2013/2/11 Rafał Miłecki <[email protected]>: > I've compiled two extra tools: tcpdump and arp. > > It seems that OpenWRT can't understand ARP response. See attached > tcpdump.and.ping.all.on.router.txt - it's a ping and tcpdump both > running on OpenWRT router. > > Router want to ping 192.168.1.2, so it's sending ARP request: > FF FF FF FF FF FF (dest) > C8 3A 35 40 C1 A8 (src) > 81 00 00 00 (vlan0) > 08 06 (arp) > > My PC replies to the request: > C8 3A 35 40 C1 A8 (dest) > 00 1D BA 19 9E DB (src) > 81 00 00 01 (vlan1) > 08 06 (arp) > > And... nothing! There isn't ICMP request sent by the router. I've > decided to check the arp table: > # arp > IP address HW type Flags HW address Mask Device > 192.168.1.2 0x1 0x0 00:00:00:00:00:00 * br-lan > > Is this the reason? Linux can't parse ARP response from the PC and > doesn't know it's MAC?
That theory makes even more sense after re-thinking it. When I ping router from my PC, there are three packets repeated over and over: 1) PC sends ICMP request 2) Router sends ARP requres 3) PC sends ARP reply but nothing more... Router seems to ignore/don't understand ARP reply and can't reply for ICMP request. Do you remember me saying that for a few seconds after doing brctl delif br-lan eth0 brctl addif br-lan eth0.0 I can still ping the router? It looks it could be thanks to the ARP cache. When using eth0 for br-lan router received and parsed ARP response. After a switching back to eth0.0 (from eth0) router was still using arp cache table until it expired. Make sense to me. The only question... WHY router can't understand ARP responses over br-lan connected to eth0.0? :( -- Rafał _______________________________________________ openwrt-devel mailing list [email protected] https://lists.openwrt.org/mailman/listinfo/openwrt-devel
