Fleet Management: Spawn and Control Multiple Devices

> This notebook demonstrates the Fleet module for managing multiple simulated CPE devices.

Setup

Mix.install([
  {:caretaker, path: "."}
])

alias Caretaker.CPE.Fleet
require Logger

Create a Fleet

The Fleet module manages multiple simulated devices with:

• Configurable device count and profiles
• Staggered spawn timing to avoid thundering herd
• Fleet-wide and per-device operations
• Aggregate metrics and statistics

{:ok, fleet} = Fleet.start_link(
  acs_url: "http://localhost:4000/cwmp",
  count: 10,
  oui_prefix: "DEMO",
  connection_delay: 50,  # ms between spawns
  profiles: [
    {60, :fiber_ont},     # 60% fiber ONTs
    {40, :cable_modem}    # 40% cable modems
  ],
  behaviors: [
    periodic_inform: [interval: 300_000, jitter: 30_000],
    value_change_events: true
  ]
)

Logger.info("Fleet created")
Fleet.stats(fleet)

Spawn All Devices

Devices are spawned with staggered timing to simulate realistic connection patterns.

{:ok, count} = Fleet.spawn_devices(fleet)
Logger.info("Spawned #{count} devices")

# Check fleet statistics
stats = Fleet.stats(fleet)
Logger.info("Total: #{stats.total}, Spawned: #{stats.spawned}")
stats

List and Inspect Devices

# List all device serial numbers
devices = Fleet.list_devices(fleet)
Logger.info("Devices: #{inspect(devices)}")

# Get details for a specific device
first_device = List.first(devices)
{:ok, device_info} = Fleet.get_device(fleet, first_device)
Logger.info("Device #{first_device}: #{inspect(device_info)}")

%{devices: devices, first_device: device_info}

Per-Device Operations

Control individual devices in the fleet.

# Pick a device to work with
[device_serial | _] = Fleet.list_devices(fleet)

# Update a parameter on a specific device
Fleet.update_param(fleet, device_serial, "Device.DeviceInfo.Description", "Test Device")

# Trigger an inform on a specific device
Fleet.trigger_inform(fleet, device_serial, ["4 VALUE CHANGE"])

# Verify the update
{:ok, info} = Fleet.get_device(fleet, device_serial)
Logger.info("Updated device: #{inspect(info)}")

info

Fleet-Wide Operations

Perform operations across all devices simultaneously.

# Update a parameter on ALL devices
Fleet.update_all_params(fleet, "Device.DeviceInfo.ProvisioningCode", "FLEET-001")

# Trigger inform on ALL devices
Fleet.trigger_all_informs(fleet, ["2 PERIODIC"])

Logger.info("Fleet-wide operations complete")

# Check updated stats
Fleet.stats(fleet)

Add a Device Dynamically

Add new devices to a running fleet.

# Add a new device with a specific profile
{:ok, new_serial} = Fleet.add_device(fleet, profile: :fiber_ont)
Logger.info("Added new device: #{new_serial}")

# Verify it's in the fleet
devices = Fleet.list_devices(fleet)
Logger.info("Total devices now: #{length(devices)}")

%{new_device: new_serial, total: length(devices)}

Stop Individual Devices

# Stop a specific device
devices = Fleet.list_devices(fleet)
device_to_stop = List.last(devices)

Fleet.stop_device(fleet, device_to_stop)
Logger.info("Stopped device: #{device_to_stop}")

# Verify it's stopped
remaining = Fleet.list_devices(fleet)
Logger.info("Remaining devices: #{length(remaining)}")

%{stopped: device_to_stop, remaining: length(remaining)}

Fleet Statistics

Get comprehensive metrics about the fleet.

stats = Fleet.stats(fleet)

Logger.info("""
Fleet Statistics:
  Total configured: #{stats.total}
  Currently spawned: #{stats.spawned}
  Stopped: #{stats.stopped}
  Memory usage: #{Float.round(stats.memory_delta_bytes / 1_048_576, 2)} MB
  Memory per device: #{Float.round(stats.memory_per_device_bytes / 1024, 2)} KB
""")

stats

Cleanup

# Stop all devices in the fleet
Fleet.stop_all(fleet)

Logger.info("All devices stopped")

# Final stats
Fleet.stats(fleet)