Notes to self.
The error message "Operation failed!" from pump or dhclient can mean that the Linux module af_packet.o isn't loaded (also often associated with the SIOCGIFADDR error). This is really annoying and not very useful. Hopefully by writing this down I will never forget this two day lesson again. -- AdamShand
udhcpc is a really cool little dhcp client (udhcpd is a pretty cool little server). -- AdamShand