Cannot set the VXLAN UDP destination port to 4789 using Linux Bridge

[Danny Choi]

I'm running stable/Juno with VXLAN and Linux Bridge.

Linux default VxLAN UDP port is 8472.

IANA assigned port is 4789.

I tried to add the following in /etc/neutron/plugins/ml2/ml2_conf.ini file, but it still use port 8472 afterwards.

[agent]
vxlan_udp_port=4789

##############################################

Comments from Kevin Benton:

Looking at the code, it doesn't look like vxlan_udp_port applies to Linux Bridge. Please file a bug and we should be able to get a fix pretty quickly.

[yuntongjin (yuntongjin)]

assume you are using Ml2 driver,
yet there is no vxlan_udp_port option in ml2_conf.ini.
need support this option in ml2 driver.

[yuntongjin (yuntongjin)]

now i figure out that ovs agent will load conf from ml2_conf.ini.

[yuntongjin (yuntongjin)]

man ip-link:
port MIN MAX - specifies the range of port numbers to use as UDP source ports to communicate to the remote VXLAN tunnel endpoint.

looks like vxlan on linux-bridge doesn't support specifies port number. only support specifies the range of port numbers

[Kevin Benton (kevinbenton)]

the required modification will be in the bridge fbd add calls.

[Kevin Benton (kevinbenton)]

fdb*

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/215422

[OpenStack Infra (hudson-openstack)]

Change abandoned by Armando Migliaccio (<email address hidden>) on branch: master
Review: https://review.openstack.org/215422
Reason: This review is > 4 weeks without comment, and failed Jenkins the last time it was checked. We are abandoning this for now. Feel free to reactivate the review by pressing the restore button and leaving a 'recheck' comment to get fresh test results.

[Armando Migliaccio (armando-migliaccio)]

Juno is EOL, can you confirm this happens in master/newer releases too?

[Tore Anderson (toreanderson)]

Still relevant as of Mitaka. A workaround is to create the file /etc/modprobe.d/vxlan.conf containing "options vxlan udp_port=4789".

[Steve Ruan (ruansx)]

Hi Armando,

Test with the latest neutron code, Linux bridge still uses udp port 8472 as default port.
Here is use case for this bug:
When using vxlan to connect a OpenStack network to a hardware switch which can ONLY support the default udp port 4789. But Linux bridge use 8472 as destination and source udp port. It can NOT work.

If the reporter is not available, please assign to me.

[Launchpad Janitor (janitor)]

[Expired for neutron because there has been no activity for 60 days.]

[Armando Migliaccio (armando-migliaccio)]

This bug is > 180 days without activity. We are unsetting assignee and milestone and setting status to Incomplete in order to allow its expiry in 60 days.

If the bug is still valid, then update the bug status.

[György Szombathelyi (gyurco)]

Seems in neutron/agent/linux/ip_lib.py, function add_vxlan misses the dstport parameter. However it has the port parameter with two arguments, what is it good for? Otherwise, it is an easy fix.

[György Szombathelyi (gyurco)]

So to answer myself, the port with the two arguments is the source port range, but it is also not set anywhere, so useless.

[György Szombathelyi (gyurco)]

https://git.kernel.org/pub/scm/linux/kernel/git/shemminger/iproute2.git/commit/?id=514cdfb443b1ab7911d7603f698121d805367260

Also it should be 'srcport' for 3 years now (and from Linux 3.12).

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/468911

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/468911
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=d7c4428525dac6cbde005f51bcd44b12ebc3bc0a
Submitter: Jenkins
Branch: master

commit d7c4428525dac6cbde005f51bcd44b12ebc3bc0a
Author: Gyorgy Szombathelyi <email address hidden>
Date: Mon May 29 16:21:15 2017 +0200

    Allow to set UDP ports for VXLAN in Linuxbridge agent

    Introduce vxlan.{udp_srcport_min, udp_srcport_max and udp_dstport}
    for setting the port range used for VXLAN communication.

    Change-Id: I97999988090eee7aee9b533ac1dad2de95b29cbe
    Closes-Bug: #1483853
    DocImpact: vxlan.{udp_srcport_min, udp_srcport_max and udp_dstport}
    can be used to set UDP port numbers used for VXLAN in LinuxBridge
    agent.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 11.0.0.0b3 development milestone.