Bridge interface on VLAN not working

Ask Bjørn Hansen ask at develooper.com
Sat Jul 4 18:59:53 UTC 2020


Hi everyone,

I had this working for months until a reboot either got things started up in a different order or cleared what I setup by hand (it’s a snowflake test/development system at home) and did whatever I’d actually configured.

I have a single trunk’ed (em) interface to the switch. The main network is untagged, and I have various tagged networks as well.  I was using the tagged networks in bhyve virtual machines.

(Some?) traffic doesn’t pass from the bridged tap interfaces (or from the bridge itself) to the vlan interface (em0.8 for example).  tcpdump shows lots of packets coming from the “outside” and in, but for example if I do a ping from one of the tap interfaces then nothing shows up on the bridge interface (looking with tcpdump).

Another symptom is that if I move the “host IP” from the em0.8 interface to the bridge interface that’s including em0.8 then I can no longer communicate with that IP from the rest of the network.

In the output below I can ping 192.168.53.42  from another system on VLAN 53 (outside this box) and I can ping 192.168.53.42  from another system on the bridge, but I can’t ping between the system outside this box and the VM on the bridge.

I’ve disabled pf everywhere.

As I mentioned, some traffic crosses but it seems like arp requests gets blocked somewhere?

I don’t think it’s the switch, because as long as I don’t use the bridge everything works fine. :-/

Any suggestions?  (or other debug output that’d be useful).


Ask



root at helgi:~ # ifconfig em0
em0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=812099<RXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,VLAN_HWFILTER>
	ether c0:3f:d5:6d:77:87
	inet 192.168.4.42 netmask 0xfffffc00 broadcast 192.168.7.255
	inet6 fe80::c23f:d5ff:fe6d:7787%em0 prefixlen 64 scopeid 0x1
	inet6 2601:647:4400:2f50:c23f:d5ff:fe6d:7787 prefixlen 64 autoconf
	media: Ethernet autoselect (1000baseT <full-duplex>)
	status: active
	nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>
root at helgi:~ # ifconfig em0.53
em0.53: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=1<RXCSUM>
	ether c0:3f:d5:6d:77:87
	inet 192.168.53.42 netmask 0xffffff00 broadcast 192.168.53.255
	inet6 fe80::c23f:d5ff:fe6d:7787%em0.53 prefixlen 64 scopeid 0x4
	groups: vlan
	vlan: 53 vlanpcp: 0 parent interface: em0
	media: Ethernet autoselect (1000baseT <full-duplex>)
	status: active
	nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>
root at helgi:~ # ifconfig vm-dns
vm-dns: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether 66:28:db:a7:63:1b
	id 00:00:00:00:00:00 priority 32768 hellotime 2 fwddelay 15
	maxage 20 holdcnt 6 proto rstp maxaddr 2000 timeout 1200
	root id 00:00:00:00:00:00 priority 32768 ifcost 0 port 0
	member: tap2 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
	        ifmaxaddr 0 port 10 priority 128 path cost 2000000
	member: em0.53 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
	        ifmaxaddr 0 port 4 priority 128 path cost 55
	groups: bridge vm-switch viid-b3bf6@
	nd6 options=1<PERFORMNUD>


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