Comment 2 for bug 1725353

The reason that the "terminal" appears to be broken to you while the browser works fine is that your DNS is not configured or misconfigured. When the browser uses a proxy it does not do dns resolution locally, the proxy server does. But your 'apt-get update' is not using the proxy.

Please give some more information on what exactly you did to:
  "configured proxy and static IP"

Did you use network-manager? Did you edit files in /etc/ ?

After supplying that information, please move this bug back to 'New' status.