GARP request from Fabric interface is not getting flooded to VM's

[Senthilnathan Murugappan]

Setup:
AAP associated to two VMs which runs keepalived with garp
The VMs are distributed across two computes.
Agent listens to vrrp mcast and adjusts the local preference accordingly however the garp request to update the arp table of the other vms in the network is lost. Looks like the garp broadcast pkts gets dual encapsulated (vxlan over mplsogre)
The preferred encap mode is set to mplsogre.

Hi Praveen, Anand,

Got a chance to try the same (garp on aap) and it looks like we encap it twice (vxlan over mplsogre).

GARP is sent for 77.7.7.6 from 02:ad:a8:06:1c:ce on compute host 5.5.5.16 to compute host 5.5.5.15

00:24:09.602302 IP (tos 0x0, ttl 64, id 47912, offset 0, flags [none], proto GRE (47), length 110)
    5.5.5.16 > 5.5.5.15: GREv0, Flags [none], length 90
        MPLS (label 4103, exp 0, [S], ttl 64)

mplsogre(5.5.5.16 - 5.5.5.15):
        0x0000: 4500 006e bb28 0000 402f ab10 0505 0510
        0x0010: 0505 050f 0000 8847 0100 7140 0000 0000

vxlan:
        0x0020: 4500 004e bb27 0000 4011 ab4e 0505 0510
        0x0030: 0505 0510 c2cd 12b5 003a 0000 0800 0000

garp:
        0x0040: 0000 0700 ffff ffff ffff 02ad a806 1cce
        0x0050: 0806 0001 0800 0604 0001 02ad a806 1cce
        0x0060: 4d07 0706 ffff ffff ffff 4d07 0706

In case if you wanna take a look at the setup.

Mgmt IP: 10.102.42.67 - 5.5.5.15
         10.102.42.68 - 5.5.5.16

Metadata IP: vrrp master: 169.254.0.6 on 5.5.5.16

- Senthil

From: Senthilnathan Murugappan
Sent: Thursday, July 23, 2015 11:22 AM
To: Praveen K V
Subject: RE: Contrail and GARP

Hi Praveen,

I tried vrrp+garp with aap a while back and had observed that garp is consumed by vrouter and never sent to all hosts in the VN.
Hope its not expected, will check the same again and update you.

- Senthil

[Senthilnathan Murugappan (msenthil)]

gcore of the agent is at /cs-shared/bugs/1478662/

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/12774
Submitter: Divakar Dharanalakota (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/12803
Submitter: Divakar Dharanalakota (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/12774
Committed: http://github.org/Juniper/contrail-vrouter/commit/163b8c0213c133f6ba43ce8ef2456ff3fdbf5fd2
Submitter: Zuul
Branch: R2.20

commit 163b8c0213c133f6ba43ce8ef2456ff3fdbf5fd2
Author: Divakar <email address hidden>
Date: Fri Jul 31 19:45:06 2015 +0530

Flooding Garp packet from fabric interface

In the allowed address pair scenario, to trap the Garp packets from VM,
the route is marked with T flag. But if the Gratuitous packet is from
fabric interface the packet needs to be given to VM's rather getting
trapped to Agent. Right now for all Garp packets, the route flag is
considered and if T is set, it is trapped to agent. This is leading to
Garp not getting flooded to VM's.

As a fix, Garp packets from fabric are always flooded.

Change-Id: I3731ae74df92c03edc0c95502d5984455992179c
closes-bug: #1478662

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/12803
Committed: http://github.org/Juniper/contrail-vrouter/commit/123412f2d59e97241357cec6ea6474b9fe023b1a
Submitter: Zuul
Branch: master

commit 123412f2d59e97241357cec6ea6474b9fe023b1a
Author: Divakar <email address hidden>
Date: Mon Aug 3 11:04:11 2015 +0530

Flooding Garp packet from fabric interface

In the allowed address pair scenario, to trap the Garp packets from VM,
the route is marked with T flag. But if the Gratuitous packet is from
fabric interface the packet needs to be given to VM's rather getting
trapped to Agent. Right now for all Garp packets, the route flag is
considered and if T is set, it is trapped to agent. This is leading to
Garp not getting flooded to VM's.

As a fix, Garp packets from fabric are always flooded.

closes-bug: #1478662
Change-Id: I3731ae74df92c03edc0c95502d5984455992179c