Filesystem layout with sperated /boot partition

[Erik Trulsson]

On Mon, Apr 03, 2006 at 06:16:02AM +0000, valentin_nils at be-known-online.com wrote:
> Hi Eric,
> 
> Thanks for the reply.  I have now a better understanding whats possible with
> FreeBSD. One question (last one) which I could not find an answer to in the
> online manual is :
> 
> How would you do a Dual or multi OS boot machine f.e. with Windows on 
> the first
> disk, first slice, first partition and FreeBSD on another partition ?
> 
> Would I need a boot floppy or perhaps its not possible at all ?

It is certainly possible.  Basically you just put each OS on a separate
slice (either on the same disk, or on separate disks) and use some
boot-manager that can be used to choose boot-disk.
An article that is getting a bit old, but still should be useful that
discusses this can be found at

http://www.freebsd.org/doc/en_US.ISO8859-1/articles/multi-os/index.html

(The issues mentioned in the artice about the 1024-cylinder limit can
be mostly ignored on reasonably modern systems, and there are newer
boot-managers available than those described in the article.)

> 
> Best regards
> 
> Nils Valentin
> 
> http://www.be-known-online.com
> 
> 
> 
> Quoting Erik Trulsson <ertr1013 at student.uu.se>:
> 
> >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
> >
> 
> 
> 

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