By default the L3 agent makes use of Linux network namespaces in order to support overlapping IP addresses. Requirements for network namespaces support are described in the Limitation section.
If the Linux installation does not support network namespace, you must disable using network namespace in the L3 agent config file (The default value of use_namespaces is True).
use_namespaces = False
When use_namespaces is set to False, only one router ID can be supported per node. This must be configured via the configuration variable router_id.
# If use_namespaces is set to False then the agent can only configure one router. # This is done by setting the specific router_id. router_id = 1064ad16-36b7-4c2f-86f0-daa2bcbd6b2a
To configure it, you need to run the OpenStack Networking service and create a router, and then set an ID of the router created to router_id in the L3 agent configuration file.
$ neutron router-create myrouter1
Created a new router:
+-----------------------+--------------------------------------+
| Field | Value |
+-----------------------+--------------------------------------+
| admin_state_up | True |
| external_gateway_info | |
| id | 338d42d7-b22e-42c5-9df6-f3674768fe75 |
| name | myrouter1 |
| status | ACTIVE |
| tenant_id | 0c236f65baa04e6f9b4236b996555d56 |
+-----------------------+--------------------------------------+
