[5.1 contrail-command]adding routing policy with external community removing all the existing communites from the routes

[aswani kumar]

5.1 build 418 contrail-command

From contrail-command attaching routing policy with external_community attribute removing all the existing communities
from the routes

I tried same using vnc_api and not seeing this issue

Below one is my observation

without routing policy attached to virtual network I have following communities values with the routes

communities
target:64512:8000002
encapsulation:gre
encapsulation:udp
encapsulation:native
mobility:non-sticky:1
secgroup:64512:8000002
originvn:64512:4
tag:64512:65537
tag:64512:131074

Created the Routing policy with add_external_community target:64512:2000 and attached to virtual network

communities
target:64512:2000
target:64512:8000002
originvn:64512:4