Date: Thu, 26 Nov 2015 20:47:52 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 204831] mld_v2 listener report does not report all active groups to the router Message-ID: <bug-204831-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=204831 Bug ID: 204831 Summary: mld_v2 listener report does not report all active groups to the router Product: Base System Version: 9.3-STABLE Hardware: amd64 OS: Any Status: New Severity: Affects Some People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: scheffler@beuth-hochschule.de Created attachment 163558 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=163558&action=edit Wireshark trace When using applications that receive traffic from a rather large number (510) multicast groups, traffic from some groups is lost after time. Reception for all groups starts fine, but after a Multicast General Querry has been received from the on-link router, FreeBSD starts to loose lower numbered groups in the Multicast Listener Report Message. 'ifmcstat' shows all Groups are still active, but they are no longer reported to the router and therefore traffic is no longer forwarded to the receiver. This behaviour has first been observed on a FreeNAS using vnet, but could be replicated on a FreeBSD 9.3 with the latest patches (FreeBSD 9.3-RELEASE-p24). I include a Wireshark trace that shows the behaviour. Starting with packet 35 all 510 groups are reported. However, in packet 42 the reporting does not stop at the last group and all groups are reported again. This continues until we see in packet 62 that the first multicast groups are lost: ff15::1001:39 - ff15::1001:1 The loss contiues to grow until we have lost the first 221 groups, where it stays stable. In order to replicate the behaviour, an active Multicast Router is required on the link (it seems to be triggered by the reception of the General Querry Message from the router). The behaviour can not be seen, when no router is present. I used mgen and a simple c-programm to verify the behaviour. If needed, I can supply the testprogam. -- You are receiving this mail because: You are the assignee for the bug.
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