avahi-autoipd

avahi-autoipd [ -D ] [ -c interface] [-k] [ -g group] [ -u user] [ -s subnet] [ -t timeout ] interface

-D
    Do not detach from terminal

-c interface
    The network interface to use.

-k
    Keep old address (use SIGHUP to release it). By default addresses are released before the process quits.

-g group
    Change to this group ID after initialization.

-u user
    Change to this user ID after initialization.

-s subnet
    Subnet to use, instead of 169.254.0.0

-t timeout
    Timeout to use in seconds, instead of 30

interface
    Specifies the network interface the daemon should operate on.

The avahi-autoipd daemon is a component of the Avahi system that automatically configures IPv4 link-local addresses on a network interface when a DHCP server is not available. This is done according to the Zeroconf standard. It listens for address conflicts and attempts to claim an address or withdraw if another host uses the same address.

It is particularly useful in small networks where a DHCP server is not present, allowing devices to communicate with each other without manual IP address configuration. avahi-autoipd greatly simplifies network setup by automating the address assignment process. The daemon typically runs in the background and requires minimal user intervention. The core functionality involves probing the network to find an available address and claiming it. If a conflict arises, the daemon attempts to resolve it or relinquishes the address.

avahi-autoipd assigns an address within the 169.254.0.0/16 range, which is reserved for link-local addressing. This range may not be routable across different networks without additional configuration.

avahi-autoipd returns 0 on successful completion, and non-zero on error. Error conditions include failing to claim an address after several retries or encountering issues with the network interface.

Sending SIGHUP will release address if -k wasn't specified.

avahi-autoipd is derived from the original autoipd implementation. It was incorporated into the Avahi project to provide better integration with other Avahi services, specifically its multicast DNS implementation. Its development focuses on ensuring reliable address assignment in environments lacking DHCP servers, facilitating seamless peer-to-peer communication. Its usage has grown with the adoption of Zeroconf networking in various embedded devices and small networks.

avahi-daemon(8), ifconfig(8), dhclient(8)