On Thu, Dec 21, 2023 at 04:51:37PM +0000, Gary Buhrmaster wrote:
On Wed, Dec 20, 2023 at 7:51 PM Chris Adams <linux(a)cmadams.net>
wrote:
>
> Once upon a time, Aoife Moloney <amoloney(a)redhat.com> said:
> > Enable IPv4 Address Conflict Detection by default in NetworkManager.
>
> Huh, I didn't realize NM didn't already do this... ye olde
> network-scripts did.
>
As I recall, depending on configuration(s),
systemd-networkd has done so for quite
some time. Off hand I do not recall its
various values, but it might make sense
to align the settings.
systemd-networkd supports DAD for both static and dynamic addresses,
and it's disabled by default. For static addresses, DAD must be
enabled via:
[Address]
Address=192.168.1.1/24
DuplicateAddressDetection=ipv4
For DHCP, it is enabled by setting Dhcpv4.SendDecline=true
In both cases, the maximum timeout is the one from RFC 5227 (9
seconds) and it's not configurable. I have filed an issue to make the
value configurable:
https://github.com/systemd/systemd/issues/30724
Beniamino