Re: [libvirt] macvtap - no incoming ipv6 traffic processed on kvm host unless i start tcpdump on interface

I could narrow down the problem. Win7Prof and Windows 10 is having this issue. Win Client is member of the multicast group and is listening on ff02::1:ffdf:fe88 Traffic from router -> client - captured on router: 07:41:23.104567 IP6 fe80::12fe:edff:fee6:cfa > ff02::1:ffdf:fe88: ICMP6, neighbor solicitation, who has 2a01:198:200:8350:851e:21a7:28df:fe88, length 32 07:41:24.099764 IP6 fe80::12fe:edff:fee6:cfa > ff02::1:ffdf:fe88: ICMP6, neighbor solicitation, who has 2a01:198:200:8350:851e:21a7:28df:fe88, length 32 07:41:25.099772 IP6 fe80::12fe:edff:fee6:cfa > ff02::1:ffdf:fe88: ICMP6, neighbor solicitation, who has 2a01:198:200:8350:851e:21a7:28df:fe88, length 32 Traffic from router to client - captured on KVM HOST 09:41:23.106444 IP6 fe80::12fe:edff:fee6:cfa > ff02::1:ffdf:fe88: ICMP6, neighbor solicitation, who has 2a01:198:200:8350:851e:21a7:28df:fe88, length 32 09:41:24.101647 IP6 fe80::12fe:edff:fee6:cfa > ff02::1:ffdf:fe88: ICMP6, neighbor solicitation, who has 2a01:198:200:8350:851e:21a7:28df:fe88, length 32 09:41:25.101718 IP6 fe80::12fe:edff:fee6:cfa > ff02::1:ffdf:fe88: ICMP6, neighbor solicitation, who has 2a01:198:200:8350:851e:21a7:28df:fe88, length 32 No traffic seen on KVM GUEST (win7 or win10) with wireshark Any ideas to debug this further? Cheers Stefan