3.1.1-B32: Retain flood flag in case of ECMP NH for subnet route

[Sandeep Sridhar]

Contrail - 3.1.1 - Build 32

Manish is aware of this issue.

We have noticed that with dual MX, VM is not able to resolve ARP for BMS. This causes the communication between BMS to VM.

BMS's MAC table had the MAC address of Virtual Machine. The packets from BMS was successfully reaching the tap of VM. However, the return traffic was not going through.

Dual MX:
root@contrail6:~# rt --dump 1 --family inet | grep 192.168.168.0
192.168.168.0/32 24 PT - 27 -

Single MX:
root@contrail6:~# rt --dump 1 --family inet | grep 192.168.168.0
192.168.168.0/32 24 LTF 16 22 -

Reason: The agent introspect did not have the BMS IP. In the absence of IP, we look at the subnet route. In case of dual MX, subnet route is sent by both MX. This causes NH to be ECMP. The moment we see ECMP NH, we do a L3 routing and we don't flood the packet. We proxy it with vRouter MAC.

Please retain the "F" flag even with ECMP next-hop.

Greetings,
Sandeep.

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/25097
Submitter: Manish Singh (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/25098
Submitter: Manish Singh (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/25098
Committed: http://github.org/Juniper/contrail-controller/commit/55eef66e5e9e781ad0371840d525f672cac835f5
Submitter: Zuul
Branch: R3.1

commit 55eef66e5e9e781ad0371840d525f672cac835f5
Author: Manish Singh <email address hidden>
Date: Thu Oct 20 12:39:35 2016 +0530

Restore flood flag on subnet route with ecmp nh.

If subnet route is pointing to subnet NH then all unknown IP(like BMS) will use
the same and arp for them from VM will result in proxy with vrrp mac and they
will be l3-routed.
To keep l2 behavior intact in same subnet flood all arp in subnet(defined by IPAM).

Change-Id: I7b109aa0081fd7c5cae985df5d88249d1285e938
Closes-bug: #1625939

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/25097
Committed: http://github.org/Juniper/contrail-controller/commit/a4b7bb2972afb9f50280a4d1afc3774819987400
Submitter: Zuul
Branch: master

commit a4b7bb2972afb9f50280a4d1afc3774819987400
Author: Manish Singh <email address hidden>
Date: Thu Oct 20 12:39:35 2016 +0530

Restore flood flag on subnet route with ecmp nh.

If subnet route is pointing to subnet NH then all unknown IP(like BMS) will use
the same and arp for them from VM will result in proxy with vrrp mac and they
will be l3-routed.
To keep l2 behavior intact in same subnet flood all arp in subnet(defined by IPAM).

Change-Id: I7b109aa0081fd7c5cae985df5d88249d1285e938
Closes-bug: #1625939

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/25266
Submitter: Manish Singh (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/25266
Committed: http://github.org/Juniper/contrail-controller/commit/555519262540255d78848a6f830b031110580e3a
Submitter: Zuul
Branch: R3.2

commit 555519262540255d78848a6f830b031110580e3a
Author: Manish Singh <email address hidden>
Date: Thu Oct 20 12:39:35 2016 +0530

Restore flood flag on subnet route with ecmp nh.

If subnet route is pointing to subnet NH then all unknown IP(like BMS) will use
the same and arp for them from VM will result in proxy with vrrp mac and they
will be l3-routed.
To keep l2 behavior intact in same subnet flood all arp in subnet(defined by IPAM).

Change-Id: I7b109aa0081fd7c5cae985df5d88249d1285e938
Closes-bug: #1625939