avahi-dnsconfd

Unicast DNS server configuration daemon using mDNS

TLDR

Start the DNS configuration daemon

$ avahi-dnsconfd

Start as a background daemon

$ avahi-dnsconfd --daemonize

Start with syslog logging

$ avahi-dnsconfd --syslog

Kill a running instance

$ avahi-dnsconfd --kill

Refresh DNS server data (send SIGHUP)

$ killall -HUP avahi-dnsconfd

avahi-dnsconfd is a daemon that configures unicast DNS servers based on mDNS/DNS-SD announcements on the local network. It connects to a running avahi-daemon and monitors for DNS server announcements.When a unicast DNS server is announced or removed from the network, avahi-dnsconfd executes the action script /etc/avahi/avahi-dnsconfd.action to update the system's DNS configuration. This provides DHCP-like DNS server discovery using mDNS.The daemon requires avahi-daemon to be running. It is useful in environments where DNS servers are dynamically announced via Zeroconf/Bonjour protocols rather than configured through traditional DHCP.

PARAMETERS

-D, --daemonize

Run as a background daemon and log to syslog

-s, --syslog

Log to syslog instead of stderr

-k, --kill

Kill an already running avahi-dnsconfd instance

--refresh

Refresh DNS server information

--check

Check if daemon is running

-h, --help

Display help message

-v, --version

Show version information

CONFIGURATION

/etc/avahi/avahi-dnsconfd.action

Shell script executed when DNS servers are discovered or removed on the network. Receives action type and DNS server address as arguments.

SIGNALS

SIGINT, SIGTERM

Shutdown the daemon

SIGHUP

Refresh DNS server data

INSTALL

sudo apt install avahi-dnsconfd

sudo dnf install avahi-dnsconfd

sudo pacman -S avahi

sudo apk add avahi

sudo zypper install avahi

brew install avahi

nix profile install nixpkgs#avahi

CAVEATS

Requires avahi-daemon to be running first. The action script must be properly configured to update DNS resolver settings. May conflict with other DNS management tools like NetworkManager or systemd-resolved if not properly integrated.

HISTORY

Avahi was created by Lennart Poettering and Trent Lloyd starting in 2005 as a free implementation of Zeroconf/mDNS/DNS-SD for Linux. The avahi-dnsconfd component was designed to integrate zero-configuration DNS server discovery with traditional unicast DNS resolution, allowing networks to operate without manual DNS configuration.