zonefilegen

A simple tool to generate synchronized forward and reverse DNS zone files based on an input text file.

The intended use case is where a local authoritative DNS server is used to serve lookups for hosts confined within a single forward DNS zone. Thus, only a single forward zone is supported in order to simplify the input file.

Reverse zones will be generated for specified subnets, and they will be automatically populated with PTR records corresponding to the first A and AAAA records found in the input file for a certain host.

Zone serial numbers will automatically be incremented when the input file has changed.

Installation

Install via pip:

pip install zonefilegen

Usage

The package installs a command line tool zonefilegen which generates zone files in a specified directory based on an input file:

zonefilegen input.toml output_folder

This will parse input.toml and generate one forward zone file and zero and more reverse zone files in output_dir.

Input file format

The input file is written in the TOML format which is easy to read by both humans and machines.

For an example file, see docs/sample.toml.

Required entries

The following entries are required in the input file:

• origin: The FQDN of the forward DNS zone. $ORIGIN in the zone file.

• default_ttl: Default TTL for resource records if they have none set. $TTL in the zone file.

• [soa]: Contains the entries to put in the SOA record, except for the serial number:

  • mname
  • rname
  • refresh
  • retry
  • expire
  • negative_caching_ttl

• One or more [[rrset]] with entries for the forward records. Each [[rrset]] entry contains one or more records with the same name, type and ttl value:

  • name: @, unqualified name or FQDN.
  • type: The record type like A or MX.
  • ttl: Optional TTL value.
  • data: A string or a list of strings with the record data. A separate record will be created for every string in the list.

Optionally, one can also supply a networks entry, which should contain a list of networks in CIDR notation (ipv4 or ipv6) for which reverse zones should be created. The networks must end on whole-octet (ipv4) or whole-nibble edges (ipv6). So only /16, /24 etc in the ipv4 case and /48, /52, /56 etc for ipv6.