From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-4316.protonmail.ch (mail-4316.protonmail.ch [185.70.43.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A60D03F0ABD for ; Fri, 29 May 2026 18:29:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.70.43.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780079357; cv=none; b=d7oZoV0wWcLkT+fYOT72wiBlOUPlLiPLQOrMdYxOEFc6Tk9SDI5EKisDL4YLLhu1APDCl8BjwL9C8C+hIMC9YoiB7htLqSzXedT2RcEd+J6GUfWsp6UqGFbXpL/5OozX4d3GafxtYaT39nnQqUmbHs8DhVDUDvH5/ZVU1xv9AQM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780079357; c=relaxed/simple; bh=BjWqTyDxUdfqE14VFV8iw+Ji/gfyO9phtRw98i7w+W4=; h=Date:To:From:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=AnygP+5kqN8uwk8m3Y8Z7jczIdlaaod4vYGem3Dsjva3xtawHtmibdOPa/6oxLQU7YR7vWP4Sl54LxBZueXuQ+srJvuscKjZngh4HybLinLl09aUjBq1VPUn37oqQflTfPjHwEM4ylxXV8SJEfB/pR1kS2HbwQN1kv6ro2CBfrE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=proton.me; spf=pass smtp.mailfrom=proton.me; dkim=pass (2048-bit key) header.d=proton.me header.i=@proton.me header.b=Zef24QeX; arc=none smtp.client-ip=185.70.43.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=proton.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=proton.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=proton.me header.i=@proton.me header.b="Zef24QeX" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=arxro2oaarh5havr3xqobzkzcy.protonmail; t=1780079351; x=1780338551; bh=K4HabgLRlspjLKXF/1Q9wzXeGtbAyDxSqL9Ju2E8DMI=; h=Date:To:From:Cc:Subject:Message-ID:Feedback-ID:From:To:Cc:Date: Subject:Reply-To:Feedback-ID:Message-ID:BIMI-Selector; b=Zef24QeXyhjaeZyqqsMdLsylngM9OMyGPQRhbt1BgaRjNE34VezaGvZcF0tFZud3t MGT4BswqNXQi0vaafhhnvF76MxWqQITVGsUxCBr9qwThJhPTANPppfFqR9JbsCD983 TTUAoQ7MKp7Yqd7gv4aHblMp72HkfgyivhqwbKZoj8XpawQhRGUV5E97dRb/UeAsrs T9ULpEZBUe1jNWrAjg/8aOdzIbidajIV9gZMI+XbsUW+aKWXXUOD9eaO9vMyYaxJ+5 b91WorbDAh8DHNHfEXsj5DomPCm203UHCCTeMz5EUw0jFlPYPg+5VVB4L+nAdSfER+ 4wIraCFazfWdg== Date: Fri, 29 May 2026 18:28:58 +0000 To: =?utf-8?Q?=C3=8D=C3=B1igo_Huguet?= , Stefano Brivio From: Tj Cc: Thorsten Leemhuis , Fernando Fernandez Mancera , Jakub Kicinski , netdev@vger.kernel.org, Yumei Huang , Ido Schimmel , Justin Iurman , David Ahern , David Gibson , Linux kernel regressions list , Beniamino Galvani Subject: Re: Problem with IPv6 privacy addresses in 7.0 Message-ID: Feedback-ID: 113488376:user:proton X-Pm-Message-ID: 5166abbb1ff849044137cccbb7fe39bb5fa1386a Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable I believe I hit this on a router using Debian 13 with v7.0.* kernel this we= ek that uses systemd-networkd to configure IPV6 RA and prefix delegation after moving from v6.19.*. Symptom was the router could no longer reach public IPv6 addresses itself but forwarding was unaffected. The ISP (Starlink) provides a /64 prefix via RA and a /56 via DHCPv6. netwo= rkd allocates a static suffix address from both to the WAN-side interface. I discovered after much experimentation that instead of the usual /56 address being the source it was choosing the /64 and failing. Router uses policy routing so my work-around was to add a rule so the /64 address is added to the WAN interface's route table. [RoutingPolicyRule] To=3D::/0 From=3D2a0d:3344:aaaa:bbbb::/64 Priority=3D30100 Table=3Dstarlink The WAN interface config for RA and PD is: [IPv6AcceptRA] UseGateway=3Dyes UseDNS=3Dno UseDomains=3Dno Token=3Dstatic:::ff # when RouteTable is set a table name is explicitly required in any [Route]= section without a Table=3D of its own # names defined in /etc/systemd/networkd.conf.d/51-RouteTable.conf as: [Ne= twork] RouteTable=3D RouteTable=3Dstarlink [DHCPv6] UseAddress=3Dno UseDNS=3Dno UseNTP=3Dno UseHostname=3Dno UseDomains=3Dno UseDelegatedPrefix=3Dyes PrefixDelegationHint=3D::/56 ## asked for in RFE https://github.com/systemd/systemd/issues/31566 ##RouteTable=3Dstarlink [DHCPPrefixDelegation] Announce=3Dfalse UplinkInterface=3D:self Assign=3Dyes Token=3Dstatic:::1 SubnetId=3D0xff