Author: Greg Althaus

Level: Intro

Time: 5 minutes

 

Digital Rebar Platform has always provided for your data center infrastructure provisioning and day-two operations. Even though we provide DHCP services, file services, job tracking, machine state management, and much more provided with Infrastructure as Code (IaC) methodologies, DRP was missing something: a name server! A DNS server never made the feature cut list until now. What is in a Name (Server)? Let’s see!

 

How the new Digital Rebar DNS Server works

With release v4.13 and beyond, DRP includes a DNS Server. This is on by default and serves both UDP and TCP requests on port 53 by default. The normal server start-up flags can disable or alter the ports.

The basic element of configuration is the Zone object. The Zones work like an ordered list of evaluation checks to see if an answer should be returned. Zones allow for records, forwarders, and filters. Filters allow for answers to be altered based upon the source of the DNS request.

 

How to configure the DNS Server

First, the server can be configured as a simple forwarding name server. Adding a Zone with no records but defining the next DNS servers allow the system forward requests to get answers.

Second, the server can be configured to be a Zone that adds records to an existing Zone. This configuration allows for records to be defined but an additional set of DNS servers can be specified to get other records in the Zone. This is really useful for test environments.

Third, the server can be the traditional authoritative server for a Zone. Both success and negative answers are provided in this configuration.

As with all the DRP server components, they talk with each other. The Zone can be configured to dynamically create records based upon Machines and their parameters. Reservations and subnets that have options 12 and 15 configured will also generate records automatically.

 

Next Steps

Now, for what it isn’t. Sorry, the first pass implementation does not do DNSSEC. It can serve the records, but doesn’t handle record updates in this setup. AXFR and other zone transfers haven’t been fully supported. These may show up in a future release if we get interest. And don’t forget to check out everything else added in release v4.13!

For more information, check out these doc links.