Rpis and connman are providing multiple DUIDs to dhcpv6 server

Help and Support
21

Last observation on my side: nslookup pi4 returns my slaac addresses not my dhcpv6 ones, and the documentation says If the setting is "auto", then SLAAC or DHCPv6 is used.

So connman probably doesn’t handle SLAAC and DHCPv6 both concurrently, does one and then the other and the last one done imposes configuration and settings file content (slaac in my case and dhcp in @JimKnopf case)…

22

ConnMan has a mailing list connman@lists.linux.dev here: connman.lists.linux.dev archive mirror

Please copy me in to any bug reports.

23

I’m not sure. I’ve only few configuration settings of the DHCPv6 on the Fritz!Box:

  • Router Advertisment - is set to assign the ULA prefix always
  • DHCPv6 is set to “DNS only”

So, the Pi gets the IPv6s via SLAAC built by the router advertisments (you see the inner FF:FE surrounded by the MAC link interface in the interface-identifier part).

But even if I set DHCPv6 to “DNS, assign IA_PD prefix” or “DNS, assign IA_PD and IA_NA” I see the DUID in the settings file.

24

using support at osmc dot tv ?

Never mind saw your message in my inbox !

25

Thanks, I got the emails.

26

@sam_nazarko I saw armv7-connman-osmc/inconnu 1.41-2 armhf was available so I tested it.

Seems you decided not to implement the DUID modification (use a DUID_LL instead of a DUID_LLT).
Could you (as with the previous version) make a modifiied version available please ?

Regards

27

I was waiting for an update on the ConnMan mailing list before including any changes.

28

Hello, more than a year later, and I’ve also been hit by this problem, but this time in a Vero V. The DUID changed every restart or reboot, defeating the whole purpose of a DUID, until I installed the connman version from here. I still don’t have a DUID in the settings, but at least it look stable in the DHCP server:

root@osmc:/home/osmc# cat /var/lib/connman/ethernet_94cc04600751_cable/settings
[ethernet_94cc04600751_cable]
Name=Wired
AutoConnect=true
Modified=2026-02-08T17:07:25Z
IPv4.method=dhcp
IPv4.DHCP.LastAddress=192.168.20.10
IPv6.method=auto
IPv6.privacy=prefered
IPv6.DHCP.LastAddress=fd65:5d32:50d:fd02::5c0

It also fixed the privacy extensions for IPv6, which weren’t working before.

May I ask why this fix is not deployed in the main repo? And more important, why connman? I’ve only have had problems with it. This thing, the privacy extensions, the fact that you cannot set a MTU, etc.

29

I will chase this shortly. I was hoping to get an update on it being included upstream.

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