IIRC, it is not quite a noop, but a logical AND between the two? Or maybe it was an OR. I'm pretty sure now the 'forwarding' setting was an OR between all & interface (but, some other setting was an AND). I might be wrong though. Anyway, different net.ipvx.conf settings have different rules, and it is frankly confusing as duck. But they aren't "broken" nor "ignored", no. -- Mantas Mikulėnas <div class="gmail_quote">On Jun 8, 2015 23:00, "Lennart Poettering" <<a href="mailto:lennart@poettering.net">lennart@poettering.net</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Wed, 03.06.15 19:18, Sébastien Luttringer (<a href="mailto:seblu@seblu.net">seblu@seblu.net</a>) wrote: > Hello, > > Since systemd v220, IPForward= parameter in [Network] set kernel > parameters by interface (/proc/sys/net/ipv[46]/conf/*/forwarding). > This is nice and works perfectly for ipv4. > > Unfortunately, ipv6 forwarding doesn't works until we manually set > /proc/sys/net/ipv6/conf/all/forwarding to 1. Are you saying that /proc/sys/net/ipv6/conf/$interface/forwarding is a NOP in the kernel for anything except $interface being "all"? That sounds seriously broken in the kernel. They should not expose a setting that is a NOP like that... > > In term of user experience, IPforward=ipv6 doesn't enable ipv6 > forwarding on the interface. That's tricked me. > > From: > <a href="https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt" target="_blank">https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt</a> > > conf/all/forwarding - BOOLEAN > Enable global IPv6 forwarding between all interfaces. > > IPv4 and IPv6 work differently here; e.g. netfilter must be > used > to control which interfaces may forward packets and which not. > > An maybe better explained here: > <a href="http://www.tldp.org/HOWTO/Linux+IPv6-HOWTO/proc-sys-net-ipv6..html" target="_blank">http://www.tldp.org/HOWTO/Linux+IPv6-HOWTO/proc-sys-net-ipv6..html</a> This documentation is not particularly good, but it certainly doesn't suggest the option was a NOP. Can you elaborate on this? Do you have any references that clarify that IPv6 and IPv4 handling of this setting is really different? Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list <a href="mailto:systemd-devel@lists.freedesktop.org">systemd-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/systemd-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/systemd-devel</a> </blockquote></div>