can't make an 'a' slice except with auto-defaults

[Steve Franks]

> Why so complicated? The command
>
>        # newfs /dev/ad1

I'm looking to mirror/dup/image the entire system to something I can
stick in another system.    I hear there's good reasons for not
running my whole system off of a single partition.  The 'other' system
has 7.2 and has devolved to a 25% chance of a hard freeze every time I
unplug a ucom device (seems to have cropped up between 7.2-release and
7.2-stable#3).  8 likes usb, so I like 8.

Steve