ovn-bgp-agent

Bug #2017889
Comment #16

Comment 16 for bug 2017889

Revision history for this message

Luis Tomas Bolivar (ltomasbo) wrote on 2023-05-23:

#16

Another interesting side effect, if you add on the host an ndp proxy:
$ ip nei show proxy
2001:db8:: dev br-ex proxy

The first ping fails:
[root@vm-provider ~]# ping f00d:f00d:f00d:4:5054:ff:fea5:f6e8 -c1
PING f00d:f00d:f00d:4:5054:ff:fea5:f6e8(f00d:f00d:f00d:4:5054:ff:fea5:f6e8) 56 data bytes
From 2001:db8::f816:3eff:fe9c:17b7 icmp_seq=1 Destination unreachable: Address unreachable
--- f00d:f00d:f00d:4:5054:ff:fea5:f6e8 ping statistics ---
1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms

[root@vm-provider ~]# ip nei
fe80::2c21:43ff:fe1e:244e dev eth0 lladdr 2e:21:43:1e:24:4e router REACHABLE
fe80::f816:3eff:fe3c:b5f8 dev eth0 FAILED

But the second succeeds:
[root@vm-provider ~]# ping f00d:f00d:f00d:4:5054:ff:fea5:f6e8 -c1
PING f00d:f00d:f00d:4:5054:ff:fea5:f6e8(f00d:f00d:f00d:4:5054:ff:fea5:f6e8) 56 data bytes
64 bytes from f00d:f00d:f00d:4:5054:ff:fea5:f6e8: icmp_seq=1 ttl=60 time=2.04 ms
--- f00d:f00d:f00d:4:5054:ff:fea5:f6e8 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 2.040/2.040/2.040/0.000 ms

[root@vm-provider ~]# ip nei
fe80::2c21:43ff:fe1e:244e dev eth0 lladdr 2e:21:43:1e:24:4e router REACHABLE
fe80::f816:3eff:fe3c:b5f8 dev eth0 FAILED
2001:db8:: dev eth0 lladdr 2e:21:43:1e:24:4e REACHABLE

Another interesting side effect, if you add on the host an ndp proxy:
$ ip nei show proxy
2001:db8:: dev br-ex proxy

[root@vm-provider ~]# ip nei
fe80::2c21:43ff:fe1e:244e dev eth0 lladdr 2e:21:43:1e:24:4e router REACHABLE
fe80::f816:3eff:fe3c:b5f8 dev eth0 FAILED

With tcpdump on the host:
06:04:09.469191 tapbae685a6-66 M   IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:09.469358 tap775d5de2-70 Out IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:09.469368 br-ex In  IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                                  
06:04:10.503886 tapbae685a6-66 M   IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:10.503896 tap775d5de2-70 Out IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:10.503910 br-ex In  IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                                  
06:04:11.527757 tapbae685a6-66 M   IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:11.527769 tap775d5de2-70 Out IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:11.527786 br-ex In  IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32

With  tcpdump on the host:
06:04:09.469191 tapbae685a6-66 M   IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:09.469358 tap775d5de2-70 Out IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:09.469368 br-ex In  IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                                  
06:04:10.503886 tapbae685a6-66 M   IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:10.503896 tap775d5de2-70 Out IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:10.503910 br-ex In  IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                                  
06:04:11.527757 tapbae685a6-66 M   IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:11.527769 tap775d5de2-70 Out IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32                                                                                         
06:04:11.527786 br-ex In  IP6 2001:db8::f816:3eff:fe9c:17b7 > ff02::1:ff3c:b5f8: ICMP6, neighbor solicitation, who has fe80::f816:3eff:fe3c:b5f8, length 32