I’m bringing up a new machine and it cannot receive multicast frames for some reason.
Everything else about the network seems to work fine.
Even multicast frame seems to get out fine because I can start
avahi-daemon and on startup I can see multicast going out on another computer on the same switch.
I have this which seems odd:
$ cat /sys/devices/pci0000:00/0000:00:1d.0/0000:58:00.0/net/enp88s0/statistics/multicast 0
tcpdump I get broadcast but no multicast:
$ sudo tcpdump -i enp88s0 -n multicast tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on enp88s0, link-type EN10MB (Ethernet), capture size 262144 bytes 14:04:02.076411 IP 192.168.2.56.9999 > 255.255.255.255.9999: UDP, length 29 14:04:17.839828 IP 192.168.2.15.9999 > 255.255.255.255.9999: UDP, length 29 14:04:18.013897 ARP, Request who-has 192.168.2.14 tell 192.168.2.15, length 46 14:04:21.826386 ARP, Request who-has 192.168.2.135 tell 192.168.2.135, length 46 14:04:26.014544 ARP, Request who-has 192.168.2.144 tell 192.168.2.144, length 46 14:04:31.272095 IP 192.168.2.55.9999 > 255.255.255.255.9999: UDP, length 29 ...
Any idea where this could be filtered?