From: "Sven F." <sven.falempin@gmail.com>
Subject: non-perfect diff to explain an issue with netstart and AUTOCONF
To: tech@openbsd.org
Date: Fri, 30 May 2025 12:18:31 -0400

Dear readers.

If an interface is configured with AUTOCONF
hostname.if does not remove the flag

hence removing autoconf and putting inet something
in hostname.if and then restarting the network makes...unexpected
result
( interface will have static inet config and dhcp config )

This "solution" works, but the logic flow may be problematic

--- /etc/netstart.orig  Fri May 30 12:12:49 2025
+++ /etc/netstart       Fri May 30 12:14:29 2025
@@ -52,6 +52,7 @@
                        V4_AUTOCONF=true
                        return
                fi
+               ifconfig $_if -autoconf
                [[ ${_c[_name]} == alias ]] && _mask=3 _bc=4
                [[ -n ${_c[_mask]} ]] && _c[_mask]="netmask ${_c[_mask]}"
                if [[ -n ${_c[_bc]} ]]; then
@@ -66,6 +67,7 @@
                        V6_AUTOCONF=true
                        return
                fi
+               ifconfig $_if -autoconf
                [[ ${_c[_name]} == alias ]] && _prefix=3
                [[ -n ${_c[_prefix]} ]] && _c[_prefix]="prefixlen
${_c[_prefix]}"
                _cmds[${#_cmds[*]}]="ifconfig $_if ${_c[@]}"

Best

Tested on 7.7 stable