Bridge L2 behiavor abnormal

Bugs
1

There is a topo:

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[root@wluo 1-broadcast]$ clab inspect -a
+---+-----------+------------------+-------------------------------+--------------+------------------------------------+-------+---------+----------------+--------------+
| # | Topo Path |     Lab Name     |             Name              | Container ID |               Image                | Kind  |  State  |  IPv4 Address  | IPv6 Address |
+---+-----------+------------------+-------------------------------+--------------+------------------------------------+-------+---------+----------------+--------------+
| 1 | clab.yaml | broadcast-packet | clab-broadcast-packet-br1     | 71f76cc80ddd | 192.168.2.100:5000/vyos/vyos:1.4.7 | linux | running | 172.20.20.2/24 | N/A          |
| 2 |           |                  | clab-broadcast-packet-server1 | 82ece864497d | 192.168.2.100:5000/xcni            | linux | running | 172.20.20.4/24 | N/A          |
| 3 |           |                  | clab-broadcast-packet-server2 | 71f265e2b934 | 192.168.2.100:5000/xcni            | linux | running | 172.20.20.3/24 | N/A          |
+---+-----------+------------------+-------------------------------+--------------+------------------------------------+-------+---------+----------------+--------------+
[root@wluo 1-broadcast]$ 
clab-broadcast-packet-server1:
[root@wluo 1-broadcast]$ lo clab-broadcast-packet-server1 ip a 
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: tunl0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN group default qlen 1000
    link/ipip 0.0.0.0 brd 0.0.0.0
1177: eth0@if1178: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default 
    link/ether 02:42:ac:14:14:04 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 172.20.20.4/24 brd 172.20.20.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::42:acff:fe14:1404/64 scope link 
       valid_lft forever preferred_lft forever
1181: net0@if1182: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9500 qdisc noqueue state UP group default 
    link/ether aa:c1:ab:5d:69:46 brd ff:ff:ff:ff:ff:ff link-netnsid 1
    inet 10.1.5.10/24 scope global net0
       valid_lft forever preferred_lft forever
    inet6 fe80::a8c1:abff:fe5d:6946/64 scope link 
       valid_lft forever preferred_lft forever
1183: net1@if1184: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9500 qdisc noqueue state UP group default 
    link/ether aa:c1:ab:ca:38:1e brd ff:ff:ff:ff:ff:ff link-netnsid 1
    inet6 fe80::a8c1:abff:feca:381e/64 scope link 
       valid_lft forever preferred_lft forever
[root@wluo 1-broadcast]$ 

clab-broadcast-packet-server2
[root@wluo 1-broadcast]$ lo clab-broadcast-packet-server2 ip a 
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: tunl0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN group default qlen 1000
    link/ipip 0.0.0.0 brd 0.0.0.0
1175: eth0@if1176: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default 
    link/ether 02:42:ac:14:14:03 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 172.20.20.3/24 brd 172.20.20.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::42:acff:fe14:1403/64 scope link 
       valid_lft forever preferred_lft forever
1179: net0@if1180: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9500 qdisc noqueue state UP group default 
    link/ether aa:c1:ab:e4:13:b7 brd ff:ff:ff:ff:ff:ff link-netnsid 1
    inet 10.1.5.11/24 scope global net0
       valid_lft forever preferred_lft forever
    inet6 fe80::a8c1:abff:fee4:13b7/64 scope link 
       valid_lft forever preferred_lft forever
[root@wluo 1-broadcast]$ 

clab-broadcast-packet-br1:
[root@wluo 1-broadcast]$ cat startup-conf/gw1-boot.cfg 
interfaces {
    bridge br1 {
        address 10.1.5.1/24
        enable-vlan
        member {
            interface eth1 {
                native-vlan 5
            }
            interface eth2 {
                native-vlan 5
            }
            interface eth3 {
                native-vlan 5
            }
        }

when trigger a ping from server2 to server1. we can see the eth3 can get the arp broadcast and ICMP request packet:

root@br1:~# tcpdump -pne -i eth3
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on eth3, link-type EN10MB (Ethernet), snapshot length 262144 bytes
02:47:34.187189 aa:c1:ab:e4:13:b7 > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 10.1.5.10 tell 10.1.5.11, length 28
02:47:34.187223 aa:c1:ab:ca:38:1e > aa:c1:ab:e4:13:b7, ethertype ARP (0x0806), length 42: Reply 10.1.5.10 is-at aa:c1:ab:ca:38:1e, length 28
02:47:34.187253 aa:c1:ab:e4:13:b7 > aa:c1:ab:ca:38:1e, ethertype IPv4 (0x0800), length 98: 10.1.5.11 > 10.1.5.10: ICMP echo request, id 66, seq 1, length 64
02:47:35.205803 aa:c1:ab:e4:13:b7 > aa:c1:ab:ca:38:1e, ethertype IPv4 (0x0800), length 98: 10.1.5.11 > 10.1.5.10: ICMP echo request, id 66, seq 2, length 64
02:47:36.230446 aa:c1:ab:e4:13:b7 > aa:c1:ab:ca:38:1e, ethertype IPv4 (0x0800), length 98: 10.1.5.11 > 10.1.5.10: ICMP echo request, id 66, seq 3, length 64
02:47:37.253589 aa:c1:ab:e4:13:b7 > aa:c1:ab:ca:38:1e, ethertype IPv4 (0x0800), length 98: 10.1.5.11 > 10.1.5.10: ICMP echo request, id 66, seq 4, length 64
02:47:38.277622 aa:c1:ab:e4:13:b7 > aa:c1:ab:ca:38:1e, ethertype IPv4 (0x0800), length 98: 10.1.5.11 > 10.1.5.10: ICMP echo request, id 66, seq 5, length 64
^C
7 packets captured
7 packets received by filter
0 packets dropped by kernel
root@br1:~# ls
root@br1:~# exit

but after a while(the above test is shown that after 7 packets the ICMP is disappeared.)
in my view, the eth3 only can be capture the arp packet, rt? but for the case it seems there is a bug here.
would you pls double check the case and wait your feedback.

2

After:

vyos@br1# set interfaces ethernet eth3
[edit]
vyos@br1# commit
save
[edit]
vyos@br1# save
Saving configuration to '/config/config.boot'...
Done

the case is norml:

root@br1:/# tcpdump -pne -i eth3
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on eth3, link-type EN10MB (Ethernet), snapshot length 262144 bytes
03:05:06.015241 aa:c1:ab:5d:69:46 > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 10.1.5.11 tell 10.1.5.10, length 28
^C
1 packet captured
1 packet received by filter
0 packets dropped by kernel

but the question is that the function about “vyos@br1# set interfaces ethernet eth3” for waht?
in which situation that we must add this configuraton, and which not.

3

the interfaces should be present in our system , at least , this is used to create vlan-aware configuration , if you don’t need traffic with tag ,you can use regular bridge which works without the need to tagging the interfaces .

https://docs.vyos.io/en/latest/configuration/interfaces/bridge.html#create-a-basic-bridge

4

yes, the interface should be there.