diff options
Diffstat (limited to 'lib/geom/label/glabel.8')
| -rw-r--r-- | lib/geom/label/glabel.8 | 55 |
1 files changed, 44 insertions, 11 deletions
diff --git a/lib/geom/label/glabel.8 b/lib/geom/label/glabel.8 index 5283a604e45b..da958b52befd 100644 --- a/lib/geom/label/glabel.8 +++ b/lib/geom/label/glabel.8 @@ -22,7 +22,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd March 12, 2017 +.Dd April 19, 2024 .Dt GLABEL 8 .Os .Sh NAME @@ -113,11 +113,11 @@ CD ISO9660 (directory EXT2FS (directory .Pa /dev/ext2fs/ ) . .It -REISERFS (directory -.Pa /dev/reiserfs/ ) . -.It NTFS (directory .Pa /dev/ntfs/ ) . +.It +Swap Linux (directory +.Pa /dev/swaplinux/ ) . .El .Pp Support for partition metadata is implemented for: @@ -137,14 +137,35 @@ e.g. .Pa /dev/diskid/DISK-6QG3Z026 . .Pp Generic labels created and managed solely by -.Xr glabel 8 +.Nm are created in the .Pa /dev/label/ directory. +Note that generic, automatic labels occupy some space on the device +and thus should not be added to a device already containing a file system. +In particular, +.Nm +reserves the last sector of the device to store the label information. +If the device already contains a file system, +.Nm +will overwrite the last sector, possibly damaging the file system, and the +file system may later overwrite the label sector. +Instead, create a label before initializing the file system, and initialize +that file system on the device created by +.Nm +under the +.Pa /dev/label/ +directory. +Then the file system will correctly account for the space occupied by the +generic label, +since the +.Nm +device will be one sector smaller than the device from which it was created. .Pp Note that for all label types, nested GEOM classes will cause additional device nodes to be created, with context-specific data appended to their -names. E.g. for every node like +names. +E.g. for every node like .Pa /dev/label/bigdisk there will be additional entries for any partitions which the device contains, like @@ -152,6 +173,17 @@ contains, like and .Pa /dev/label/bigdiskp1a . .Pp +.Nm +requires write access to a device to create, modify, and destroy +"automatic" labels. +It will fail to persist changes if they are applied while a file +system on the device is currently mounted. +To ensure that modifications are stored across a reboot, the file system +needs to be unmounted first. +If the device holds the system's root file system, entering into +single user mode and mounting in read-only mode is required to persist +the change. +.Pp The first argument to .Nm indicates an action to be performed: @@ -232,12 +264,13 @@ Most .Nm LABEL providers implement a .Xr sysctl 8 -flag and a tunable variable named in the above format. This flag -controls if the label provider will be active, tasting devices +flag and a tunable variable named in the above format. +This flag controls if the label provider will be active, tasting devices and creating label nodes in the -.Xr devfs 5 -tree. It is sometimes desirable to disable certain label types if -they conflict with other classes in complex GEOM topologies. +.Xr devfs 4 +tree. +It is sometimes desirable to disable certain label types if they +conflict with other classes in complex GEOM topologies. .El .Sh EXIT STATUS Exit status is 0 on success, and 1 if the command fails. |