Remember to load your kernel modules at boot
During my holiday I had a server rebooted due to a scheduled mainteinance of my service provider.
This server was a steady one, this was the first reboot after over an year.
After the reboot, suddently some scripts stopped working. A kernel module was not loaded at boot time, causing a partial block of network connectivity.
Probably, when I setup the server over a year ago, I loaded the module manually using modprobe and I forgot to set it up at boot time.
So if you are using CentOS 6.x branch and you have to load a kernel at boot please remember to create an executable script called <your_module>.modules into /etc/sysconfig/modules directory.
Then your file should contains this line of code:
#!/bin/shexec /sbin/modprobe <your_module> 2>&1
This way CentOS will load your kernel modules at boot.
More on this on Red Hat documentation online.
