How to auto load kernel module on system boot in CentOS 5

Thursday, 24th June 2010

If you’re in need to auto load a kernel module during boot time on CentOS 5 Linux, but you want to do it in the “proper way” instead of placing it directly into the good old /etc/rc.local .
Then it might be a good idea to know that CentOS is loading it’s kernel modules using the wrapper script /etc/rc.sysinit
In that script there is a small for loop which instructs the system to load all scripts located in the /etc/sysconfig/modules/ directory.
Thereafter a quick way to include a new kernel module to auto boot up on startup could be accomplished through:

echo "modprobe somemodulename" > /etc/sysconfig/modules/somemodulename.modules
chmod +x /etc/sysconfig/modules/somemodulename.modules

Here I’ll illustrate with a real life example, let’s say you’re in need to auto lood during server boot process the kernel module softdog which is a must have in most Linux hardwares since they don’t include a hardware watchdog equipped with it.

Execute the commands below to instruct your CentOS to autoload the softdog kernel module next time on boot:
[hipo@centos-server ~]# echo -e '#!/bin/shnMODULES="softdog' > /etc/sysconfig/modules/softdog.modules
[hipo@centos-server ~]# echo -e "for i in $MODULES ; donmodprobe $i >/dev/null 2>&1; done" >> /etc/sysconfig/modules/softdog.modules
[hipo@centos-server ~]# echo "modprobe watchdog" >> /etc/sysconfig/modules/softdog.modules
[hipo@centos-server ~]# chmod +x /etc/sysconfig/modules/softdog.modules

To also load the same module immediately use modprobe

[hipo@centos-server ~]# /sbin/modprobe softdog

This kind of approach to the problem should also work in other Redhat based Linux distributions like Redhat, Fedora, RHEL etc.
A similar article to this could be seen on The really right, modern and clean way to load modules in CentOS 5

Share this on:

Download PDFDownload PDF


Leave a Reply

CommentLuv badge