DNS

We use DNSControl to manage our external DNS Zones.

Getting Started

To make a change to a DNS Zone, follow the following steps.

1. Locate the Domain you want to modify within the domains folder.
   • For instance example.com records live within the domains/example_com.js file.
2. Locate the entry you wish to modify or an area with similar entries to the one you wish to add.
3. Make your changes or additions. A few examples can be found below.
4. Commit to branch, push, and create a pull request.
5. The changes will be reviewed and merged by admins.

Examples

A Record

    A('@', '192.168.1.1', CF_PROXY_ON),
    A('www', '192.168.1.1', CF_PROXY_ON)

CNAME Record

Note the trailing .. See Why trailing dot

    CNAME('dev', 'example.com.', CF_PROXY_ON)

Cloudflare CDN

The macros CF_PROXY_ON, CF_PROXY_OFF, and CF_PROXY_FULL control the use of CloudFlare CDN. Typically web hosted webapp use CF_PROXY_ON. This provides DDOS protection as well as caching and other security and traffic flow benefits. See.

Build and test

DNSControl can be run within Docker.

Running the following from the root folder will validate the dnsconfig.js file and report any errors during validation.

docker run --rm -i -v ${pwd}:/dns stackexchange/dnscontrol:latest dnscontrol check

When a PR is opened, the CI will run dnscontrol preview which describes changes (if any) which will be made and stops the build if any errors are found.