On a fresh Ubuntu 12.04 installation, we noticed that we were having issues with openssh as it was constantly breaking the connection randomly after a period of time. After doing some debugging, we found that we were able to consistently replicate the issue as follows:
ping google.com #works sudo apt-get clean #no issues sudo apt-get update #stays at 0%, must ^C to exit ping google.com #no longer connects
The only method that can be used to restore DNS access is to reboot the machine.
Additional info: We have replaced the resolve.conf symlink with an actual file to specify google's nameserver 18.104.22.168 (which I have personally done before in 12.04 in our network without issues). The machine is in a static network without DHCP and is issued a static IP address. There are no issues pinging the machine from elsewhere in the network, but when openssh was installed the ssh connection would be refused.
Anyone have any suggestions on how to resolve this?