sudo mkdir /rescue
sudo mount -t tmpfs tmpfs /rescue
sudo debootstrap sarge /rescue http://apt-proxy.kurp.hut.fi:9999/debian
sudo mount -t proc proc /rescue/proc
sudo mount -t devpts devpts /rescue/dev/pts
sudo cp /etc/resolv.conf /rescue/etc/resolv.conf
sudo cp /etc/hosts /rescue/etc/hosts
sudo apt-get --download-only --reinstall install ssh
sudo apt-get --download-only --reinstall install lsof
sudo cp /var/cache/apt/archives/ssh_1%3a3.8.1p1-8.sarge.4_i386.deb /rescue/tmp
sudo cp /var/cache/apt/archives/lsof_4.74.dfsg.3-2_i386.deb /rescue/tmp
sudo chroot /rescue dpkg -i /tmp/ssh_1%3a3.8.1p1-8.sarge.4_i386.deb
sudo chroot /rescue dpkg -i /tmp/lsof_4.74.dfsg.3-2_i386.deb
sudo emacs -nw /rescue/etc/ssh/sshd_config # Port 10022
sudo chroot /rescue /etc/init.d/ssh start
sudo chroot /rescue passwd

sudo cp -a /sbin/init /sbin/init.backup
sudo dd of=/sbin/init.chroot <<EOF 2>/dev/null
#!/bin/sh
cd /rescue
mkdir old-root
pivot_root . old-root
exec chroot . sh -c "exec /sbin/init" \
        <dev/console >dev/console 2>&1
EOF
sudo chmod a+x /sbin/init.chroot
sudo rm /sbin/init
sudo cp -a /sbin/init.chroot /sbin/init
sudo /sbin/init.backup u

# ssh as root to port 10022
cp -a /old-root/sbin/init.backup /old-root/sbin/init
# kill all processes that use /old-root
umount -l /old-root/dev
umount /old-root

fsck -f /dev/hda1

# return to old system
mount /dev/hda1 /old-root
mount -t proc proc /old-root/proc
mount -t devpts devpts /old-root/dev/pts
chroot /old-root /etc/init.d/ssh start

cp -a /sbin/init /sbin/init.backup
cat > /sbin/init.chroot <<EOF
#!/bin/sh
cd /old-root
mkdir old-root
pivot_root . old-root
exec chroot . sh -c "exec /sbin/init" \
        <dev/console >dev/console 2>&1
EOF
chmod a+x /sbin/init.chroot
rm /sbin/init
cp -a /sbin/init.chroot /sbin/init
/sbin/init.backup u

# ssh as root to port 22
cp -a /old-root/sbin/init.backup /old-root/sbin/init
umount /old-root/proc
umount /old-root/dev/pts
umount /old-root