🧪 Lab 02 · Querying Live Telemetry via pygnmi & Python

✅ Validated on Python 3.11 & pygnmi.

Time: ~45 minutes · Tools: Python 3, pygnmi library

Quick Start — Step-by-Step Execution Guide (Location: labs/telemetry-lab/)

Step 1 · Deploy the Lab Fabric (if not already running)

cd labs/telemetry-lab
sudo containerlab deploy -t topology.clab.yml --max-workers 1

Step 2 · Launch the Fully Guided Interactive Walkthrough

./run.sh --guided

Alternative Execution Options (Automated Push or Manual CLI)

• Fast Automated Script Push:

  ./run.sh 01          # apply + verify step 01 automatically
  ./run.sh --all       # run all steps in order
  

• Manual Line-by-Line CLI Execution: Interactive CLI shell on any container node:

  docker exec -it clab-telemetry-lab-leaf1 Cli
  

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🧠 Technology Deep Dive: Python gNMI Client (pygnmi)

Python pygnmi allows network engineers to query live gNMI telemetry streams over gRPC and output structured JSON dictionaries:

from pygnmi.client import gNMIclient

host = ("172.20.20.43", "6030")
path = ["openconfig-interfaces:interfaces/interface[name=Ethernet1]/state"]

with gNMIclient(target=host, username="admin", password="password", insecure=True) as c:
    result = c.get(path=path)
    print(result)

{
  "name": "Ethernet1",
  "admin-status": "UP",
  "oper-status": "UP",
  "counters": {
    "in-octets": 1048293,
    "out-octets": 948201
  }
}

✅ DONE when pygnmi retrieves live interface counters in JSON format over gRPC.