devswmgr(8)devswmgr(8)NAMEdevswmgr - utility to manage the device switch database
/sbin/devswmgr [-option [parameter]]
Displays the following information about the device switch database:
Whether a device switch database was read from the primary file
or from a backup file
The number of entries that are in the device switch table Dis‐
plays the major numbers that have been reserved by all drivers,
a named driver, or an instance of a named driver.
A driver that requires more than one entry in the device switch
table uses a unique instance number to reference each of its
device switch table entries. Displays help for the devswmgr
command. Releases all the major numbers for a device driver if
just the driver name is specified. Releases one major number
for a device driver if the NAME and the INSTANCENUM of the
driver are specified.
The devswmgr command helps you manage the device switch table by dis‐
playing information about the devices drivers in the table.
You can also use the command to release device switch table entries.
Typically, you release the entries for a driver after you have unloaded
the driver and do not plan to reload it later. Releasing the entries
frees them for use by other device drivers.
The following example shows that a device switch table was loaded from
the primary device and that there are 70 entries in it: %
/sbin/devswmgr -display Device switch information
device switch database read from primary file
device switch table has 70 entries The following example shows the
major numbers in the device switch table that have been reserved for
the driver named cam_disk: % /sbin/devswmgr -getnum driver=cam_disk
Device switch reservation list
(*=entry in use)
driver name instance major
cam_disk 1 8*
The file that manages the device switch databases The primary device
switch database file The backup device switch database file