This chapter explains how to install and use the `rescue paritition' software package. NetWinder OfficeServer and DM models shipped after October 1999 include this software package by default; older systems need to be retrofitted (or sent back for upgrade) in order to make use of the new package.
If you've received your machine after October 1999, then you should already
have the rescue package installed on your system. To be sure, there are two
things to check. As
root, run the command
/dev/hda. This will list the current partition table, which should
look something like this:
Device Boot Start End Blocks Id System /dev/hda1 1 3895 1963048+ 83 Linux native /dev/hda2 3896 4026 66024 82 Linux swap /dev/hda3 4027 7921 1963080 83 Linux native /dev/hda4 7922 7944 11592 83 Linux native
The rescue partition is
/dev/hda4, and it's just a bit over 11 Megs
in size. This is a pretty sure sign that you have the image, or at least,
you have the space for the rescue image. To verify that the data is
actually there, you need to mount the partition (temporarily):
mount /dev/hda4 /mnt cd /mnt ls
mount command fails with `You must specify the filesystem
/dev/hda4 probably is not formatted and therefore does
not contain the rescue image. Otherwise, you should see a fairly standard
directory structure listed:
bin dev lib mnt sbin usr boot etc lost+found proc tmp var
If you see these directories, then you're all set. Note that from time to
time, the rescue package will be updated, so it's a good idea to
periodically install a newer version anyways. There currently isn't a way
to find out which version of the rescue package you have installed, but in
the future, we'll include a
README file in the root directory
(shown above) that will tell you which version you are looking at.
The following steps explain how to install the rescue image onto your system
(or how to upgrade to a newer rescue image; it's the same proceedure). I'm
assuming that you do actually have a
/dev/hda4 partition of at
least 10 Megs. See below for advice if you do not have this partition.
To install or update the rescue image on
/dev/hda4, follow these
rescue.tar.gzor there may be a newer version.
rootor use the
su -command to become root.
mke2fs /dev/hda4 mount /dev/hda4 /mnt
cd /mnt tar zxvpf /root/rescue.tar.gz
You will of course need to adjust the pathname on the
to reflect the location where you downloaded the rescue image.
If you have an older system where the disk is already fully allocated to partitions 1 through 3, then it's a bit difficult to install the rescue system. I would recommend using one of the other rescue methods, which are described in the Disk-Update-HOWTO.html. Instead of installing the full disk image, though, you can repartition the drive and install the rescue package only. Then the rescue package can be used to reinstall everything else.
Another option is to try and merge two partitions together. If there is
enough space free, then you can copy e.g.
/dev/hda3 over to
/dev/hda1, and then can safely split 10MB or so off from
/dev/hda3 to be used as the rescue partition. Sadly, there is no
way to resize an ext2 partition without erasing the data on it.
(There is fips, but that only works for DOS partitions).
Supposing you want to try this, then the first thing to do would be to run
df to check how much disk space is available. It should look
roughly like so:
Filesystem 1k-blocks Used Available Use% Mounted on /dev/hda1 1477028 301819 1098880 22% / /dev/hda3 1521792 1151033 292110 80% /usr
In this case, there are about 1.15 Gig on
hda3 and only 1.09 Gig of
space remaining on
hda1, so it won't fit on
could be copied the other way (making
hda3 the root filesystem) but
in that case you'd need to carefully adjust
/etc/fstab to reflect
that fact that the root filesystem is then on
remember to delete
/etc/mtab before shutting down.
To copy the data between the partitions, you would use the following series
of commands. Note that in my case,
/dev/hda3 was mounted as
/usr (as indicated in the output from
df above). On the
older systems, it was mounted on
/home instead. If that is the
case for you, then substitute
umount /dev/hda3 mount /dev/hda3 /mnt cp -avx /mnt /usr umount /dev/hda3
Now you have to edit
/etc/fstab and comment out (with the
character) the line that begins with
/dev/hda3 (You don't have to
do this if you plan to move everything right back again, after having
re-partitioned. Just don't reboot in the meantime).
You can then safely split
/dev/hda3 into two smaller pieces, using
fdisk /dev/hda. First delete the entry for partition 3, then
create a new primary partition 3. When prompted for the size, put in 10 MB
less than you have left. You can either do the math (total cylinders
divided by the total drive size times 10 MB) or just fiddle by trial and
Then create a 4th primary partition with the remaining 10 MB of space. Save
the partition table, and format both partitions. You might also want to
copy the stuff from back over from
mke2fs /dev/hda3 mke2fs /dev/hda4 # Now copy back /usr back from /dev/hda1 if desired: mount /dev/hda3 /mnt cp -avx /usr /mnt umount /mnt rm -rf /usr/. # Careful with this !! mount /dev/hda3 /usr
Don't forget to restore the
/etc/fstab file if you changed it.
Then you can install the rescue image onto
/dev/hda4 as described