Filesystem layout with sperated /boot partition

[Erik Trulsson]

On Mon, Apr 03, 2006 at 02:33:42AM +0000, valentin_nils at be-known-online.com wrote:
> Hello FreeBSD Fans,
> 
> I wanted to create a new system and was thinking about the following layout.
> 
> Size | Mountpoint | Device name | File system
> 100M /boot /dev/ad2s1a UFS2+S
> 1024MB --- /dev/ad2s1b SWAP
> 15GB / /dev/ad2s1c UFS2
> 
> I want to put /boot on its own partition, but somehow I dont have a lot of luck.
> I can install the OS, but when I reboot the bootloader will not boot.

Don't do that.  You can not have /boot as a separate partition.  It just
contains the kernel and the loader.  The other things that are needed for
booting (like /bin/sh or /sbin/mount) reside elsewhere.  (Having /boot as a
separate partition is apparently some Linux-specific convention.)

What is normally done under FreeBSD when you want a small boot partition is
to create /usr and /var as separate partitions which will let you create a
small (100M) '/' partition.  (You will probably also want either a separate
/home partition for user home directories, or let them reside under
/usr/home.  (I think the latter is the default, but I am not 100% sure.)


> 
> 
> No /boot/loader
> ...
> Default: 0:ad(0,a)/boot/kernel/kernel
> boot:
> No /boot/kernel/kernel
> ...
> 
> 1) I wouldnt mind on which partition "/boot" or "/" sits or what its named, but
> I would like to separate "/boot" on a different partition and it seems like it
> wouldnt boot when I do this. Is this just a matter of updating the bootloader ?
> Wouldnt the installer do that automatically ?

See above.  You can't do that.

> 
> 2) The part which I dont get is why is "/" always ad2s1a - even when I create
> "/boot" first ? ("/boot" will become f.e. ad2s1d) and SWAP will become ad2s1b.

You need to boot from "/" and it should be partition 'a' on the slice.  It
is probably possible to change this, but it would be much more pain and
trouble than it is worth.

> 
> So what I end up with is something like
> 
> Size | Mountpoint | Device name | File system
> 15GB / /dev/ad2s1a UFS2
> 1024MB --- /dev/ad2s1b SWAP
> 100M /boot /dev/ad2s1d UFS2+S
> 
> 
> Any replies much appreciated.

A good place to start reading is the online handbook:
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/
especially the chapter on installing FreeBSD:
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/install.html
The FAQ at http://www.freebsd.org/doc/en_US.ISO8859-1/books/faq/  might also
prove helpful.

> 
> Best regards
> 
> Nils Valentin
> http://www.be-known-online.com
> 

-- 
<Insert your favourite quote here.>
Erik Trulsson
ertr1013 at student.uu.se