Configuring the Docker container DNS

If Docker runs on a virtual machine (Docker for Mac, Docker for Windows), the default container DNS configuration differs from the one of the physical machine. In that case you need to configure the DNS in the Docker configuration file provided with the Remote Engine Gen2.

1. Go to the Remote Engine Gen2 installation directory and open the following file to edit it:
   default/docker-compose.yml if you are using the engine in the AWS USA, AWS Europe, AWS Asia-Pacific or Azure regions.

   eap/docker-compose.yml if you are using the engine as part of the Early Adopter Program.

2. To configure:
   1. dynamic DNS resolution, add name servers in a dns section, or add suffixes in a dns_search section. Suffixes will be appended to host names automatically for DNS resolution. The entries listed in the dns_search section will appear in the /etc/resolv.conf file of each container.

      Example

      dns:
        - 8.8.8.8
        - 9.9.9.9
      dns_search:
        - dc1.example.com
        - dc2.example.com

   2. static DNS resolution, add entries in a extra_hosts section. These entries will be automatically added to the /etc/hosts file of each container.
      Information noteNote: Two Remote Engine Gen2 containers, livy and component-server, require external connections so the DNS configuration might be needed for both of them.

      Example

      extra_hosts:
       - "somehost:162.242.195.82"
       - "otherhost:50.31.209.229"

3. Save the file.

version: '3.6'

networks: ...

volumes:...

services:
 ...
 component-server:
  image: ${COMPONENTS_IMG}
  ...
  labels:...
  dns:
  - 8.8.8.8
  - 9.9.9.9
  dns_search:
  - dc1.example.com
  - dc2.example.com  
  extra_hosts:
  - "somehost:162.242.195.82"
  - "otherhost:50.31.209.229"
...