Merge "Adds availability zones to nova datasource driver"

2015-12-03 02:12:31 +00:00 · 2015-12-03 02:12:31 +00:00 · 5fa83b1306
parent 3e8cccc0a3 56e879ea2c
commit 5fa83b1306
1 changed files with 152 additions and 0 deletions
--- a/specs/mitaka/add-az-to-nova-driver.rst
+++ b/specs/mitaka/add-az-to-nova-driver.rst
@ -0,0 +1,152 @@
+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+===============================================================
+Add availability zones to nova datasource driver
+===============================================================
+
+https://blueprints.launchpad.net/congress/+spec/add-az-to-nova-driver
+
+This specification presents to extend the current nova datasource driver for
+supporting availability zone and its fields available from nova.
+
+Problem description
+===================
+
+The current nova provides avaiability zones for server and host. A host is a
+part of availability zone and server can be booted on the availability zone.
+However, the current nova datasource driver does not support it.
+This availability zone are useful for creating any policy related to server
+location.
+For example, we can specify a policy for checking status of any VMs located in
+the specific availability zone. In addition, we can specify an action policy
+for migrating some VMs from availability zone A to availability zone B.
+
+Recently, availability zone was added to servers using
+OS-EXT-AZ:availability_zone [1].
+However, it is hard to make full hierarchy among availability zone, hosts, and
+servers and lack of flexiblity and extensibility. If we add the availability
+zone to nova data source driver, it will be more flexible and extensible to use
+more fields available from the availability zone such as zone state.
+
+Proposed change
+===============
+
+Basically, we can extend the curret Nova datasource driver
+(datasources/nova_driver.py) by adding the following a translator and
+two fields.
+
+* availabilty_zones_translator
+
+  * zone_name
+  * zone_state
+
+
+Alternatives
+------------
+
+N/A
+
+
+Policy
+------
+
+Using the Congress datalog syntax, write out an example policy using
+https://wiki.openstack.org/wiki/Congress#Policy_Language
+
+Example:
+
+host_availability_zone(vm,zone_name) :-
+    nova:hosts(host_name,zone=zone_name),
+    nova:availability_zones(zone_name=zone_name)
+
+
+Policy actions
+--------------
+
+
+Data sources
+------------
+
+nova
+
+
+Data model impact
+-----------------
+
+N/A
+
+REST API impact
+---------------
+
+N/A
+
+Security impact
+---------------
+
+N/A
+
+Notifications impact
+--------------------
+
+N/A
+
+Other end user impact
+---------------------
+
+N/A
+
+Performance impact
+------------------
+
+N/A
+
+Other deployer impact
+---------------------
+
+N/A
+
+Developer impact
+----------------
+
+N/A
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  Joon Kang <joon-myung-kang>
+
+Work items
+----------
+
+* Implement availability_zone_translator in nova datasource driver
+* Perform unit testing
+* Perform functional testing for the new field
+
+
+Dependencies
+============
+
+N/A
+
+Testing
+=======
+
+* Test host and availability zones using the policy
+
+Documentation impact
+====================
+
+TBD
+
+References
+==========
+[1] /congress/commit/9f9e26f850d12c73721b5e6b45ac00997c8c24c2
+[2] http://docs.openstack.org/openstack-ops/content/scaling.html