Help with boot0

Henrik W Lund henrik.w.lund at
Sat Nov 13 14:17:51 GMT 2004

Jay O'Brien wrote:
> I have two identical hard drives on the same IDE controller;
> The file systems are identical. I can move the "Master" jumper 
> from one HD to the other and the computer will boot on the 
> HD with the jumper. It becomes ad0 and the other HD is ad1. 
> I have installed boot0cfg on both drives with the -B option. 
> Booting with either drive gives me a F1 (FreeBSD) option and a 
> F5 (Disk1) option. F1 boots the drive set up with the hardware 
> jumper to be the IDE controller master. F5 gives another 
> selection, F1 (FreeBSD) and F5 (Disk2). F1 boots on the IDE 
> master, and F5 won't boot.
> I would like to be able to boot from either drive using the 
> bootup selection. I know both drives work fine as the boot 
> drive when selected by the hardware drive jumper. 
> What am I missing, why doesn't boot0 work for me?
> Jay O'Brien
> PS.. I'm using 4.10, and this exercise is so I can build 5.3 
> on one of the Hard drives and be able to boot to either version.

I've fiddled with the same thing in the past. You really only need boot0 
on /one/ of the drives. If you put boot0 on both, you'll eventually 
loose track of which disk's boot0 you're seeing, as F5 will switch 
between them. F1 *will* booth the disk you're currently on, but how do 
you know which disk you're on, after a few reboots? If the two drives 
are identical as well, that certainly does little to help discern the 
two drives (installing 5.3 on one of them, as you intend to do, will 
remedy this particular point, however).

Apologies if this seems belittling, but I will attempt to sketch out 
what I think is happening, based on what you write.

Boot up, this is what you see:

F1 FreeBSD  <-- This will boot your master drive with FreeBSD on it
F5 Drive 1  <-- This will attempt to boot your slave drive, which will 
result in you seeing this:

F1 FreeBSD  <-- This will boot your slave drive with FreeBSD on it (you 
write that it boots your master drive, but how do you know this for sure?)
F5 Drive 2  <-- This will attempt to boot your master drive, which will 
result in you seeing this:

F1 FreeBSD
F5 Drive 1

... while(!(cows come home))

If this is not what's happening, please explain what happens when you 
press F5 in the second boot0 menu above.

What I'd do, is remove boot0 from the slave drive and never make it 
master. If you ever need to put the slave drive in a dual-boot situation 
with it as master, installing boot0 again done in no more than 20 

Henrik W Lund

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