L3 Routers

L3 routers can be configured in centralized mode only.

In centralized mode, routing is configured only on the border leaf pairs. In contrast, for distributed mode, routing is configured on the corresponding leaf nodes where the endpoints reside.

Note

The Extreme L3 service plug-in does not support routers configured in distributed mode, although the feature was supported in a previous release. The functionality to configure distributed mode is disabled.

When you create a router, the default mode is centralized. You can create a router with or without the --centralized option and achieve the same result. For example, each of these commands creates a router called R2 in centralized mode:

openstack router create R2
openstack router create R2 --centralized

The L3 service plug-in passes this information to EFA. Then, the EFA Tenant Service configures VRF or routing on border leaf devices.

Note

The OpenStack integration works with only one pair of border leaf devices. The centralized routing instance is created on this pair. Ensure that you add only one border leaf pair during fabric creation.