After I changed my laptop to a static IP configuration to support mongo clustering on my local network, I was having problems with my network manager indicator in the Unity task bar showing my wired network as the device no longer being managed. Additionally, and exacerbating the issue, I could no longer connect to my work VPN using the network manager. I tried several things to resolve the issue: I restored my /etc/network/interfaces to the default (DHCP) configuration, I removed and re-installed the network manager wireless-1 configuration. Bounced eth0 repeatedly, rebooted many times, but nothing worked and I was unable to restore the device to a managed state, nor could I connect via the VPN to work.
I hit the ubuntu forums and found the solution -- edit the /etc/Network Manager/NetworkManager.conf file and change:
I rebooted and not only got the wired device managed again, but also got my VPN restored in the process. Magically.
Back to programming...