OVS agent not reconfigure ext-bridge in case when it was removed and created again by administrator

[Slawek Kaplonski]

Neutron OVS agent will configure phys_bridges only during agent start process.
If later someone remove and create such bridge again it will clean all flows from it.
Because such bridges are configured with "fail_mode=secure" that might cause to lost of connection in Neutron control plane as it is quite common deployment practice to use same external bridge for data plane and for control plane.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/566178

[Andreas Karis (akaris)]

I'd like to add to the issue description that I don't thinkg that the fail_mode is necessarily the culprit. But if somebody or something (e.g. tripleo) deletes and recreates the bridge, the bridge will lose all settings, such as:
* flows
* virtual patch cable into br-int
* fail_mode settings

[Slawek Kaplonski (slaweq)]

@Andreas. Bridge with fail_mode="secure" will not set up flows on its own when the controller connection fails and without any flow rules for bridge packets will be dropped. That will cause problems with control plane connections if control plane also uses such external bridge.
Problem here is that "fail_mode" is stored in ovsdb so it is persistent but open flow rules are not persistent.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/566178
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=85b46cd51ebec67d5018d8bef4f796ee5ef4fedf
Submitter: Zuul
Branch: master

commit 85b46cd51ebec67d5018d8bef4f796ee5ef4fedf
Author: Sławek Kapłoński <email address hidden>
Date: Fri May 4 00:12:03 2018 +0200

    Monitor phys_bridges to reconfigured it if created again

    In case when external bridge configured in OVS agent's bridge_mappings
    will be destroyed and created again (for example by running ifup-ovs
    script on Centos) bridge wasn't configured by OVS agent.
    That might cause broken connectivity for OpenStack's dataplane if
    dataplane network also uses same bridge.

    This patch adds additional ovsdb-monitor to monitor if any
    of physical bridges configured in bridge_mappings was created.
    If so, agent will reconfigure it to restore proper openflow rules
    on it.

    Change-Id: I9c0dc587e70327e03be5a64522d0c679665f79bd
    Closes-Bug: #1768990

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/queens
Review: https://review.openstack.org/567145

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/pike
Review: https://review.openstack.org/567691

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/567145
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=62240c10971274c03632ee25b92848f0f138b28e
Submitter: Zuul
Branch: stable/queens

commit 62240c10971274c03632ee25b92848f0f138b28e
Author: Sławek Kapłoński <email address hidden>
Date: Fri May 4 00:12:03 2018 +0200

    Monitor phys_bridges to reconfigured it if created again

    In case when external bridge configured in OVS agent's bridge_mappings
    will be destroyed and created again (for example by running ifup-ovs
    script on Centos) bridge wasn't configured by OVS agent.
    That might cause broken connectivity for OpenStack's dataplane if
    dataplane network also uses same bridge.

    This patch adds additional ovsdb-monitor to monitor if any
    of physical bridges configured in bridge_mappings was created.
    If so, agent will reconfigure it to restore proper openflow rules
    on it.

    Change-Id: I9c0dc587e70327e03be5a64522d0c679665f79bd
    Closes-Bug: #1768990
    (cherry picked from commit 85b46cd51ebec67d5018d8bef4f796ee5ef4fedf)

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/567691
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=b557d4ac6cd51fc3e3bd424b14fb32013a41c557
Submitter: Zuul
Branch: stable/pike

commit b557d4ac6cd51fc3e3bd424b14fb32013a41c557
Author: Sławek Kapłoński <email address hidden>
Date: Fri May 4 00:12:03 2018 +0200

    Monitor phys_bridges to reconfigured it if created again

    In case when external bridge configured in OVS agent's bridge_mappings
    will be destroyed and created again (for example by running ifup-ovs
    script on Centos) bridge wasn't configured by OVS agent.
    That might cause broken connectivity for OpenStack's dataplane if
    dataplane network also uses same bridge.

    This patch adds additional ovsdb-monitor to monitor if any
    of physical bridges configured in bridge_mappings was created.
    If so, agent will reconfigure it to restore proper openflow rules
    on it.

    Change-Id: I9c0dc587e70327e03be5a64522d0c679665f79bd
    Closes-Bug: #1768990
    (cherry picked from commit 85b46cd51ebec67d5018d8bef4f796ee5ef4fedf)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 13.0.0.0b2 development milestone.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 12.0.3 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 11.0.5 release.