Troubleshooting networking in Ubuntu Server 6.06

Ubuntu stores the MAC address of eth0 in a file. Because MAC addresses change when they are used on another host, this breaks networking.

To fix:

1. Edit the iftab

   vi /etc/iftab
   

2. Find the line beginning eth0
3. Comment out the line with a #, save the file
4. Test

   ifup eth0
   ifconfig
   

This behaviour is worked around in the 6.06.1 image on this site.