I'm writing an application which receives multicast data. The machine which runs the application has several network interfaces, however the multicast data comes in only on one of them. My problem is that my program subscribes to the mcast group on that interface, but then isn't able to receive any data, UNLESS that interface happens to be eth0. My program is binding the correct ports (fast1.st is the name associated with eth1): fast1:~# netstat -ap | grep mcast udp 0 0 *:53561 *:* 640/mcastjoin And has subscribed to the appropriate mcast group on the right interface: fast1:~# netstat -g IPv6/IPv4 Group Memberships Interface RefCnt Group --------------- ------ --------------------- lo 1 ALL-SYSTEMS.MCAST.NET eth0 1 ALL-SYSTEMS.MCAST.NET eth1 1 224.0.2.218 eth1 1 ALL-SYSTEMS.MCAST.NET And there's data coming in on that interface: fast1:~# tcpdump -i eth1 ip multicast | grep 224.0.2.218 tcpdump: listening on eth1 15:36:34.798668 198.140.60.177.49328 > 224.0.2.218.53561: udp 801 15:36:35.098871 198.140.60.177.49328 > 224.0.2.218.53561: udp 910 15:36:35.099371 198.140.60.177.49328 > 224.0.2.218.53561: udp 822 15:36:35.100370 198.140.60.177.49328 > 224.0.2.218.53561: udp 896 This is a vanilla kernel 2.4.27 with OpenAFS, otherwised unpatched. What might I be doing wrong? Thanks. Wes -- http://www.woahnelly.net/~wes/ OpenPGP key = 0xA5CA6644 fingerprint = FDE5 21D8 9D8B 386F 128F DF52 3F52 D582 A5CA 6644 - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
