Can RAID driver be loaded from loader.conf?

Dan Nelson dnelson at
Wed Feb 9 23:04:37 UTC 2011

In the last episode (Feb 10), Toomas Aas said:
> I'm preparing for a migration from single SATA disk attached to onboard
> SATA controller to 3ware 9750-4i RAID system.  In preparation, while the
> system is still running on single disk, I downloaded the latest tws.ko
> driver from LSI website and added it to loader.conf: tws_load="YES"
> Further plan is to install the controller and new disks into the system
> alongside with the existing disk, create partitions on new disk and copy
> over all the contents using dump and tar.  After that remove the existing
> single disk.
> Is it safe to assume that the system will boot from RAID if RAID
> controller driver is loaded from loader.conf, or is it absolutely required
> to have the RAID driver statically built into the kernel?

You should be able to load raid drivers as modules just fine.  /boot/loader
uses BIOS calls to read both the kernel and any modules listed in
loader.conf, so if it can load the kernel, it should be able to load the
modules too.

	Dan Nelson
	dnelson at

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