Description of problem:
Sometimes, downloading a docker image fails. This wouldn't be that much of a problem, if it could be quickly restarted, but the timeout seems to be over a minute and Ctrl+C doesn't kill the attempt to download (runs in the background) and prevents a retry, until the last one finishes.

Version-Release number of selected component (if applicable):
Docker version 1.7.1.fc22, build b6416b7/1.7.1

How reproducible:
Sometimes

Steps to Reproduce:
1. Make sure not to have the containers for the image downloaded.
2. docker run -it fedora:latest bash

Actual results:
Unable to find image 'fedora:latest' locally
Trying to pull repository docker.io/fedora ... failed
Get https://index.docker.io/v1/repositories/library/fedora/images: dial tcp: lookup index.docker.io: No address associated with hostname

Expected results:
Successful download and run.

Additional info:
The only way to retry quickly, is to restart docker.service. After this, it usually works, so I am sure it's not a docker.io blackout.