The FreeBSD Diary

You may wish to first read about a couple of other methods as supplied by other readers.

1. backup the boot drive
2. install FreeBSD on a new boot drive
3. restore the old boot drive over the new boot drive.

This procedure assumes you have enough disk space for the backup.  I'm sure there must be an easier way to do this.  If you know, please let us know your comments.   This article also assumes you know how to add a new drive to a box, set up the primary/secondary stuff (if using IDE) or set device IDs (if using SCSI).  The main thing this article shows you is how I backed up and restored the boot drive.

mkdir /mnt
mount /dev/da1s1e /mnt

The first step was to backup each file system on the boot drive.  This is slightly more complex that I first thought.  If you look at the existing mount points, you'll see what I mean:

# mount
/dev/da0s1a on / (local, writes: sync 14 async 215)
/dev/da0s1f on /usr (local, writes: sync 3 async 95)
/dev/da0s1e on /var (local, writes: sync 91 async 237)
procfs on /proc (local)

In this example, you'll see three mount points we must deal with: /, /usr, and /var.  Each mount point represents a different file system.  I decided to backup each separately.  I'm not sure why.  But I did.  I used the tar command for this.

tar cvlf /mnt/root.tar /
tar cvlf /mnt/var.tar /var
tar cvlf /mnt/usr.tar /usr

Here is a brief explanation of each option:

• p - same permissions - essential to a successful backup (not used above, but used below)
• c - creates a new archive
• v - lists the files as they go into the tarball
• l - don't cross mount points (backs up only one file system)
• f - specifies that the next argument is the output tarball

Then I did a "shutdown -h now" and powered off the box once the shutdown was complete (see the console messages for this).

Then I did a "shutdown -h now" and powered off the box once the shutdown was complete (see the console messages for this).

I mounted the spare drive:

mount /dev/da1s1e /mnt

I mounted the new boot drive.  You'll remember that we had three file system to backup.  So that requires three mount points.

mkdir /newboot
mount /dev/da2s1a /newboot
mount /dev/da2s1f /newboot/usr
mount /dev/da2s1e /newboot/var

Then I started restoring from /mnt to drive to the new boot drive:

tar xvpf /mnt/root.tar -C /newboot
tar xvpf /mnt/usr.tar -C /newboot
tar xvpf /mnt/var.tar -C /newboot

The -C option tells tar to change to the /newboot directory before untar'ing any files.

Then I did a "shutdown -h now" and powered off the box once the shutdown was complete (see the console messages for this).

1. create a small freebsd partition on the target drive.  I have 2MB on my first ide drive.
2. disklabel it, using the -B option to add some boot blocks (boot0 and boot1)
3. newfs it
4. mount it e.g. /mnt
5. then use pax/tar/cpio to copy /boot to /mnt/boot
6. edit /mnt/boot/loader.conf.local to have
   currdev=disk<n>s1a root_disk_unit=<m>
   where <n> is the BIOS disk number, and <m> is the scsi id number if you are booting from a scsi disk.
7. reboot!

This is the scheme Duncan uses to have FreeBSD booted from his scsi drives in a mixed ide/scsi setup.

1. Shutdown system and add the drive that you want to be your new boot disk
2. Partition the New Boot Drive the way you want and mount it on /mnt. ie: /mnt, /mnt/usr, /mnt/var, etc.
3. Now, you simply copy the filesystems with tar. The command to do this is:
   tar clf - -C /    . | tar xpvf - -C /mnt
   tar clf - -C /usr . | tar xpvf - -C /mnt/usr
   etc
   using a dash as the filename causes tar to read/write from/to stdin/stdout. Not quite sure why you need the dot
   at the end of the first tar command, but that's what they say in the man page.  I use it without the -p option and it
   seems to work fine, but again, the man page suggests you use it.
4. Power off the machine, swap the scsi id's and boot up.

No re-install required. You also don't have to make sure you have enough space lying around to hold the tarball.

Hope that helps,
Dean