Static route advertisement

1. A method comprising:

receiving, by a provider edge router of an intermediate layer 3 network, configuration data configuring the provider edge router to provide multi-homed layer 2 virtual bridge connectivity to a local customer edge device using an active-standby mode of operation; and

sending, by the provider edge router to a remote provider edge router in response to determining the provider edge router can send layer 2 packets to the local customer edge device, a route advertisement that includes a static route specifying a layer 3 address of the local customer edge device as a next-hop for a layer 3 subnet.

2. The method of claim 1 ,

wherein the configuration data further configures the provider edge router with an integrated routing and bridging (IRB) interface, and

wherein determining the provider edge router can send layer 2 packets to the local customer edge device comprises determining, by the provider edge router, the IRB interface has a layer 3 subnet that includes the layer 3 address of the local customer edge device.

3. The method of claim 2 ,

wherein the configuration data further configures the provider edge router with an Ethernet Virtual Private Network (EVPN) instance for an EVPN that includes the local customer edge device to provide the multi-homed layer 2 virtual bridge connectivity to the local customer edge device using the active-standby mode of operation, and

wherein the configuration data further configures the IRB interface as a routing interface for the EVPN instance.

4. The method of claim 2 , wherein determining the provider edge router can send layer 2 packets to the local customer edge device comprises:

generating, by the provider edge router, a request for a layer 2 address for the layer 3 address of the local customer edge device, the request being generated for output on a bridging domain of the IRB bridging interface; and

receiving, by the provider edge router from the local customer edge device, a reply to the request.

5. The method of claim 4 , wherein the request for a layer 2 address for the layer 3 address of the local customer edge device comprises one of an Address Resolution Protocol request and a Neighbor Discovery Protocol neighbor solicitation.

6. The method of claim 4 , wherein the bridging domain comprises a virtual local area network.

7. The method of claim 1 , wherein determining the provider edge router can send layer 2 packets to the local customer edge device comprises:

generating, by the provider edge router, a request for a layer 2 address for the layer 3 address of the local customer edge device; and

receiving, by the provider edge router from the local customer edge device, a reply to the request.

8. The method of claim 1 , wherein the layer 3 address of the local customer edge device comprises a gateway L3 address for an integrated routing and bridging (IRB) interface, configured in the local customer edge device, that provides reachability to a layer 3 subnet in a customer network that includes the local customer edge device.

9. The method of claim 1 , wherein determining the provider edge router can send layer 2 packets to the local customer edge device comprises determining, by the provider edge router, the provider edge router is an active multi-homing provider edge router for the local customer edge device.

10. The method of claim 1 , wherein determining the provider edge router can send layer 2 packets to the local customer edge device comprises determining, by the provider edge router, the provider edge router is a designated forwarder provider edge router for the local customer edge device.

11. The method of claim 1 ,

wherein the configuration data comprises first configuration data,

wherein the local customer edge device comprises a first local customer edge device,

wherein the remote provider edge router comprises a first remote provider edge router,

wherein the static route comprises a first static route, and

wherein the route advertisement comprises a first route advertisement, the method further comprising:

receiving, by the provider edge router, second configuration data configuring the provider edge router to provide multi-homed layer 2 virtual bridge connectivity to a second local customer edge device using an active-standby mode of operation; and

sending, by the provider edge router to a second remote provider edge router in response to determining the provider edge router is an active multi-homing provider edge router for the second local customer edge device, a second route advertisement, according to a routing protocol, that includes a second static route specifying a layer 3 address of the second local customer edge device and indicates the second static route has a higher local preference for the routing protocol than a default local preference of the provider edge router.

12. A non-transitory computer-readable medium comprising instructions for causing one or more programmable processors of a provider edge router of an intermediate layer 3 network to:

receive configuration data configuring the provider edge router to provide multi-homed layer 2 virtual bridge connectivity to a local customer edge device using an active-standby mode of operation; and

send, to a remote provider edge router in response to determining the provider edge router can send layer 2 packets to the local customer edge device, a route advertisement that includes a static route specifying a layer 3 address of the local customer edge device as a next-hop for a layer 3 subnet.

13. A network device comprising:

one or more processors operably coupled to a memory,

wherein the one or more processors are configured to receive configuration data configuring the network device as a provider edge router of an intermediate layer 3 network to provide multi-homed layer 2 virtual bridge connectivity to a local customer edge device using an active-standby mode of operation, and

wherein the one or more processors are configured to send, to a remote provider edge router in response to determining the network device can send layer 2 packets to the local customer edge device, a route advertisement that includes a static route specifying a layer 3 address of the local customer edge device as a next-hop for a layer 3 subnet.

14. The network device of claim 13 ,

wherein the configuration data further configures the network device with an integrated routing and bridging (IRB) interface, and

wherein the one or more processors are configured to determine the network device can send layer 2 packets to the local customer edge device by determining the IRB interface has a layer 3 subnet that includes the layer 3 address of the local customer edge device.

15. The network device of claim 14 ,

wherein the configuration data further configures the network device with an Ethernet Virtual Private Network (EVPN) instance for an EVPN that includes the local customer edge device to provide the multi-homed layer 2 virtual bridge connectivity to the local customer edge device using the active-standby mode of operation, and

wherein the configuration data further configures the IRB interface as a routing interface for the EVPN instance.

16. The network device of claim 14 , wherein the one or more processors are configured to determine the network device can send layer 2 packets to the local customer edge device by:

generating a request for a layer 2 address for the layer 3 address of the local customer edge device, the request being generated for output on a bridging domain of the IRB bridging interface; and

receiving, from the local customer edge device, a reply to the request.

17. The network device of claim 16 , wherein the request for a layer 2 address for the layer 3 address of the local customer edge device comprises one of an Address Resolution Protocol request and a Neighbor Discovery Protocol neighbor solicitation.

18. The network device of claim 16 , wherein the bridging domain comprises a virtual local area network.

19. The network device of claim 13 , wherein the one or more processors are configured to determine the network device can send layer 2 packets to the local customer edge device by:

generating a request for a layer 2 address for the layer 3 address of the local customer edge device; and

receiving, from the local customer edge device, a reply to the request.

20. The network device of claim 13 , wherein the one or more processors are configured to determine the network device can send layer 2 packets to the local customer edge device by determining the network device is configured as an active multi-homing provider edge router for the local customer edge device.

21. The network device of claim 13 , wherein the one or more processors are configured to determine the network device can send layer 2 packets to the local customer edge device by determining the network device is configured as a designated forwarder provider edge router for the local customer edge device.