A.3.2. Commands and Interfaces that Support udev
Table A.2, “dmsetup Commands to Support udev” summarizes the
dmsetup commands that support udev integration.
| Command | Description |
|---|---|
dmsetup udevcomplete | Used to notify that udev has completed processing the rules and unlocks waiting process (called from within udev rules in 95-dm-notify.rules). |
dmsetup udevcomplete_all | Used for debugging purposes to manually unlock all waiting processes. |
dmsetup udevcookies | Used for debugging purposes, to show all existing cookies (system-wide semaphores). |
dmsetup udevcreatecookie | Used to create a cookie (semaphore) manually. This is useful to run more processes under one synchronization resource. |
dmsetup udevreleasecookie | Used to wait for all udev processing related to all processes put under that one synchronization cookie. |
The
dmsetup options that support udev integration are as follows.
--udevcookie- Needs to be defined for all dmsetup processes we would like to add into a udev transaction. It is used in conjunction with
udevcreatecookieandudevreleasecookie:COOKIE=$(dmsetup udevcreatecookie) dmsetup command --udevcookie $COOKIE .... dmsetup command --udevcookie $COOKIE .... .... dmsetup command --udevcookie $COOKIE .... dmsetup udevreleasecookie --udevcookie $COOKIE
Besides using the--udevcookieoption, you can just export the variable into an environment of the process:export DM_UDEV_COOKIE=$(dmsetup udevcreatecookie) dmsetup command ... dmsetup command ... ... dmsetup command ...
--noudevrules- Disables udev rules. Nodes/symlinks will be created by
libdevmapperitself (the old way). This option is for debugging purposes, ifudevdoes not work correctly. --noudevsync- Disables
udevsynchronization. This is also for debugging purposes.
For more information on the
dmsetup and its options, see the dmsetup(8) man page.
The LVM commands support the following options that support
udev integration:
--noudevrules: as for thedmsetupcommand, disablesudevrules.--noudevsync: as for thedmsetupcommand, disablesudevsynchronization.
The
lvm.conf file includes the following options that support udev integration:
udev_rules: enables/disablesudev_rulesfor all LVM2 commands globally.udev_sync: enables/disablesudevsynchronization for all LVM commands globally.
For more information on the
lvm.conf file options, see the inline comments in the lvm.conf file.
