TE-3.7: Base Hierarchical NHG Update

Summary

Validate NHG update in hierarchical resolution scenario

Connect ATE port-1 to DUT port-1, ATE port-2 to DUT port-2, ATE port-3 to DUT port-3.
Create a non-default VRF (VRF-1) that includes DUT port-1.
Establish gRIBI client connection with DUT and make it become leader.
Use Modify RPC to install entries per the following order, and ensure FIB ACK is received for each of the AFTOperation:
- Add 203.0.113.1/32 (default VRF) to NextHopGroup (NHG#42 in default VRF) containing one NextHop (NH#40 in default VRF) that specifies DUT port-2 as the egress interface and 00:1A:11:00:1A:BC as the destination MAC address.
- Add 198.51.100.0/24 (VRF-1) to NextHopGroup (NHG#44 in default VRF) containing one NextHop (NH#43 in default VRF) specified to be 203.0.113.1/32 in the default VRF.
Ensure that ATE port-2 receives the packets with 00:1A:11:00:1A:BC as the destination MAC address.
Use the Modify RPC with ADD operation to test NHG implicit in-place replace (step by step as below):
1. Add a new NH (NH#41) with egress interface that specifies DUT port-3 as the egress interface and 00:1A:11:00:1A:BC as the destination MAC address.
2. Add the same NHG#42 but reference both NH#40 and NH#41.
3. Validate that both ATE port-2 and ATE port-3 receives the packets with 00:1A:11:00:1A:BC as the destination MAC address.
4. Add the same NHG#42 but reference only NH#41.
5. Validate that only ATE port-3 receives the packets.
6. Add the same NHG#42 but reference only NH#40.
7. Validate that only ATE port-2 receives the packets

Repeat the above tests with one additional scenario with the following changes, and it should not change the expected test result.

Add an empty decap VRF, DECAP_TE_VRF.
Add 4 empty encap VRFs, ENCAP_TE_VRF_A, ENCAP_TE_VRF_B, ENCAP_TE_VRF_C and ENCAP_TE_VRF_D.
Replace the existing VRF selection policy with vrf_selection_policy_w as in https://github.com/openconfig/featureprofiles/pull/2217

For prefix:

Parameters:

rpcs:
  gnmi:
    gNMI.Get:
    gNMI.Set:
    gNMI.Subscribe:
  gribi:
    gRIBI.Get:
    gRIBI.Modify:
    gRIBI.Flush:

vRX if the vendor implementation supports FIB-ACK simulation, otherwise FFF.

Validate NHG update in Drain Implementation Test.

Steps:
Topology
- [ATE port-1] — [port-1 DUT port-2] — [port-2 ATE] Port-3]—-[port-3 ATE] Port-4]—-[port-4 ATE]
DUT port-2, port-3 and port-4 are each making a one-member trunk port (trunk-2 and trunk-3, trunk-4).
Configure a destination network-a connected to trunk-2, trunk-3 and trunk-4.
gRIBI installs the following routing structure (700 IPv4 prefix, NHG and NH numbers stays the same as the illustration), and expect FIB ACKs:
In the DEFAULT VRF: VIP1 -> NHG#1 -> [NH#1 {mac: MagicMAC, interface: DUTPort2Trunk}, NH#2 {mac: MagicMAC, interface: DUTPort3Trunk}] NHG#10 -> NH#10 {decap, network-instance: DEFAULT VRF} NHG#20 -> [ NH#20{ip: VIP1}, backupNH: NHG#10]
In a non-defualt VRF, VRF-1: IPv4Entries(1000 /32 IPv4 entries) -> NHG#20
Send 10K IPinIP traffic flows from ATE port-1 to network-a.
Validate that traffic is going via trunk-2 and trunk-3 and there is no traffic loss.
Send one gRIBI NHG#1 update to replace NH#1 and NH#2 with NH#3 pointing to trunk#4.
Expect FIB ACKs, and validate that all traffic are moved to trunk#4 with no traffic loss.
Send one gRIBI NHG#1 update to revert back the changes above.
Expect FIB ACKs and validate that the traffic is moved back to trunk-2 and trunk-3 with less than ms traffic loss.