Persistent Module Loading - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

Persistent Module Loading

To print to the screen all commands as /sbin/modprobe executes them, use the -v option. For
example:
/sbin/modprobe -v e100
Output similar to the following is displayed:
/sbin/insmod /lib/modules/2.6.9-5.EL/kernel/drivers/net/e100.ko
Using /lib/modules/2.6.9-5.EL/kernel/drivers/net/e100.ko
Symbol version prefix 'smp_'
The /sbin/insmod command also exists to load kernel modules; however, it does not resolve
dependencies. Thus, it is recommended that the /sbin/modprobe command be used.
To unload kernel modules, use the /sbin/rmmod command followed by the module name. The
rmmod utility only unloads modules that are not in use and that are not a dependency of other modules
in use.
For example, the command
/sbin/rmmod e100
unloads the e100 kernel module.
Another useful kernel module utility is modinfo. Use the command /sbin/modinfo to display
information about a kernel module. The general syntax is:
/sbin/modinfo [options]<module>
Options include -d, which displays a brief description of the module, and -p, which lists the
parameters the module supports. For a complete list of options, refer to the modinfo man page (man
modinfo).
41.2. Persistent Module Loading
Kernel modules are usually loaded directly by the facility that requires them, which is given correct
settings in the /etc/modprobe.conf file. However, it is sometimes necessary to explicitly force the
loading of a module at boot time.
Red Hat Enterprise Linux checks for the existence of the /etc/rc.modules file at boot time, which
contains various commands to load modules. The rc.modules should be used, and notrc.local
because rc.modules is executed earlier in the boot process.
For example, the following commands configure loading of the foo module at boot time (as root):
# echo modprobe foo >> /etc/rc.modules
# chmod +x /etc/rc.modules
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