Making world but no kernel

[Michal Varga]

On Tue, 2011-07-26 at 13:04 +0200, Jerome Herman wrote:
> Hello,
> 
> I would like to know if it is possible to rebuild world, but without 
> upgrading or even compiling the kernel.
> 
> The problem is such : I am presently working on a FreeBSD station that 
> seems to have quite a lot of problem, notably with fsck. I am starting 
> to wonder whether this BSD station was properly installed, or if some of 
> the system tools were pasted from older FreeBSD setup.
> Since the machine is in a remote location, I would prefer to avoid full 
> reinstall if possible. Among other things, single user mode is not 
> available.
> 
> So I was wondering, if I get the full sources with sysinstall, can I 
> make buildworld and then installworld without going through the kernel 
> phase or would this be a bad idea ?
> 
> Thanks for your help
> 
> Jerome Herman

`make buildworld installworld` won't build and install new kernel at
all, so that basically answers your first question. You'd need to use
`make buildworld installworld kernel` for that effect.

To answer your other concern - reinstalling FreeBSD "on the fly" should
be without any issues as long as you use the right src revisions
corresponding to your current system (and kernel). Mixing worlds and
kernels of different revisions should *mostly* work if there were no ABI
changes during that time period, but you probably don't want trying this
blindly without any means of recovery. Basically - it's doable, but I
wouldn't do it with just a single shot on my disposal.

Note that you don't necessarily need to install a new kernel in single
user mode. While this is generally a good practice and a "safer way to
do things", I haven't even done this for half a decade, and I'm
re/installing FreeBSD builds practically on a daily basis.

My advice:
Personally, I'd consider it much safer to roll a new build of kernel
along with the world, but again, that's just me. As you're already fully
rebuilding a possibly broken installation (which you didn't do and thus
don't know everything that might be rotting inside), chances of some
magical failure are already pretty decent. Rolling an up-to-date kernel
with the rest of the world shouldn't make them any lower, on the
opposite, might even raise your chances of a successfull reboot.

m.

PS: Whatever that means, please don't get your sources through
"sysinstall", that monster shouldn't even be present in a seriously
maintained FreeBSD installation. Get your sources "the proper way" with
csup:

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/cvsup.html

(note - "csup", not "cvsup", it's explained on the page in detail)


-- 
Michal Varga,
Stonehenge (Gmail account)