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charset=us-ascii Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.34 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Technical discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 25 Apr 2021 10:20:46 -0000 Hello hackers, For IPv6 there's RFC 6724 to clarify the default address selection = procedure,=20 both for source address selection and destination address selection. Are = there any RFCs like RFC 6724 that are for IPv4?=20 I'm exploring RFC 3927, consider this situation, a host configured with = link-local address on NIC and global unicast alias address on loopback interface, = and default route to=20 the link-local address of router (some ISPs do this). The current = implementation kernel will use the link-local address as the source address when initializing = a connection to=20 remote host via the default route. It seems wrong, as link-local address = are not=20 routable as per RFC 3927. So it is important if there's corresponding RFC clarify the source = address selection=20 for IPv4. Thanks :)=