charm should error on invalid min/max_l3_agents config

[Edward Hope-Morley]

If I set min-l3-agents-per-router > max-l3-agents-per-router the charm happily continues but neutron itself fails with:

...
2017-04-03 10:08:52.152 15766 ERROR neutron File "/usr/lib/python2.7/dist-packages/neutron/services/l3_router/l3_router_plugin.py", line 65, in __init__
2017-04-03 10:08:52.152 15766 ERROR neutron super(L3RouterPlugin, self).__init__()
2017-04-03 10:08:52.152 15766 ERROR neutron File "/usr/lib/python2.7/dist-packages/neutron/db/l3_hamode_db.py", line 184, in __init__
2017-04-03 10:08:52.152 15766 ERROR neutron self._verify_configuration()
2017-04-03 10:08:52.152 15766 ERROR neutron File "/usr/lib/python2.7/dist-packages/neutron/db/l3_hamode_db.py", line 169, in _verify_configuration
2017-04-03 10:08:52.152 15766 ERROR neutron self._check_num_agents_per_router()
2017-04-03 10:08:52.152 15766 ERROR neutron File "/usr/lib/python2.7/dist-packages/neutron/db/l3_hamode_db.py", line 178, in _check_num_agents_per_router
2017-04-03 10:08:52.152 15766 ERROR neutron max_agents=max_agents, min_agents=min_agents)
2017-04-03 10:08:52.152 15766 ERROR neutron HAMaximumAgentsNumberNotValid: max_l3_agents_per_router 2 config parameter is not valid. It has to be greater than or equal to min_l3_agents_per_router 3.

A simple check in the charm would avoid this.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/452710

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/452710
Committed: https://git.openstack.org/cgit/openstack/charm-neutron-api/commit/?id=a741d105bc9e2bd37223372e4b611a26a31de0bb
Submitter: Jenkins
Branch: master

commit a741d105bc9e2bd37223372e4b611a26a31de0bb
Author: Edward Hope-Morley <email address hidden>
Date: Mon Apr 3 12:01:45 2017 +0100

    Add validation of *-l3-agents-per-router config

    Change-Id: If426505b4a14115df3b918021aabf3ddef96c2c8
    Closes-Bug: 1679008