On Tue, Oct 13, 2015, at 08:47, Jörg Pommnitz wrote: > Hello all, > I'm moving an application from 2.6.23 (yes, it's ancient; that's why > we are moving) to 3.18LTS. The application monitors multiple network > links to the same target with ping packets. The different links are > selected either by their next hop router (Ethernet) or the network > interface (Point-to-Point links, aka cellular data). > To force different routes to the same target, the outgoing packets are > tagged with different firewall marks. Then I'm using routing rules to > select different routing tables with different routes for the same > target. > The outgoing path works perfectly fine in both, 2.6.23 and 3.18. > However, the same is not true for the incoming ICMP replies. They are > incoming; I see them with tcpdump. But some packets do not get > delivered to user space in 3.18. I'm not 100% sure, but I think this > happens if there is no "normal" route to the ping target, e.g. the > source address of the ICMP replies. This looks like some kind of > misguided ingress filtering that keeps packets out if a normal routing > lookup fails. > > Am I on the right track? If so, is there a way to disable this > filtering? If not, what could cause this changed behaviour?
Did you disable rp_filter? Sounds like it, but 2.6.23 also had it activated by default, so maybe you missed the option in sysctl.conf. Bye, Hannes -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
