single user v multiuser boot
Robert Watson
rwatson at FreeBSD.org
Fri Feb 18 20:48:30 GMT 2005
On Fri, 18 Feb 2005, Warner Losh wrote:
> One can get to single user mode without a fully working vm system. One
> can get to single user mode without having process termination working
> or image rundown working. Multiuser also requires that the various
> synchronization primitives be fully functional. So things like
> fork/exec don't have to work completely. Back when /sbin/init and
> /bin/sh were statically linked, getting to single user didn't even
> require mmap to work correctly.
I think the defintions so far have been pretty developer-centric. From a
user perspective, the benefit of single user mode is that, other than
/sbin/init, /bin/sh, and some /dev entries necessary to launch a process,
there are few dependencies to get into a maintenance mode that can be used
to partially start the system, perform recovery, etc. I frequently use
networking, swap, etc, from single-user, but with single-user you get the
choice to say "don't depend on <x>, because it's broke".
Robert N M Watson
More information about the freebsd-current
mailing list