Today, when we create an external gateway for a logical router, svc-monitor creates a new route table with default route pointing to the snat service instance and links it to each of the private networks. Then schema transformer creates a static route in the internal left VN of the service instance with route targets taken from each of the client VNs.
Because of this implementation, svc-monitor has to watch networks being added to logical router and update links to the route table accordingly. Also, schema transformer then has to update the static route with the new set of route targets.
The new proposal is to create a link between logical router and route table. Schema transformer will, then create static routes with the route target only of route targets linked to the logical router. Since all client VNs already import logical router's route targets, they will still get the routes without the additional churn in the config.
Additionally, when svc-monitor comes up, it should delink the route tables from client VNs and link it to the logical-router to keep things consistent.
Review in progress for https:/
Submitter: Suresh Balineni (<email address hidden>)