Docker fix for SSL issues due to corporate network

Goal

Docker may fail to resolve DNS addresses on a network that uses proxy servers, such as a corporate network. This will manifest itself as an error when running docker-compose build commands and look something like this:

---> Running in 371637437e86
/tmp/download-kafka.sh: line 3: jq: not found
/tmp/download-kafka.sh: line 3: curl: not found
wget: bad address 'kafka'
ERROR: Service 'kafka' failed to build: The command '/bin/sh -c chmod a+x /tmp/download-kafka.sh && sync && /tmp/download-kafka.sh && tar xfz /tmp/kafka_${SCALA_VERSION}-${KAFKA_VERSION}.tgz -C /opt && rm /tmp/kafka_${SCALA_VERSION}-${KAFKA_VERSION}.tgz' returned a non-zero code: 1

This can be fixed by manually overriding where Docker looks for the system DNS server.

Procedure

1. Find the address of your DNS server.

Run nslookup www.google.com and you will see an output like this:

$ nslookup www.google.com
Server:		192.168.1.1
Address:	192.168.1.1#53

Note the address that appears (192.168.1.1 in this case).

2. Tell Docker where to look for DNS server.

Create a new daemon.json file in your /etc/docker directory containing the following info. Replace the 192.168.1.1 with the address found in step 1. The 8.8.8.8 address should not be changed, this is the default Docker DNS address.

{"dns": ["192.168.1.1", "8.8.8.8"]}

A simple way to create this file is to run a command like this:

echo '{"dns": ["192.168.1.1", "8.8.8.8"]}' > /etc/docker/daemon.json

If you get a permissions error, rerun the command with sudo in front.

3. Restart the Docker daemon

sudo service docker restart

Running docker-compose up --build -d should now create and start the containers without any build issues.

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Reference

Reference: https://robinwinslow.uk/2016/06/23/fix-docker-networking-dns/