Cannot connect to internet from inside a docker container in Ubuntu VM

Question

Hi,

I am trying to access internet from inside docker containers in an Ubuntu VM. According to the azure documentation found here: https://learn.microsoft.com/en-us/azure/virtual-network/deploy-container-networking#deploy-plug-in-for-docker-containers

I deployed the plugin, also created the container using the command ./docker-run.sh ... but still there is no internet access from inside the container, I am not able to run any commands in the container like ping, curl, apt-get, etc so Internet is not yet enabled in the docker container.

Is there a way that I can troubleshoot or test that conectivity to internet from inside the docker container?

Answer 1

Hello Gabriel Castillo,

Thanks for your question.

Try the following as torubleshooting steps to pindown the issue:

Check Docker network configuration

docker network ls
docker network inspect bridge

Inspect the specific container's network details

docker inspect <container_name>

Verify DNS configuration inside the container:

cat /etc/resolv.conf

Test network connectivity from the host itself to see if its a host issue

ping 8.8.8.8
ping google.com

Also see the stackoverlow post for an ubuntu machine https://stackoverflow.com/questions/73313328/how-to-troubleshoot-docker-network-issues

You can mark it 'Accept Answer' and 'Upvote' if this helped you

Regards,

Abiola

Answer 2

Hi @Gabriel Castillo,

Thank you for your patience.Run command: sudo su

Once docker image building is finished: docker build -t <imagename> . then run the Docker Container: docker run -d -p 80:80 --name <containername> <imagename>

Run command: docker exec -it <containerID> /bin/bash

apt-get update

apt install iputils-ping

Try ping google.com and check whether you are able to connect.

If you have any further queries, do let us know. We are happy to assist you.