On Mon, Aug 20, 2018 at 7:55 AM Andy Smith <a...@strugglers.net> wrote: > > Hi Martin, > > On Mon, Aug 20, 2018 at 05:12:56AM +0300, Martin T wrote: > > According to "man interfaces" "accept_ra 1" makes interface to accept > > IPv6 RA messages. "accept_ra 2" does the same and in addition, it also > > enables forwarding. What does the forwarding mean in this context? One > > could think, that it modifies the /proc/sys/net/ipv6/conf/*/forwarding > > file(s), but this does not seem to be the case. > > If forwarding = 1 then by default RAs will not be accepted. Setting > accept_ra to 2 allows RAs to be accepted even when forwarding = 1. > > Changing the values of either forwarding or accept_ra does not alter > the values of the other. Only the behaviour of the system. > > Back in 2011 this was a hard-won battle: > > > http://strugglers.net/~andy/blog/2011/09/04/linux-ipv6-router-advertisements-and-forwarding/ > > Cheers, > Andy >
Hi Andy! Thanks for this very informative blog post! However, setting the "net.ipv6.conf.all.forwarding" to 1 in /etc/sysctl.conf and "accept_ra" to 2 in /etc/network/interfaces for ISP facing interface(eth0) didn't work for me. I expected SLAAC to work, but it didn't. I'm running kernel version 4.9.0. Settings can be seen below: # sysctl net.ipv6.conf.all.forwarding net.ipv6.conf.all.forwarding = 1 # # sysctl net.ipv6.conf.eth0.accept_ra net.ipv6.conf.eth0.accept_ra = 2 # When I set the "net.ipv6.conf.all.forwarding" to 0 and reboot the router, then SLAAC works. What might cause this? thanks, Martin
