Method and system of overlay flow control
In one aspect, A computerized method of a gateway distributing routes learned through routing protocols (RP) into a Border Gateway Protocol (BGP) includes the step of providing a first gateway that receives a route over a routing protocol. The method includes the step of with the first gateway, redistributing the route to one or more peer routers as a BGP route based on one or more specified criteria. The method includes the step of setting a gateway precedence based on the redistribution of the route to the one or more peer routers as the BGP route. The method includes the step of, based on the gateway precedence, setting a second gateway to automatically redistribute the route with different priorities to influence steering of traffic to a preferred gateway.
1. A method for distributing routes by using a router precedence between a set of peer routers, the method comprising:
at a first router of the set of peer routers that connect devices through an external network:
receiving a route through a first routing protocol;
to distribute the route through a second routing protocol to a set of one or more of the peer routers that comprises at least a peer, second router, selecting a high priority, first community value from a prioritized list of community values, said high priority, first community value establishing the first router as a preferred router in a router precedence for forwarding packets according to the route by ensuring that any peer router that receives the route through the first router and the second router uses the first router to forward packets according to the route; and
distributing the route, with the high priority, first community value, through the second protocol to the set of peer routers;
wherein the second router selects a lower priority, second community value from the prioritized list of community values whenever the second router distributes the route through the second protocol to another router.
2. The method of claim 1 , wherein the lower priority, second community value establishes the second router as a less preferred router than the first router in the router precedence for forwarding packets according to the route.
3. The method of claim 1 , wherein the second routing protocol is a Border Gateway Protocol (BGP) protocol and the second router distributes the route with an automatic autonomous systems (AS) path-prepend to further establish the first router as the preferred router in the router precedence.
4. The method of claim 1 , wherein the second routing protocol is a Border Gateway Protocol (BGP) protocol and the prioritized list of community values comprises a user specified set of BGP communities in a priority-order.
5. The method of claim 4 , wherein the user specified set of BGP communities is specified in a priority-order based on a mapping of the set of BGP communities to a Local-Preference on a provider side edge router.
6. The method of claim 4 , wherein selecting the high priority, first community value comprises selecting a highest priority community value available in the priority-order and the second router selects the lower priority, second community value by selecting a next highest priority community value available in the priority-order.
7. The method of claim 1 , wherein the first and second routers are gateway routers and the external network comprises a network of a public cloud provider.
8. The method of claim 1 , wherein the external network further comprises the Internet.
9. A system for distributing routes by using a router precedence between a set of peer routers, the system comprising:
a set of at least one processing unit on a first router in the set of peer routers that connect devices through an external network; and
a non-transitory machine readable medium storing a program that when executed by the set of processing units comprises sets of instructions for:
receiving a route through a first routing protocol;
to distribute the route through a second routing protocol to a set of one or more of the peer routers that comprises at least a peer, second router, selecting a high priority, first community value from a prioritized list of community values, said high priority, first community value establishing the first router as a preferred router in a router precedence for forwarding packets according to the route by ensuring that any peer router that receives the route through the first router and the second router uses the first router to forward packets according to the route; and
distributing the route, with the high priority, first community value, through the second protocol to the set of peer routers;
wherein the second router selects a lower priority, second community value from the prioritized list of community values whenever the second router distributes the route through the second protocol to another router.
10. The system of claim 9 , wherein the lower priority, second community value establishes the second router as a less preferred router than the first router in the router precedence for forwarding packets according to the route.
11. The system of claim 9 , wherein the second routing protocol is a Border Gateway Protocol (BGP) protocol and the second router distributes the route with an automatic autonomous systems (AS) path-prepend to further establish the first router as the preferred router in the router precedence.
12. The system of claim 9 , wherein the second routing protocol is a Border Gateway Protocol (BGP) protocol and the prioritized list of community values comprises a user specified set of BGP communities in a priority-order.
13. The system of claim 12 , wherein the user specified set of BGP communities is specified in a priority-order based on a mapping of the set of BGP communities to a Local-Preference on a provider side edge router.
14. The system of claim 12 , wherein the sets of instructions for selecting the high priority, first community value comprises sets of instructions for selecting a highest priority community value available in the priority-order and the second router selects the lower priority, second community value by selecting a next highest priority community value available in the priority-order.
15. The system of claim 9 , wherein the first and second routers are gateway routers and the external network comprises a network of a public cloud provider.
16. The system of claim 9 , wherein the external network further comprises the Internet.
17. A method for distributing routes by using a Border Gateway Protocol (BGP) protocol and a router precedence between a set of peer routers, the method comprising:
at a first router of the set of peer routers that connect devices through an external network:
receiving, from a second router of the set of peer routers through the BGP protocol, a route with a high priority, first community value selected at the second router from a prioritized list of community values, said high priority, first community value establishing the second router as a preferred router in a router precedence for forwarding packets according to the route; and
selecting, based on the router precedence, a lower priority, second community value from the prioritized list of community values for distributing with the route to ensure that any peer router that receives the route through the first router and the second router uses the second router to forward packets according to the route; and
distributing the route with the lower priority, second community value through the BGP protocol to at least one other router.
18. The method of claim 17 , wherein the lower priority, second community value establishes the first router as a less preferred router than the second router in the router precedence for forwarding packets according to the route.
19. The method of claim 17 , wherein the prioritized list of community values comprises a user specified set of BGP communities in a priority-order based on a mapping of the set of BGP communities to a Local-Preference on a provider side edge router.
20. The method of claim 17 , wherein selecting the high priority, first community value comprises selecting a highest priority community value available in the prioritized list of community values and the second router selects the lower priority, second community value by selecting a next highest priority community value available in the prioritized list of community values.