http://marc.info/?l=openbsd-misc&m=141703607321548&w=2 -- Josh Smith KD8HRX
Email/jabber: juice...@gmail.com Sent from my iPhone. > On Dec 31, 2014, at 2:01 PM, Aaron Riekenberg <aaron.riekenb...@gmail.com> > wrote: > > I have an OpenBSD 5.6 box that I'm using as a router and firewall for my > local LAN, using both ipv4 and ipv6. Things are mostly working, but I'm > seeing some possibly broken/annoying behavior from rtadvd. First some > background information: > > My box has 2 ethernet interfaces: em0 is the external connection, and em1 > is the local LAN. Comcast provides ipv6 router advertisements and uses > dhcpv6 to provide a /128 address (used by em0) and a /64 prefix delegation > used by my local LAN. I'm using wide-dhcpv6 to assign addresses to my em0 > and em1 and this all works fine. > > I have the issue that if net.inet6.ip6.forwarding=1, the kernel is not able > to automatically configure the default ipv6 route based on router > advertisements, even with the new "inet6 autoconf" parameter ( > http://permalink.gmane.org/gmane.os.openbsd.misc/217825). > > To work around this, I temporarily ran rtsold, figured out the ipv6 address > of Comcast's router, and added it to /etc/mygate. This works fine, and I > am no longer running rtsold. > > Now I run "rtadvd em1" to send router advertisements to the local LAN. I > have no /etc/rtadvd.conf file, so I am using the default configuration. > This again works fine, and hosts on my local LAN automatically get an ipv6 > address and route (yay!). > > But all is not quite perfect. If I look at /var/log/daemon, I see lots and > lots of messages from rtadvd like this: > > Dec 31 12:44:21 server rtadvd[28960]: received RA from > fe80::224:14ff:fe63:cae2 on non-advertising interface(em0) > Dec 31 12:44:54 server last message repeated 11 times > Dec 31 12:46:56 server last message repeated 40 times > Dec 31 12:51:32 server last message repeated 90 times > > This is saying rtadvd received a router advertisement from Comcast's router > (fe80::224:14ff:fe63:cae2). Comcast's router apparently sends on of these > every 3 seconds - this is the rate at which syslog is filling with these > messages. > > I can disable logging for rtadvd in syslog.conf, but this is annoying. > There are potentially many others like me with Comcast or other ipv6 > connections that want to run rtadvd on the internal interface and will > receive router advertisements on the external interface. > Thoughts/questions: > > * Why is rtadvd logging router advertisements on em0 when I am specifying > em1 as the only interface it should be using? Wouldn't it be better to > just silently ignore router advertisements from non-configured interfaces? > * What will happen when/if we can have net.inet6.ip6.forwarding=1 and > "inet6 autoconf" for my external interface? Will rtadvd still receive > router advertisements for the external interface and complain about them?
