[syslinux] syslinux raid mode

[H. Peter Anvin]

Tomas M wrote:
> I noticed syslinux-3.50 implements some 'raid mode' (-r option), which 
> should be used to boot the next device.
> 
> But there is nothing about it in the documentation.
> Would you please describe what does it do?
> 
> I assume it's something different than chainloading a boot loader from 
> different disk/partition, right?
> 

RAID mode changes the behaviour in the case of a disk failure.

Normally, on disk failure, syslinux prints an error message and stops.
In RAID mode, it returns to the BIOS with INT 18h, which with a properly
functioning BIOS will cause it to boot the next device in sequence.  If
syslinux is used on a RAID-1 /boot, then this will attempt to boot the
next drive in the mirror set.

	-hpa