Difference in slice numbering FreeBSD 4.x vs. 6.x?

[Giovanni P. Tirloni]

Torfinn Ingolfsen wrote:
> Hi,
> 
> Yes, this is a strange question; is the slice numbering in FreeBSD 4.x
> different from that in FreeBSD 6.x?
> I'm talking about for fdisk(8), boot(8) and loader(8).
> Background: I have this old laptop (a HP OmniBook 5500CT). I replaced
> the tiny (1.2GB) hard drive in it with a 20GB hard drive.
> I installed FreeBSD 4.11-RELEASE on it, using fdisk to partition the
> disk in two. 4.11-R installed on slice1, ie. root on /dev/ad0s1a.
> All was well.
> 
> Now, the story:
> Then I decided to install FreeBSD 6.0-RELEASE on the second half of the
> disk, but it didn't work out of the box. To make a long story short, it
> turned out that the PCCard controller / slots wasn't detected properly,
> and as this laptop doesn't have a cd-rom drive, I just took out the hard
> drive, mounted a 2.5-to-3.5 inchadapter on it and put it into another
> machine. This machine had a cd-rom, and it installed FreeBSD 6.0-R on
> the second slice without a problem.
> I even testedt that it would boot both slices (4.11-R or 6.0-R) on that
> machine, it did. On this machine, 4.11-R was on slice 1, and 6.0-R on
> slice 2.
> 
> Now, I took the hard drive out and put it into the laptop again.
> Mahor problem - it wouldn't boot at all. A not-so-quick boot with the
> floppies (3 floppies for boot, plus the fixit floppy) later, I ran fdisk
> on ad0.
> Much to my surprise, the twor FreeBSD installations had now moved to
> slice 3 and slice 4.
> 4.11-RELEASE on slice 3 and 6.0-RELEASE on slice 4.
> 
> I am utterly amazed by this. What has happened?

  I've moved hard disks around many times and this has never happened. 
Can you send us `fdisk /dev/ad0` from 4.11 and 6.0 so we can spot 
anything not normal ? Does it still boot in the machine after we've 
booted in the laptop ?

-- 
Giovanni P. Tirloni
http://blog.tirloni.org