ERROR log "No DHCP agents are associated with network" is not an error in most cases

[Akihiro Motoki]

dhcp-agent notifier outputs ERROR log "No DHCP agents are associated with network"
but it is not an error and valid cases in most cases. It is so annoying for debugging and monitoring.

No dhcp-agent association for a network was logged as ERROR level. However it is completely incorrect for network_create_end, and usually wrong for subnet_create_end (because a subnet is created just after a network is created in most cases). We should not log it for these cases.

For other cases, a dhcp-agent is usually associated with a network, and no dhcp-agent assocation might be a symptom of some error. On the other hand there are valid cases where no dhcp-agent is associated (e.g., delete dhcp-agent association intentionally, network/subnet_update_end before a port is created). Considering these and the fact that error will be logged in
dhcp-agent scheduler, it would be better to be logged as INFO level now.

2014-03-07 02:29:08.533 5415 ERROR neutron.api.rpc.agentnotifiers.dhcp_rpc_agent_api [req-0babab8c-d638-4f1e-aef3-d58ad6af8b86 None] No DHCP agents are associated with network '6c3c60c7-2fce-4513-971c-b49b98d153c8'. Unable to send notification for 'network_create_end' with payload: {'network': {'status': 'ACTIVE', 'subnets': [], 'name': u'private', 'provider:physical_network': None, 'admin_state_up': True, 'tenant_id': u'33f39be0287d4316a29a4247dcd6db5c', 'provider:network_type': u'local', 'shared': False, 'id': '6c3c60c7-2fce-4513-971c-b49b98d153c8', 'provider:segmentation_id': None}}

http://logs.openstack.org/35/78835/1/check/check-tempest-dsvm-neutron/cd96f2f/logs/screen-q-svc.txt.gz?level=ERROR

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/78859

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/79458
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=fb9886b903434321e62373cb4c11ba014921e4df
Submitter: Jenkins
Branch: master

commit fb9886b903434321e62373cb4c11ba014921e4df
Author: armando-migliaccio <email address hidden>
Date: Mon Mar 10 14:29:29 2014 -0700

    Fix misleading error message about failed dhcp notifications

    This is achieved by adjusting the log traces and ensuring
    that the right log errors are emitted based on the status
    of the network.

    Also, the patch drastically simplifies the structure of the
    notification method and unit tests to increase coverage.

    Closes-bug: #1289130

    Change-Id: I7cc78bba81c516380fc93a68aa7b295312a88e29

[Timur Nurlygayanov (tnurlygayanov)]

Also reproduced on Openstack Havanna 2013.2.2

Do we plan to fix it for stable Havanna release?

[Armando Migliaccio (armando-migliaccio)]

I'll give a shot at cherry-picking it for havana...but the patch turned out to be fairly big so I am not sure it's is havana material.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/havana
Review: https://review.openstack.org/96712

[OpenStack Infra (hudson-openstack)]

Change abandoned by Armando Migliaccio (<email address hidden>) on branch: stable/havana
Review: https://review.openstack.org/96712

[Armando Migliaccio (armando-migliaccio)]

Timur, I tried the cherry-pick but the two branches look drastically different, as far as UT's are concerned. So, unless someone else wants to have at stub at it, this issue remains unsolved in Havana.