It is not enough to set the INIT state after a NAK; a timeout
(ns_deferred) must be set so that it is added to the event fd. The
client retries immediately the first time, so that in the successful
case it gets an address quickly. To avoid flooding the network in case
of servers always replying with NAKs, next attempts are done with
intervals from 2 seconds to 5 minutes using exponential backoff. See
also systemd commit [1].
[1] 1d1a3e0afbhttps://gitlab.freedesktop.org/NetworkManager/NetworkManager/issues/325
218782a9a3