Verify QoS ECN feature configuration.

• 2_router_links.testbed

• Connect DUT port-1 to ATE port-1, DUT port-2 to ATE port-2.
• Create an input IPv4 classifier to match traffic intended for the QoS queue being tested (e.g., using dscp values).
• Apply the classifier to the input of DUT port-1 using /qos/interfaces/interface/input/classifiers/classifier/config/name.
• ECN configuration parameters:
  • This test verifies the DUT's ability to accept an ECN configuration with a vertical buffer utilization cut-off line. If the buffer is utilized below that cut-off value, no packet is ECN CE marked. If the buffer is utilized at or above that cut-off value, all packets are ECN CE marked.
  • An ECN profile can be created for different queues. ECN profiles per queue can be applied to the output side of interfaces.
  • 6.25MB max-threshold is selected as it represents ~500 micro-seconds of Delay bandwidth Buffer on 100GE interfaces. This is O(2%) of buffer depth, hence allows for micro-burst absorption without backpressing senders and at the same time leaves enough DBB to accommodate RTT ECN signaling loop delay in the global network for longer burst/congestion.

• Step 1 - Generate DUT configuration: Configure a queue-management-profile with the following ECN parameters. Attach this profile to the target queue (e.g., queue 0) on the output of DUT port-1.
  • min-threshold: 81920 (80KB)
  • max-threshold: 81920 (80KB)
  • enable-ecn: true
  • drop: false
  • max-drop-probability-percent: 100

{
  "qos": {
    "queue-management-profiles": {
      "queue-management-profile": [
        {
          "name": "ECN_PROFILE_1",
          "config": {
            "name": "ECN_PROFILE_1"
          },
          "wred": {
            "uniform": {
              "config": {
                "min-threshold": "81920",
                "max-threshold": "81920",
                "enable-ecn": true,
                "drop": false,
                "max-drop-probability-percent": 100
              }
            }
          }
        }
      ]
    },
    "interfaces": {
      "interface": [
        {
          "interface-id": "Ethernet1",
          "config": {
            "interface-id": "Ethernet1"
          },
          "output": {
            "queues": {
              "queue": [
                {
                  "name": "0",
                  "config": {
                    "name": "0",
                    "queue-management-profile": "ECN_PROFILE_1"
                  }
                }
              ]
            }
          }
        }
      ]
    }
  }
}

• Step 2 - Push configuration to DUT using gNMI Set with REPLACE option.
• Step 3 - Validation with pass/fail criteria: Validate that the profile is created and the values are set as expected using gNMI Get on the state paths.
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_1]/wred/uniform/state/min-threshold == 81920
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_1]/wred/uniform/state/max-threshold == 81920
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_1]/wred/uniform/state/enable-ecn == true
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_1]/wred/uniform/state/drop == false
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_1]/wred/uniform/state/max-drop-probability-percent == 100
• Step 4 - Validate ECN profile application: Verify that the profile is successfully applied to the output interface queue.
  • Verify /qos/interfaces/interface[interface-id=Ethernet1]/output/queues/queue[name=0]/state/queue-management-profile == ECN_PROFILE_1
• Step 5 - Trigger a supervisor switchover using gNOI SwitchControlProcessor.
• Step 6 - Once the new supervisor is active, repeat the gNMI Get checks from Step 3 and 4 to verify the configuration persisted.

• Step 1 - Generate DUT configuration: Configure a queue-management-profile with the following ECN parameters. Attach this profile to the target queue on the output of DUT port-1.
  • min-threshold: 3276800 (3.125MB)
  • max-threshold: 6553600 (6.250MB)
  • enable-ecn: true
  • drop: false
  • max-drop-probability-percent: 100
• Step 2 - Push configuration to DUT using gNMI Set with REPLACE option.
• Step 3 - Validation with pass/fail criteria: Validate that the profile is created and the values are set as expected using gNMI Get on the state paths.
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_2]/wred/uniform/state/min-threshold == 3276800
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_2]/wred/uniform/state/max-threshold == 6553600
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_2]/wred/uniform/state/enable-ecn == true
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_2]/wred/uniform/state/drop == false
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_2]/wred/uniform/state/max-drop-probability-percent == 100
• Step 4 - Validate ECN profile application: Verify that the profile is successfully applied to the output interface queue.
  • Verify /qos/interfaces/interface[interface-id=Ethernet1]/output/queues/queue[name=0]/state/queue-management-profile == ECN_PROFILE_2

