fix_clone_networking.sh

# fix_networking.sh
#
# This script automates the steps outlined at:
# 
# http://weblog.jamisbuck.org/2008/8/15/cloning-ubuntu-hardy-image-in-vmware-fusion
#
# for fixing the networking on a copied Ubuntu VMWare image.

usage() {
cat <<EOF
$0 [new hostname]

  Changes the hostname on the guest OS and fixes the udev rule screwed up by
  VMWare assigning a new MAC address to the copied image.
EOF
}


if [ -n "$1" ]; then
  NEW_NAME=$1
  OLD_NAME=`hostname | sed 's/\([\.]*\)\..*/\1/'`
  if [ $NEW_NAME = $OLD_NAME ]; then
    echo "Warning: new name identical to current hostname."
  fi
else
  usage
  exit
fi

echo "Change current hostname."
sudo hostname $NEW_NAME

echo "Changing hostname in /etc/hostname and /etc/hosts"
sudo sed -i -e"s/$OLD_NAME/$NEW_NAME/" /etc/hostname
sudo sed -i -e"s/$OLD_NAME/$NEW_NAME/g" /etc/hosts

echo "Fixing udev rule for eth0."
UDEV_RULES=70-persistent-net.rules
# Ubuntu will just add a new rule when it detects the new MAC address.
# I'm just making a backup of the original udev file and replacing it with
# the last rule, making the substitution eth1 -> eth0.
sudo mv /etc/udev/rules.d/$UDEV_RULES /tmp/$UDEV_RULES
sudo sh -c "grep '^SUBSYSTEM' /tmp/$UDEV_RULES | tail -n 1 | sed 's/eth1/eth0/' > /etc/udev/rules.d/$UDEV_RULES"

echo "Please restart ('sudo reboot')"