Nova doesn't refresh network cache when transferring a floating IP address

[Phil Day]

When Nova associates of disassociates a floating IP address the network info cache is always refreshed (In both Nova net and Quantum) due to the @refresh_cache decorator

However if you (re)associate a floating IP which is already associated with another instance on a Quantum based system then the address is correcly disassociated first, but the refresh is not trigged for that instance. As a result Nova will show the same address for two instances until the periodic clean-up kicks in some minutes later.

Watch what happens with 15.184.41.5 in the following:

$nova list
+--------------------------------------+------------+--------+----------------------------------+
| ID | Name | Status | Networks |
+--------------------------------------+------------+--------+----------------------------------+
| 52e0533a-0399-4828-b9d7-f223c7e44aca | phil-natty | ACTIVE | philnet1=12.0.0.4, 15.184.41.5 |
| 8184e9a7-3f56-46bc-8a3a-4fba68f7ce78 | phil2 | ACTIVE | philnet1=12.0.0.3, 15.184.40.176 |
| 7ab2dff2-6a71-497a-b097-627833ebe680 | phil44 | ACTIVE | philnet1=12.0.0.5 |
+--------------------------------------+------------+--------+----------------------------------+

$quantum floatingip-list
+--------------------------------------+------------------+---------------------+--------------------------------------+
| id | fixed_ip_address | floating_ip_address | port_id |
+--------------------------------------+------------------+---------------------+--------------------------------------+
| 29d844c4-78f8-45fd-ae28-d518ea6d41ef | 12.0.0.4 | 15.184.41.5 | 4770c516-6b07-44c2-a07b-eb13a873f80e |
| 9f0f7dfe-4e2f-4a60-8cfd-c7b8c7a10ea9 | 12.0.0.3 | 15.184.40.176 | 58cc4d39-7c20-4a36-bf5f-267a193f6f44 |
+--------------------------------------+------------------+---------------------+--------------------------------------+

$nova add-floating-ip 7ab2dff2-6a71-497a-b097-627833ebe680 15.184.41.5

$quantum floatingip-list
+--------------------------------------+------------------+---------------------+--------------------------------------+
| id | fixed_ip_address | floating_ip_address | port_id |
+--------------------------------------+------------------+---------------------+--------------------------------------+
| 29d844c4-78f8-45fd-ae28-d518ea6d41ef | 12.0.0.5 | 15.184.41.5 | 3470b721-def6-48a9-8b19-16bd564dd795 |
| 9f0f7dfe-4e2f-4a60-8cfd-c7b8c7a10ea9 | 12.0.0.3 | 15.184.40.176 | 58cc4d39-7c20-4a36-bf5f-267a193f6f44 |
+--------------------------------------+------------------+---------------------+--------------------------------------+

$nova list
+--------------------------------------+------------+--------+----------------------------------+
| ID | Name | Status | Networks |
+--------------------------------------+------------+--------+----------------------------------+
| 52e0533a-0399-4828-b9d7-f223c7e44aca | phil-natty | ACTIVE | philnet1=12.0.0.4, 15.184.41.5 |
| 8184e9a7-3f56-46bc-8a3a-4fba68f7ce78 | phil2 | ACTIVE | philnet1=12.0.0.3, 15.184.40.176 |
| 7ab2dff2-6a71-497a-b097-627833ebe680 | phil44 | ACTIVE | philnet1=12.0.0.5, 15.184.41.5 |
+--------------------------------------+------------+--------+----------------------------------+

Nova Networking has specific handling for this case in its associate_floating_ip() method, which relies on the floating_manager returning the instance uuid of the original instance. It doesn't look like the quantum client does this, so the quantumv2/api code will probably need to work this out for itself.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/33054

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/33054
Committed: http://github.com/openstack/nova/commit/49fdad5b6d1e0878438571c2e9c0421bc522cb2e
Submitter: Jenkins
Branch: master

commit 49fdad5b6d1e0878438571c2e9c0421bc522cb2e
Author: Phil Day <email address hidden>
Date: Fri Jun 14 14:26:51 2013 +0100

    Refresh network cache when reassigning a floating IP in Neutron

    When Nova associates or disassociates a floating IP address
    the network info cache is always refreshed due to the
    @refresh_cache decorator

    However if you (re)associate a floating IP which is already
    associated with another instance on a Neutron based system then
    the address is correcly disassociated first, but the cache refresh
    is not trigged for the original instance. As a result Nova will
    show the same address for two instances until the periodic
    clean-up kicks in some minutes later.

    Fixed bug: 1173227

    Change-Id: Iea81532911478026b9b2c0578a1eda7a97b09d80