Decomposing a highly available router
Using concepts demonstrated in previous chapters, let's walk through the creation and decomposition of a highly available router. In the following example, I've started out with an external provider network named GATEWAY_NET
and a project network named PROJECT_NET
:

Using the openstack router create
command with the --ha
argument, we can create an HA router named MyHighlyAvailableRouter
:

Upon creation of the HA router, a network namespace was created on up to three hosts running the Neutron L3 agent. In this demonstration, the L3 agent is running on the controller01
and two compute nodes.
In the following screenshot, a router namespace that corresponds to the MyHighlyAvailableRouter
router can be observed on each host:

Neutron automatically created a network reserved for communication between the routers upon creation of the first HA router within a project using the network defined by the l3_ha_net_cidr
configuration option in the L3 agent configuration...