[Env]
OpenStack: icehouse
OS: ubuntu
enable l2 population
enable gre tunnel
[Description]
If the dhcp and l3 agent on the same host, then after this host is down, then there will be a probability that scheduled to other same host, then sometimes the ovs tunnel can't be created on the new scheduled host.
[Root cause]
After debugging, we found below log:
2015-01-14 13:44:18.284 9815 INFO neutron.plugins.ml2.drivers.l2pop.db [req-e36fe1fe-a08c-43c9-9d9c-75fe714d6f91 None] query:[<neutron.db.model
s_v2.Port[object at 7f8d706a3650] {tenant_id=u'ae27091dccf148249349d6396e10f230', id=u'2061f5e4-c4a0-42ae-b611-4fe6c2c5cfbd', name=u'', network
_id=u'12ee7040-119a-47bf-a968-67509ebb8eda', mac_address=u'fa:16:3e:b6:20:8e', admin_state_up=True, status=u'ACTIVE', device_id=u'dhcp28f6fc30-
af6e-5f44-ae85-dcc1cc074ee5-12ee7040-119a-47bf-a968-67509ebb8eda', device_owner=u'network:dhcp'}>, <neutron.db.models_v2.Port[object at 7f8d706
a37d0] {tenant_id=u'ae27091dccf148249349d6396e10f230', id=u'6e99eae8-5c6a-4b8e-b9e1-dbd8d133dfa1', name=u'', network_id=u'12ee7040-119a-47bf-a9
68-67509ebb8eda', mac_address=u'fa:16:3e:22:56:ba', admin_state_up=True, status=u'ACTIVE', device_id=u'e63a0802-d86d-4a30-95fa-0005a6aef6fb', d
evice_owner=u'network:router_interface'}>]
Above shows there will be a probability that two ACTIVE ports shows up in db together, but from l2 pop mech_driver:
"
if agent_active_ports == 1 or (
self.get_agent_uptime(agent) < cfg.CONF.l2pop.agent_boot_time):
"
only in above condition the fdb entry will be added and notified to agent, so failures are pop up.
---------------------------
[Impact]
This patch addresses an issue on neutron(1:2014.1.5-0ubuntu6) where no tunnel is created between network node and compute node during failover testing and which causing vms unreachable.
[Test Case]
Deploy an OpenStack cloud w/ trusty-icehouse with neutron HA, doing failover tests on network nodes, there will be a high certain rate that this issue happened.
[Regression Potential]
None.
I see the issue, when dhcp port is first created and then the router port created on the new host.
In this case, when dhcp port is first created, it has to create tunnel port also. But it is not doing that -
When a dhcp server is moved new host,
1) network-hostagent binding is updated(properly i.e with new host).
2) dhcp port-hostagent binding is not updated( dhcp port is still bound to old host)
If dhcp port-bound agent is different from the new dhcp agent(which is now taking care of this dhcp port), neutron plugin won't notify the l2pop, and hence tunnel is not created.
def update_
if (host and not plugin.
return
So, the root cause is - issue with dhcp and not l2pop(l2pop conditions are fine).