FleetLens Agent

A lightweight, cross-platform agent that collects system information from virtual machines and reports it to a FleetLens server.

Collected Data

Category	Details
System	Hostname, operating system, architecture, serial number
Network	IP addresses, network interfaces (name, IPs, MAC address, type)
Software	Installed applications (name, version, publisher, install date)
Users	Local user accounts (username, display name, admin status, last login)

JSON Payload Example

{
  "hostname": "vm-web-01",
  "ip_addresses": ["192.168.1.10"],
  "serial_number": "VMware-42 1a 7b ...",
  "operating_system": "linux",
  "architecture": "amd64",
  "network_interfaces": [
    {
      "name": "eth0",
      "ip_addresses": ["192.168.1.10", "fe80::1"],
      "mac_address": "00:0c:29:1a:7b:3e",
      "type": "ethernet"
    }
  ],
  "software": [
    {
      "name": "nginx",
      "version": "1.24.0-2",
      "publisher": "Debian Nginx Maintainers",
      "installed_at": ""
    }
  ],
  "users": [
    {
      "username": "admin",
      "display_name": "Admin User",
      "is_admin": true,
      "last_login": "2026-02-10 09:15:30"
    }
  ]
}

Installation

From GitHub Releases

Download the latest binary for your platform from the Releases page.

Available builds: Linux (amd64/arm64), Windows (amd64/arm64), macOS (amd64/arm64).

From Source

git clone https://github.com/Pitchouneee/fleetlens-agent.git
cd fleetlens-agent
go build -o fleetlens-agent .

Usage

fleetlens-agent -api <FLEETLENS_SERVER_URL> [-interval <DURATION>]

Flags

Flag	Default	Description
-api	(required)	FleetLens API base URL (e.g. http://fleetlens.example.com:8080)
-interval	24h	Interval between data collection cycles (e.g. 30m, 1h, 24h)

The API URL can also be set via the FLEETLENS_API_URL environment variable.

Examples

# Default: collect and send every 24 hours
fleetlens-agent -api http://fleetlens.example.com:8080

# Collect every hour
fleetlens-agent -api http://fleetlens.example.com:8080 -interval 1h

# Using environment variable
export FLEETLENS_API_URL=http://fleetlens.example.com:8080
fleetlens-agent

Setup as a System Service

Linux (systemd)

Create /etc/systemd/system/fleetlens-agent.service:

[Unit]
Description=FleetLens Agent
After=network-online.target
Wants=network-online.target

[Service]
Type=simple
ExecStart=/usr/local/bin/fleetlens-agent -api http://fleetlens.example.com:8080
Restart=on-failure
RestartSec=10

[Install]
WantedBy=multi-user.target

Then enable and start:

sudo cp fleetlens-agent /usr/local/bin/
sudo systemctl daemon-reload
sudo systemctl enable --now fleetlens-agent

macOS (launchd)

Create ~/Library/LaunchAgents/com.fleetlens.agent.plist:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.fleetlens.agent</string>
    <key>ProgramArguments</key>
    <array>
        <string>/usr/local/bin/fleetlens-agent</string>
        <string>-api</string>
        <string>http://fleetlens.example.com:8080</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>KeepAlive</key>
    <true/>
</dict>
</plist>

Then load:

cp fleetlens-agent /usr/local/bin/
launchctl load ~/Library/LaunchAgents/com.fleetlens.agent.plist

Windows (NSSM)

Using NSSM (Non-Sucking Service Manager):

nssm install FleetLensAgent C:\Program Files\FleetLens\fleetlens-agent.exe -api http://fleetlens.example.com:8080
nssm start FleetLensAgent

Or with PowerShell natively:

New-Service -Name "FleetLensAgent" `
  -BinaryPathName '"C:\Program Files\FleetLens\fleetlens-agent.exe" -api http://fleetlens.example.com:8080' `
  -DisplayName "FleetLens Agent" `
  -StartupType Automatic `
  -Description "FleetLens system information collection agent"

Start-Service FleetLensAgent

Notes

• The agent sends data to POST {api}/api/agents
• Serial number collection may require elevated privileges (run as root/admin)
• The agent runs the first collection immediately on startup, then repeats at the configured interval
• On API failure, the agent logs an error and retries on the next cycle
• The agent shuts down gracefully on SIGINT/SIGTERM