
              be able to maintain the counter values without needing to keep them in the superblock. This  gives
              significant improvements in performance on some configurations and metadata intensive workloads.

       -L label
              Set  the  filesystem  label to label.  XFS filesystem labels can be at most 12 characters long; if
              label is longer than 12 characters, xfs_admin will truncate it and print a warning  message.   The
              filesystem label can be cleared using the special "--" value for label.

       -U uuid
              Set    the   UUID   of   the   filesystem   to   uuid.    A   sample   UUID   looks   like   this:
              "c1b9d5a2-f162-11cf-9ece-0020afc76f16".  The uuid may also be nil, which will set  the  filesystem
              UUID  to  the  null  UUID.   The uuid may also be generate, which will generate a new UUID for the
              filesystem.

       The mount(8) manual entry describes how to mount a filesystem using its label or UUID,  rather  than  its
       block special device name.

SEE ALSO

       mkfs.xfs(8), mount(8), xfs_db(8), xfs_growfs(8), xfs_repair(8), xfs(5).

                                                                                                    xfs_admin(8)