How to boot from a slice other than "a"?

[Wojciech Puchar]

>
> Hmm... guess I didn't realize there was a difference :)
>
> I want the OS to "run" from /dev/da0s1h so that I can then completely wipe 
> and replace /dev/da0s1a [1].



>
>> if second - add:
>> 
>> vfs.root.mountfrom="ufs:da0s1h"
>
> to which file?

loader.conf

>
> [1] The box is a new 5.3 install.  My thought was to boot from da0s1h, 
> buildworld/kernel for 6 with a DESTDIR pointing to the original / (da0s1a). 
> Then reboot and have a clean install of 6.

no need to do it that way.