NAME

SYNOPSIS

DESCRIPTION

This GEOM class also provides volume label detection for file systems. Those labels cannot be set with glabel, but must be set with the appropriate file system utility, e.g. for UFS the file system label is set with tunefs(8). Currently supported file systems are:

• UFS1 volume names (directory /dev/ufs/).
• UFS2 volume names (directory /dev/ufs/).
• UFS1 file system IDs (directory /dev/ufsid/).
• UFS2 file system IDs (directory /dev/ufsid/).
• MSDOSFS (FAT12, FAT16, FAT32) (directory /dev/msdosfs/).
• CD ISO9660 (directory /dev/iso9660/).
• EXT2FS (directory /dev/ext2fs/).
• REISERFS (directory /dev/reiserfs/).
• NTFS (directory /dev/ntfs/).

Support for partition metadata is implemented for:

• GPT labels (directory /dev/gpt/).
• GPT UUIDs (directory /dev/gptid/).

Generic disk ID strings are exported as labels in the format /dev/diskid/GEOM_CLASS-ident e.g. /dev/diskid/DISK-6QG3Z026.

Generic labels created and managed solely by glabel(8) are created in the /dev/label/ directory.

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 /dev/label/bigdisk there will be additional entries for any partitions which the device contains, like /dev/label/bigdiskp1 and /dev/label/bigdiskp1a.

The first argument to glabel indicates an action to be performed:

create

Create temporary label name for the given provider. This is the “manual” method. The kernel module geom_label.ko will be loaded if it is not loaded already.

label

Set up a label name for the given provider. This is the “automatic” method, where metadata is stored in a provider's last sector. The kernel module geom_label.ko will be loaded if it is not loaded already.

stop

Turn off the given label by its name. This command does not touch on-disk metadata!

destroy

Same as stop.

clear

Clear metadata on the given devices.

dump

Dump metadata stored on the given devices.

refresh

Refresh / rediscover metadata from the given devices.

list

See geom(8).

status

See geom(8).

load

See geom(8).

unload

See geom(8).

Additional options:

-f

Force the removal of the specified labels.

-v

Be more verbose.

SYSCTL VARIABLES

kern.geom.label.debug: 0

Debug level of the LABEL GEOM class. This can be set to a number between 0 and 2 inclusive. If set to 0 minimal debug information is printed, and if set to 2 the maximum amount of debug information is printed.

kern.geom.label.*.enable: 1

Most LABEL providers implement a sysctl(8) 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 devfs(5) tree. It is sometimes desirable to disable certain label types if they conflict with other classes in complex GEOM topologies.

EXIT STATUS

EXAMPLES

glabel label -v usr /dev/da2
newfs /dev/label/usr
mount /dev/label/usr /usr
[...]
umount /usr
glabel stop usr
glabel unload

The next example shows how to set up a label for a UFS file system:

tunefs -L data /dev/da4s1a
mount /dev/ufs/data /mnt/data

SEE ALSO

HISTORY

AUTHORS