radns is a small, portable client-side implementation of the RDNSS option in IPv6 Router Advertisements (RFC 5006) that is used to get the address of a resolving DNS server. It listens for Router Advertisements with the Recursive DNS Server (RDNSS) option and stores the addresses in a file following the same syntax as resolv.conf. It optionally calls a script to handle, for instance, DHCP clients that compete for ownership of /etc/resolv.conf or to set the DNS server on systems that don't use resolv.conf at all. It can be easily integrated with the resolvconf(8) program.
