Router may be removed from dvr_snat agent by accident

[Oleg Bondarev]

This popped up during https://review.openstack.org/#/c/238478
 - when dvr serviceable port is deleted/migrated, dvr callback checks if there are any more dvr serviceable ports on the host and if there are no - removes the router from the agent on that host
 - in case dhcp port is deleted/migrated this may lead to router being deleted from dvr_snat agent, which includes snat namespace deletion

Need to check agent mode and only remove router from dvr agents running on compute nodes in this case.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/255989

[Swaminathan Vasudevan (swaminathan-vasudevan)]

Category Low.

[Carl Baldwin (carl-baldwin)]

Another problem that wouldn't have happened if we didn't explicitly bind routers to compute hosts.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/255989
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=521e1c9face737a8d432be16ad63829aaf21384e
Submitter: Jenkins
Branch: master

commit 521e1c9face737a8d432be16ad63829aaf21384e
Author: Oleg Bondarev <email address hidden>
Date: Thu Dec 10 19:49:25 2015 +0300

    Do not remove router from dvr_snat agents on dvr port deletion

    When dvr serviceable port is deleted/migrated, dvr callback checks
    if there are any more dvr serviceable ports on the host and if
    there are no - removes the router from the agent on that host.
    To prevent snat namespace removal we need to check SNAT bindings
    and not remove router from l3 agent hosting SNAT.

    Closes-Bug: #1524908
    Change-Id: I8c76bccdf495702e4c550df2eadec93c63e32120

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/neutron 8.0.0.0b3 development milestone.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/liberty
Review: https://review.openstack.org/293777

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/293777
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=3a22335834456d04e6f0b7fb296cb38a3eb4affb
Submitter: Jenkins
Branch: stable/liberty

commit 3a22335834456d04e6f0b7fb296cb38a3eb4affb
Author: Oleg Bondarev <email address hidden>
Date: Thu Dec 10 19:49:25 2015 +0300

    Do not remove router from dvr_snat agents on dvr port deletion

    When dvr serviceable port is deleted/migrated, dvr callback checks
    if there are any more dvr serviceable ports on the host and if
    there are no - removes the router from the agent on that host.
    To prevent snat namespace removal we need to check SNAT bindings
    and not remove router from l3 agent hosting SNAT.

    testcase test_dvr_deletens_if_no_ports_no_removeable_routers
    was removed because this change renders it invalid.

    See patch https://review.openstack.org/#/c/296851/

    Closes-Bug: #1524908
    Change-Id: I8c76bccdf495702e4c550df2eadec93c63e32120
    (cherry picked from commit 521e1c9face737a8d432be16ad63829aaf21384e)

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/neutron 7.1.0 release.