hi, thanks for the help!
Mounting /dev/ad5e worked (at least in read-only, it wants a fsck) so
rather than try a repair, and risk blowing it up, (and I'm on 4.8, which
still has disklabel nor bsdlabel) I'll copy everything off and
re-initialise the disc in due course.
Thanks!
Rob.
At 15:53
It looks like you wrote the disklabel for the slice to the disk or
vice-versa.
If you check /dev there probably isn't a /dev/ad5s* there. Try mounting
/dev/ad5e instead of /dev/ad5s1e. To verify, do a bsdlabel ad5s1 to see if
you have a disklabel for the slice. Otherwise you could :
1.backup