Date: Fri, 16 Dec 2005 23:57:44 +0000 (GMT) From: Nate Nielsen <nielsen-list@memberwebs.com> To: freebsd-net@freebsd.org Subject: Multicast packets dropped on atheros wireless link Message-ID: <20051216235743.E0E1A70DDA4@mail.npubs.com>
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Certain multicast packets are not making it through an Atheros based 802.11 wireless link. Other drivers/cards (ie: wi) work fine. Two boxes sitting next to each other running FreeBSD 6.0. The cards are set up simply: ifconfig ath0 inet 172.28.2.18/30 ssid tel2 channel 52 \ mediaopt adhoc An OSPF daemon is running on both sides of the wireless link, causing multicast packets to be sent over the ath0 NICs on both boxes. The multicast packets link local multicast (ie: not routeable multicast). Although I'm using OSPF it seems any multicast packets would have the same behaviour. Running 'tcpdump -pnti ath0' on the first box (which indicentally is the BSSID for the adhoc link) shows packet pairs like this: > IP 172.28.2.18 > 224.0.0.5: OSPFv2, Hello, length: 48 > IP 172.28.2.17 > 224.0.0.5: OSPFv2, Hello, length: 44 > IP 172.28.2.18 > 224.0.0.5: OSPFv2, Hello, length: 48 > IP 172.28.2.17 > 224.0.0.5: OSPFv2, Hello, length: 44 These are packets from both OSPF daemons showing up on the ath0 NIC. This is the expected behaviour. However running 'tcpdump -pnti ath0' on the second box we see only: > IP 172.28.2.17 > 224.0.0.5: OSPFv2, Hello, length: 44 > IP 172.28.2.17 > 224.0.0.5: OSPFv2, Hello, length: 44 The packets from the BSSID box never make it over the wireless link. FWIW, setting up the two boxes as hostap/client mode doesn't fix the problem. The multicast packets from the hostap box aren't received on the client. Any ideas on where I should poke around? Cheers, Nate
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