• Step 1 - Generate DUT configuration: Configure a queue-management-profile with the following ECN parameters. Attach this profile to the target queue on the output of DUT port-1.
  • min-threshold-percent: 1 (1%)
  • max-threshold-percent: 2 (2%)
  • enable-ecn: true
  • drop: false
  • max-drop-probability-percent: 100
• Step 2 - Push configuration to DUT using gNMI Set with REPLACE option.
• Step 3 - Validation with pass/fail criteria: Validate that the profile is created and the values are set as expected using gNMI Get on the state paths.
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_3]/wred/uniform/state/min-threshold-percent == 1
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_3]/wred/uniform/state/max-threshold-percent == 2
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_3]/wred/uniform/state/enable-ecn == true
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_3]/wred/uniform/state/drop == false
  • Verify /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_3]/wred/uniform/state/max-drop-probability-percent == 100
• Step 4 - Validate ECN profile application: Verify that the profile is successfully applied to the output interface queue.
  • Verify /qos/interfaces/interface[interface-id=Ethernet1]/output/queues/queue[name=0]/state/queue-management-profile == ECN_PROFILE_3

Ensure that invalid configurations are properly rejected by the DUT.

• Negative Test 1 (min-threshold > max-threshold): Attempt to configure a queue-management-profile where min-threshold is strictly greater than max-threshold (e.g., min-threshold = 81920 and max-threshold = 40960). Verify the gNMI Set is rejected.
• Negative Test 2 (Invalid max-drop-probability-percent): Attempt to configure max-drop-probability-percent to an out-of-range value (e.g., 101). Verify the gNMI Set is rejected.
• Negative Test 3 (Non-existent Profile Assignment): Attempt to assign a non-existent queue-management-profile string (e.g., BOGUS_PROFILE) to /qos/interfaces/interface/output/queues/queue/config/queue-management-profile. Verify the gNMI Set is rejected.
• Negative Test 4 (Invalid Profile Deletion): Apply a valid queue-management-profile to an interface's queue. Then, attempt to delete that queue-management-profile while it is still actively applied to the interface's queue. Verify the deletion is rejected.

• Step 1 - Detach the queue-management-profile from the output queue using gNMI Delete on /qos/interfaces/interface/output/queues/queue/config/queue-management-profile or by sending a Replace with an empty profile.
• Step 2 - Validate the profile is detached by verifying the state path no longer returns the profile name.
• Step 3 - Delete the queue-management-profile entirely using gNMI Delete on /qos/queue-management-profiles/queue-management-profile[name=ECN_PROFILE_1].
• Step 4 - Validate the profile is removed by verifying a gNMI Get on the profile path returns an error or empty result.

The below yaml defines the OC paths intended to be covered by this test. OC paths used for test setup are not listed here.

paths:
  ## Config paths
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/min-threshold:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/max-threshold:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/min-threshold-percent:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/max-threshold-percent:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/enable-ecn:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/weight:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/drop:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/config/max-drop-probability-percent:
  /qos/interfaces/interface/input/classifiers/classifier/config/name:
  /qos/interfaces/interface/output/queues/queue/config/name:
  /qos/interfaces/interface/output/queues/queue/config/queue-management-profile:

  ## State paths:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/min-threshold:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/max-threshold:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/min-threshold-percent:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/max-threshold-percent:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/enable-ecn:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/weight:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/drop:
  /qos/queue-management-profiles/queue-management-profile/wred/uniform/state/max-drop-probability-percent:
  /qos/interfaces/interface/input/classifiers/classifier/state/name:
  /qos/interfaces/interface/output/queues/queue/state/name:
  /qos/interfaces/interface/output/queues/queue/state/queue-management-profile:

rpcs:
  gnmi:
    gNMI.Set:
      Replace:
    gNMI.Get:
  gnoi:
    system.System.SwitchControlProcessor:

• vRX