i compiled a new kernel recently and for some reason i installed the iso filesystem support module(for reading cdroms) as a module. i figured the "Automatic kernel module loading" that i had enabled would take care of it, but when i put the cdrom in and tried to mount it, i couldnt. i had to modprobe the driver before i could mount a cdrom. what i dont understand is my usb thumb drive, for example relies on a bunch of scsi and usb-mass-storage drives and they get loaded up as soon as i stick it in.

OK, I'll bite on this one. There are two ways to do this. You can do a module or compile it into the kernel itself. Personally, I hate modules, I compile everything in that I can. My sensors and nvidia drivers are all I have as modules.

Here is the screen:


Note the "M" in there, that means it will make it as a module and you either have to load it manually or tell it to load it when booting.

Another example:

The "*" means it will be compiled into the kernel, NOT a module. It also means that if you want to change it, you will have to recompile a new kernel and reboot.

Now to the problem you are having. If you want the module to load automatically when you boot, just add it to the file in /etc/modules.autoload.d/kernel-2.6. That assumes you are using a 2.6 kernel. If you are using a 2.4 then add it to kernel-2.4 file instead. It should load the module during the boot process the next time.

That help any?

When your usb is getting plugged in a service called hotplug is getting invoked. This is different than the autoloading of kernel modules although conceptually they seem related.