Fast reroute for ethernet virtual private networks—virtual extensible local area network
Techniques are described for providing fast reroute for traffic in EVPN-VXLAN. For example, a backup PE device of an Ethernet segment is configured with an additional tunnel endpoint address (“reroute tunnel endpoint address”) for a backup path associated with a second split-horizon group that is different than a tunnel endpoint address and first split-horizon group for another path used for normal traffic forwarding. The backup PE device sends the reroute tunnel endpoint address to a primary PE device of the Ethernet segment, which uses the reroute tunnel endpoint address to configure a backup path to the backup PE device over the core network. For example, the primary PE device may install the reroute tunnel endpoint address within its forwarding plane and one or more operations to cause the primary PE device to encapsulate a VXLAN header including the reroute tunnel endpoint address when rerouting the packet along the backup path.
1. A method comprising:
receiving, by a first provider edge (PE) device of an Ethernet segment and from a second PE device of the Ethernet segment that provides a customer edge (CE) device multi-homed to the first PE device and the second PE device with reachability to an Ethernet Virtual Private Network (EVPN) instance, a reroute tunnel endpoint address of the second PE device for a backup path to the second PE device, wherein the reroute tunnel endpoint address of the second PE device is associated with a second split-horizon group that is different than a tunnel endpoint address and a first split-horizon group of the second PE device for another path to the second PE device;
configuring, by a routing component of the first PE device and within a forwarding component of the first PE device, a backup path to the second PE device over a core network, wherein configuring the backup path comprises installing the reroute tunnel endpoint address within the forwarding component and one or more operations causing the forwarding component to encapsulate, to a packet received from the core network, a Virtualized eXtensible Local Area Network (VXLAN) header including the reroute tunnel endpoint address as a destination tunnel endpoint address of the VXLAN header;
receiving, by the forwarding component of first PE device, a packet from the core network; and
rerouting, by the forwarding component of the first PE device and when an access link from the first PE device to the CE device has failed, the packet on the backup path by encapsulating the VXLAN header including the reroute tunnel endpoint address and forwarding the packet including the reroute tunnel endpoint address on the backup path to the second PE device over the core network.
2. The method of claim 1 , wherein receiving the reroute tunnel endpoint address comprises receiving an Ethernet Auto-Discovery route including the reroute tunnel endpoint address.
3. The method of claim 2 , wherein the reroute tunnel endpoint address is included in an Egress Endpoint sub-TLV of a Border Gateway Protocol (BGP) Tunnel Encapsulation Attribute carried in the Ethernet Auto-Discovery route.
4. The method of claim 2 , wherein the reroute tunnel endpoint address is included in a Border Gateway Protocol (BGP) transitive extended community.
5. The method of claim 1 , wherein receiving the reroute tunnel endpoint address comprises receiving a MAC/IP Advertisement route including the reroute tunnel endpoint address.
6. The method of claim 5 , wherein the reroute tunnel endpoint address is included in a Border Gateway Protocol (BGP) transitive extended community.
7. A method comprising:
configuring a first provider edge (PE) device of an Ethernet segment with a reroute tunnel endpoint for a backup path to the first PE device, wherein the Ethernet segment provides a customer edge (CE) device that is multi-homed to the first PE device and a second PE device with reachability to an Ethernet Virtual Private Network (EVPN) instance, and wherein the reroute tunnel endpoint address of the first PE device is associated with a second split-horizon group that is different than a tunnel endpoint address and a first split-horizon group of the first PE device for another path to the first PE device;
sending, by the first PE device, the reroute tunnel endpoint address to a second PE device;
receiving, by the first PE device, a packet encapsulated with a Virtualized eXtensible Local Area Network (VXLAN) header including the reroute tunnel endpoint address as a destination tunnel endpoint address of the VXLAN header; and
sending, by the first PE device, the packet on the Ethernet segment to the CE device.
8. The method of claim 7 , wherein sending the reroute tunnel endpoint address to the second PE device comprises sending an Ethernet Auto-Discovery route including the reroute tunnel endpoint address.
9. The method of claim 8 , wherein the reroute tunnel endpoint address is included in an Egress Endpoint sub-TLV of a Border Gateway Protocol (BGP) Tunnel Encapsulation Attribute carried in the Ethernet Auto-Discovery route.
10. The method of claim 8 , wherein the reroute tunnel endpoint address is included in a Border Gateway Protocol (BGP) transitive extended community.
11. The method of claim 7 , wherein sending the reroute tunnel endpoint address to the second PE device comprises sending a MAC/IP Advertisement route including the reroute tunnel endpoint address.
12. The method of claim 11 , wherein the reroute tunnel endpoint address is included in a Border Gateway Protocol (BGP) transitive extended community.
13. A first provider edge (PE) device of an Ethernet segment, comprising:
a forwarding component; and
a routing component configured to:
receive, from a second PE device of the Ethernet segment, a reroute tunnel endpoint address of the second PE device for a backup path to the second PE device, wherein the Ethernet segment provides a customer edge (CE) device that is multi-homed to the first PE device and the second PE device with reachability to an Ethernet Virtual Private Network (EVPN) instance, and wherein the reroute tunnel endpoint address of the second PE device is associated with a second split-horizon group that is different than a tunnel endpoint address and a first split-horizon group of the second PE device for another path to the second PE device; and
configure, within a forwarding component of the first PE device, a backup path to the second PE device over a core network, wherein configuring the backup path comprises installing the reroute tunnel endpoint address within the forwarding component and one or more operations causing the forwarding component to encapsulate, to a packet received from the core network, a Virtualized eXtensible Local Area Network (VXLAN) header including the reroute tunnel endpoint address as a destination tunnel endpoint address of the VXLAN header; and
wherein, in response to the configuration of the backup path, the forwarding component is configured to:
receive a packet from the core network; and
reroute, when an access link from the first PE device to the CE device has failed, the packet on the backup path by encapsulating the VXLAN header including the reroute tunnel endpoint address and forwarding the packet including the reroute tunnel endpoint address on the backup path to the second PE device over the core network.
14. The first PE device of claim 13 , wherein to receive the reroute tunnel endpoint address, the routing component is configured to receive an Ethernet Auto-Discovery route including the reroute tunnel endpoint address.
15. The first PE device of claim 14 , wherein the reroute tunnel endpoint address is included in an Egress Endpoint sub-TLV of a Border Gateway Protocol (BGP) Tunnel Encapsulation Attribute carried in the Ethernet Auto-Discovery route.
16. The first PE device of claim 14 , wherein the reroute tunnel endpoint address is included in a Border Gateway Protocol (BGP) transitive extended community.
17. The first PE device of claim 13 , wherein to receive the reroute tunnel endpoint address, the routing component is configured to receive a MAC/IP Advertisement route including the reroute tunnel endpoint address.
18. The first PE device of claim 13 , wherein the reroute tunnel endpoint address is included in a Border Gateway Protocol (BGP) transitive extended community.
19. The first PE device of claim 13 , wherein the routing component is further configured to:
configure the first PE device with a reroute tunnel endpoint for a backup path to the first PE device, wherein the reroute tunnel endpoint address of the first PE device is associated with a second split-horizon group that is different than a tunnel endpoint address and a first split-horizon group of the first PE device for another path to the first PE device;
send the reroute tunnel endpoint address to a second PE device;
wherein, in response to the configuration of the backup path, the forwarding component is further configured to:
receive a packet encapsulated with a VXLAN header including the reroute tunnel endpoint address for the backup path to the first PE device as a destination tunnel endpoint address of the VXLAN header; and
send the packet on the Ethernet segment to the CE device.