update to 8.0-RELEASE --> partition gone

[Marian Hettwer]

Hej Marcel,


On Tue, 15 Dec 2009 16:46:27 -0800, Marcel Moolenaar <xcllnt at mac.com>
wrote:
> 
> Yes, if you have ad2a and not ad2s1a, then you have a
> proper dangerously dedicated disk and FreeBSD 8.x will
> work correctly with your disk.
> 
> If you installed "dangerously dedicated" and ended up
> with ad0s1a (note the "s1"), then you have an invalid
> partitioning and FreeBSD 8.x will not give you what
> you've been getting on FreeBSD 7.x. Most of the time
> you only need to wipe out the second sector on the
> disk to clean it up and have FreeBSD 8.x also give
> you ad0s1a.
>
okay... but how do I wipe out the second sector?
dd if=/dev/zero of=/dev/ad8 count=1
would wipe out the first 512 bytes. I'm always confused with sectors vs.
bytes.

hm... since this disk is my second disk and was only used for backups, I
might as well bsdlabel and newfs it again. Losing all data then, but well,
sounds easier so far to me.
And I'd like to avoid reboots, if possible.

Again, I'm booting from ad4 and this works fine. I should be able to toy
around with ad8 without rebooting or going into single user.
 
Thanks so far,
Marian