allowed-address-pair between dvr east-west networks does not work at all

[LIU Yulong]

ENV: devstack with master branch neutron
HEAD: ab24a11f13cdfdf623a4b696f469aa621d59405b

Reproduce:
1. network1 + subnet1: 192.168.1.0/24
2. network2 + subnet2: 192.168.2.0/24
3. dvr router with attached subnets: subnet1, subnet2
4. VM1 (192.168.1.10) and VM2 (192.168.1.11) created from network1, VM3 (192.168.2.20) from network2
5. create a port from network1 and its fixed-IP-1 (192.168.1.100) will be used as VIP
6. set VM1 & VM2 port allowed-address-pair: openstack port set --allowed-address ip-address=192.168.1.100 VM1-port/VM2-port
7. set the VIP to the NIC inside the VM1 or VM2
8. try to access/ping VIP fixed-IP-1 (192.168.1.100) from VM3

Excepted behavior:
pingable, 192.168.2.20 can reach 192.168.1.100

Actual behavior: not reachable

[James Denton (james-denton)]

We are waiting on https://review.opendev.org/#/c/601336/ to resolve a similar issue. Not sure if it's completely related, but definitely affecting the use of allowed address pairs w/ DVR for us.

[LIU Yulong (dragon889)]

Sorry, I forget the bug 1774459....

[LIU Yulong (dragon889)]

Patch https://review.opendev.org/#/c/601336/ seems not handle the VIP traffic cross dvr east-west network.

Removed the duplicated mark.