When detecting disks, oneSIS assigns a number to each disk it
finds as determined by the kernel order seen in
/proc/partitions. This allows the configuration to specify
that it wants to use the first disk, for example, rather than
requiring a specific device name. oneSIS can detect any disk device
that shows up as a normal block device if the appropriate drivers are loaded.
Note: For rc.preinit to
operate on a disk, the driver must already be loaded. This means the
disk driver needs to either be compiled directly into the kernel, or
the module needs to be loaded from an initramfs.