Configuring distributed SRv6 gateways
About distributed SRv6 gateways
Distributed SRv6 gateways provide Layer 3 forwarding for traffic in different subnets across sites and provide Layer 3 connectivity to the external network.
Distributed SRv6 gateway deployment
As shown in Figure 76 , each site's PE acts as a distributed SRv6 gateway to perform Layer 3
forwarding for the traffic of the local site. A PE acts as a border gateway to the external Layer 3 network. On all the SRv6 gateways and border gateway, you must create VSI interfaces as gateway interfaces. The same VSI interface on multiple SRv6 gateways must be assigned the same IP address. This IP address will be used as the gateway address for users in the EVPN VPLS over
SRv6 network.
Figure 76 Distributed SRv6 gateway deployment
PE
SRv6 GW
EVPN VPLS over SRv6
SRv
6 tunnel
SRv6 tunnel
L3 network
PE
Border
SRv
6 tunnel
PE
SRv6 GW
SRv6 tunnel
PE
SRv6 GW
VTEP
CE
CE CE CE CE CE
Site 1 Site 2 Site 3 Site 4
Site 5
Site 6
Control plane working mechanisms
A distributed SRv6 gateway allocates an End.DT4 or End.DT46 SID to a MAC/IP advertisement route to identify the VPN instance to which the packets that match the route belong.
As shown in Figure 77 , the ARP learning and BGP EVPN route advertisement process is as follows:
1. CE 2 sends an ARP request to obtain the MAC address of the gateway (a VSI interface on PE
2).
2. When PE 2 receives the ARP request from an AC, it identifies the VSI of the AC, and searches for the VSI interface associated with the VSI.
3. PE 2 relies to the ARP request with the MAC address of the VSI interface. At the same time, PE
2 learns the ARP information of CE 2 to the VPN instance bound to the VSI interface and generates a FIB entry for the ARP information.
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