Fix cannot access internet in your docker container

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I use docker for testing environment. Somehow I found out that the docker container cannot access the internet and the solution is really simple:

$ sudo ifconfig docker0 down
$ sudo service docker restart
$ sudo ifconfig docker0 up

Or

$ sudo vim /etc/default/docker
DOCKER_OPTS="--dns 10.10.4.14 --dns 8.8.8.8 --dns 8.8.4.4"

Which:
10.10.4.14 in my localhost/laptop