Loading and Unloading Modules in Linux

In this article I will give an example of manual and automatic loading/unloading models in Linux.

First, switch to root user if not under it, for example in Ubuntu it can be done like this:

sudo -i

Let’s see a list of the downloaded modules:

lsmod

To see if a particular module has been loaded so it can (where NAME is the module name):

lsmod | grep NAME

The following commands are used to load/unload a module:

modprobe NAME
modprobe -r NAME

When the module load command is executed, modprobe looks for it in the directory:

/lib/modules/$(uname -r)

You can see what it is like:

ls /lib/modules/$(uname -r)
ls /lib/modules/$(uname -r)/kernel/net/netfilter/

To load/unload a module from another directory, you can execute the following commands:

insmod /path/to/module/name.ko
rmmod /path/to/module/name.ko

View information about the module and the possible startup parameters as follows:

modinfo NAME

You can see specific information about the module, for example, where it is located:

modinfo --filename NAME

In order for the modules to start at the very beginning of the system startup, they must be written to the /etc/modules.conf file, and in order to start last when all services are started, the file is /etc/rc.local.
In addition to the file /etc/modules.conf there is also a directory /etc/modprobe.d/, where there are similar files with the extension .conf.

For example, in rc.local modules are written like this:

/sbin/modprobe NAME

The modules.conf file is written like this:

nf_nat_ftp

To prevent the module from loading, you can write the word blacklist before the module name:

blacklist NAME

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