troglobit / mdns-alias

mDNS-SD CNAME Publisher in C

Publish mDNS-SD Aliases

This is a small C program that publishes mDNS CNAMEs using Avahi. It runs as a UNIX daemon, ensuring the CNAME records are published as long as the daemon runs.

Currently the program takes its CNAME aliases on the command line:

mdns-alias foo.local bar.local

At least one name, including .local, must be given on the command line.

Dependencies

At run time: a running avahi-daemon

Build time: avahi client library and header files, and to detect it, the pkg-config tool. You also need a C compiler and make.

Ubuntu, Mint, or other Debian based Linux distributions:

sudo apt install libavahi-client-dev pkg-config

Building

This project is built using configure and make. The configure script generates the Makefile for your host system, or your embedded target system. Usually setting --host=toolchain-prefix- is all you need for the configure script to find your cross compiler.

./configure
make

By default the configure script prepares for installing in /usr/local, if you want to change that, please see ./configure --help. To install type:

sudo make install

Some systems no longer have sudo, alternatives include su to root, or tools like doas.

Note: if you do not like pre-packaged, and properly versioned, release tarballs, you need to have GNU autoconf and automake installed to be able run the autogen.sh script. It creates the configure script and Makefile template, which are included in the portable release tarballs.

Motivation

For some reason the de facto standard mDNS-SD daemon in Linux, Avahi, does not support CNAME (DNS alias) records in the configuration files or using any of its tools. This has been covered in many repos, but none did it better than George Hawkins, I believe.