Hi all,
Thanks Terry.
As I'm using an old OVS (2.13)/OVN(20.3) version due openstack release (Ussuri), would it be possible to upgrade only the OVN/OVS without upgrading the whole openstack?
I'm only checking options in this case, how are you guys dealing with this in production?
Regards,
Tiago Pires
Sorry, I was on PTO. Jakub is right, w/o using python-ovs 2.17, when
ovs breaks the connection for the leadership clients will re-download
the entire content of their registered tables. With 2.17,
monitor-cond-since/update3 support is added to python-ovs and it
should just download the changes since they reconnected. As long as
the client code handles reconnections, this reconnecting should not be
an issue. It is still possible that there is code that doesn't
properly handle reconnections in general, but I'd start with trying
ovs 2.17. The disonnections will always happen, but they shouldn't
break things.
On Fri, May 6, 2022 at 5:13 PM Tiago Pires <tiagohp@gmail.com> wrote:
>
> Hi Mohammed,
>
> It seems a little bit like our issue.
>
> Thank you.
>
> Tiago Pires
>
> Em sex., 6 de mai. de 2022 às 18:21, Mohammed Naser <mnaser@vexxhost.com> escreveu:
>>
>> Hi Tiago,
>>
>> Have you seen this?
>>
>> https://bugs.launchpad.net/nova/+bug/1969592
>>
>> Mohammed
>>
>> On Fri, May 6, 2022 at 3:56 PM Tiago Pires <tiagohp@gmail.com> wrote:
>> >
>> > Hi all,
>> >
>> > I was checking the mail list history and this thread https://mail.openvswitch.org/pipermail/ovs-discuss/2018-March/046438.html caught my attention about raft ovsdb clustering.
>> > In my setup (OVN 20.03 and Openstack Ussuri) on the ovn-controller we have configured the ovn-remote="tcp:10.2X.4X.4:6642,tcp:10.2X.4X.68:6642,tcp:10.2X.4X.132:6642" with the 3 OVN central member that they are in cluster mode.
>> > Also on the neutron ML2 side:
>> > [ovn]
>> > ovn_native_dhcp = True
>> > ovn_nb_connection = tcp:10.2X.4X.4:6641,tcp:10.2X.4X.68:6641,tcp:10.2X.4X.132:6641
>> > ovn_sb_connection = tcp:10.2X.4X.4:6642,tcp:10.2X.4X.68:6642,tcp:10.2X.4X.132:6642
>> >
>> > We are experiencing an issue with Neutron when the OVN leader decide to take a snapshot and by design another member became leader(more less every 8 minutes):
>> > 2022-05-05T16:57:42.135Z|17401|raft|INFO|Transferring leadership to write a snapshot.
>> >
>> > ovs-appctl -t /var/run/ovn/ovnsb_db.ctl cluster/status OVN_Southbound
>> > 4a03
>> > Name: OVN_Southbound
>> > Cluster ID: ca74 (ca744caf-40cd-4751-a2f2-86e35ad6541c)
>> > Server ID: 4a03 (4a0328dc-e9a4-495e-a4f1-0a0340fc6d19)
>> > Address: tcp:10.2X.4X.132:6644
>> > Status: cluster member
>> > Role: leader
>> > Term: 1912
>> > Leader: self
>> > Vote: self
>> >
>> > Election timer: 10000
>> > Log: [497643, 498261]
>> > Entries not yet committed: 0
>> > Entries not yet applied: 0
>> > Connections: ->3d6c ->4ef0 <-3d6c <-4ef0
>> > Servers:
>> > 4a03 (4a03 at tcp:10.2X.4X.132:6644) (self) next_index=497874 match_index=498260
>> > 3d6c (3d6c at tcp:10.2X.4X.68:6644) next_index=498261 match_index=498260
>> > 4ef0 (4ef0 at tcp:10.2X.4X.4:6644) next_index=498261 match_index=498260
>> >
>> > As I understood the tcp connections from the Neutron (NB) and ovn-controllers (SB) to OVN Central are established only with the leader:
>> >
>> > #OVN central leader
>> > $ netstat -nap | grep 6642| more
>> >
>> > tcp 0 0 0.0.0.0:6642 0.0.0.0:* LISTEN -
>> > tcp 0 0 10.2X.4X.132:6642 10.24.40.17:47278 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.24.40.76:36240 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.17:47280 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.6:43102 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.75:58890 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.6:43108 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.17:47142 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.71:48808 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.132:6642 10.2X.4X.17:47096 ESTABLISHED -
>> > #OVN follower 2
>> >
>> > $ netstat -nap | grep 6642
>> >
>> > tcp 0 0 0.0.0.0:6642 0.0.0.0:* LISTEN -
>> > tcp 0 0 10.2X.4X.4:6642 10.2X.4X.76:57256 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.4:6642 10.2X.4X.134:54026 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.4:6642 10.2X.4X.10:34962 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.4:6642 10.2X.4X.6:49238 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.4:6642 10.2X.4X.135:59972 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.4:6642 10.2X.4X.75:40162 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.4:39566 10.2X.4X.132:6642 ESTABLISHED -
>> > #OVN follower 3
>> >
>> > netstat -nap | grep 6642
>> >
>> > tcp 0 0 0.0.0.0:6642 0.0.0.0:* LISTEN -
>> > tcp 0 0 10.2X.4X.68:6642 10.2X.4X.70:40750 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.68:6642 10.2X.4X.11:49718 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.68:45632 10.2X.4X.132:6642 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.68:6642 10.2X.4X.16:44816 ESTABLISHED -
>> > tcp 0 0 10.2X.4X.68:6642 10.2X.4X.7:45216 ESTABLISHED
>> >
>> > The issue that we are experiencing is on the neutron-server that disconnects when there is the ovn leader change (due snapshot like each 8 minutes) and reconnects to the next leader. It breaks the Openstack API when someone is trying to create a VM at the same time.
>> > First, is my current configuration correct? Should the leader change and break the neutron side? Or is there some missing configuration?
>> > I was wondering if it is possible to use a LB with VIP and this VIP balance the connections to the ovn central members and I would reconfigure on the neutron side only with the VIP and also on the ovs-controllers. Does that make sense?
>> >
>> > Thank you.
>> >
>> > Regards,
>> >
>> > Tiago Pires
>>
>>
>>
>> --
>> Mohammed Naser
>> VEXXHOST, Inc.