The glabel utility is used for GEOM provider labelization. A label can be set up on a GEOM provider in two ways: "manual" or "automatic". When using the "manual" method, no metadata are stored on the devices, so a label has to be configured by hand every time it is needed. The "automatic" method uses on-disk metadata to store the label and detect it automatically in the future.
This 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 (directory /dev/ufs/).
- UFS2 (directory /dev/ufs/).
- MSDOSFS (FAT12, FAT16, FAT32) (directory /dev/msdosfs/).
- CD ISO9660 (directory /dev/iso9660/).
- EXT2FS (directory /dev/ext2fs/).
- REISERFS (directory /dev/reiserfs/).
Non file-system labels are created in the directory /dev/label/.
The first argument to glabel indicates an action to be performed: