A problem I've been having recently with a couple of Ubuntu 14.04 servers is receiving a "Waiting for network configuration" and "Waiting up to 60 seconds more for network" messages on boot, despite all network functions being available once it's finished booting. I've so far tracked it down to an issue with the servers that have both static IP addresses set and Samba installed through Aptitude.

The fix I found for it is updating your /etc/network/interfaces file so that the static IP address assignment looks something like the following:

	# The primary network interface
	allow-hotplug eth0
	iface eth0 inet static
	        address 192.168.0.40
	        netmask 255.255.255.0
	        network 192.168.0.0
	        gateway 192.168.0.1

The important part here that solved the issue for me is `allow-hotplug eth0` (or em0 or whatever your primary interface identifier is) instead of the commonly used `auto eth0`. This fixed the issue for me and subsequent boots performed admirably.