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Greengrass V2 Edge Walkthrough

Associate zones

Client devices
Greengrass client device — an IoT Thing (here the ESP32-S3) that discovers a core and uses local MQTT. It does not run Nucleus. can use discovery
Greengrass discovery API — HTTPS call with the client certificate that returns associated core connectivity (host, port, CA) for local MQTT. only for cores you associate via BatchAssociateClientDeviceWithCoreDevice.

ESP32-S3client Thing + cert
→
IoT Coreassociate · discovery :8443
←
NUC coreMoquette :8883
③ LAN mTLS to the host:port from discovery
  • Associate the client Thing with the core (cloud API).
  • Discover: client cert → :8443 returns the core's HostAddress + 8883.
  • Connect: client then talks local MQTT to Moquette on the LAN.

1. Associate

Section titled “1. Associate”

Associate the client Thing with the core

Section titled “Associate the client Thing with the core”
Terminal window
aws greengrassv2 batch-associate-client-device-with-core-device \
  --core-device-thing-name "$CORE_THING_NAME" \
  --entries thingName="$CLIENT_THING_NAME"
{
    "associatedClientDevices": [
        {
            "thingName": "gg-edge-wt-dev-esp32-1"
        }
    ],
    "errorEntries": []
}

List associations

Section titled “List associations”
Terminal window
aws greengrassv2 list-client-devices-associated-with-core-device \
  --core-device-thing-name "$CORE_THING_NAME"
{
    "associatedClientDevices": [
        {
            "thingName": "gg-edge-wt-dev-esp32-1",
            "associationTimestamp": "2026-10-04T10:00:00.000000+00:00"
        }
    ]
}

Optional — associate more zone clients

Section titled “Optional — associate more zone clients”

Only if you created $CLIENT_THING_NAME_2 (and optionally _3) on Identities:

Terminal window
aws greengrassv2 batch-associate-client-device-with-core-device \
  --core-device-thing-name "$CORE_THING_NAME" \
  --entries thingName="$CLIENT_THING_NAME_2"
# Third zone:
# aws greengrassv2 batch-associate-client-device-with-core-device \
#   --core-device-thing-name "$CORE_THING_NAME" \
#   --entries thingName="$CLIENT_THING_NAME_3"
{
    "associatedClientDevices": [
        {
            "thingName": "gg-edge-wt-dev-esp32-2"
        }
    ],
    "errorEntries": []
}

2. Prove discovery with curl

Section titled “2. Prove discovery with curl”

Use the client certificate (not the core cert):

Terminal window
GG_DATA_ENDPOINT="greengrass-ats.iot.${AWS_REGION}.amazonaws.com"
curl --cert "$CLIENT_CERTS_DIR/device.pem.crt" \
     --key "$CLIENT_CERTS_DIR/private.pem.key" \
     --cacert "$CLIENT_CERTS_DIR/AmazonRootCA1.pem" \
     "https://${GG_DATA_ENDPOINT}:8443/greengrass/discover/thing/${CLIENT_THING_NAME}" \
  | jq .
{
  "GGGroups": [
    {
      "GGGroupId": "…",
      "Cores": [
        {
          "thingName": "gg-edge-wt-dev-core",
          "Connectivity": [
            {
              "HostAddress": "192.168.1.50",
              "PortNumber": 8883
            }
          ]
        }
      ]
    }
  ]
}

You should see connectivity info for $CORE_THING_NAME (host / port for Moquette
aws.greengrass.clientdevices.mqtt.Moquette — local MQTT broker on the core. Not Mosquitto; client devices connect here over mTLS., typically 8883). If the list is empty, wait for IP detector
aws.greengrass.clientdevices.IPDetector — publishes the core's LAN address so discovery returns a reachable host for Moquette. and re-check association.

Extra zones (optional): same curl, swap in $CLIENT_CERTS_DIR_2 / $CLIENT_THING_NAME_2 (and _3 if used).

Next: Loop component.