Checking your network once is good. Keeping an eye on it continuously is better. This guide shows you how to set up netglance as an always-on guardian that watches your network and tells you when something changes — a new device appears, your speed drops, or a security check fails.

Why continuous monitoring matters¶

Networks change constantly. Devices come and go. ISP performance fluctuates. That smart camera you set up last year might have a new vulnerability. Without monitoring, you'd never know until something breaks.

graph LR
    Check["Run checks"] --> Store["Store results"]
    Store --> Compare["Compare to<br/>baseline"]
    Compare --> Alert["Alert on<br/>changes"]
    Alert --> Fix["Investigate<br/>and fix"]
    Fix --> Check

    style Alert fill:#f5a623,color:#000

Here's what continuous monitoring catches:

• New device on your network — someone connected, or a device you forgot about woke up
• Speed degradation over time — your ISP is giving you less than you pay for
• Security changes — a device changed its open ports, DNS started leaking, WiFi encryption downgraded
• Outages and patterns — your internet drops every Tuesday at 3 PM (ISP maintenance?)

Step 1: Run a full health report¶

Start by understanding your network's current state:

netglance report

Network Health Report
─────────────────────────────────────────────────────────
Discover     ✓ 8 devices found
DNS          ✓ No leaks, DNSSEC enabled
Ping         ✓ Gateway 3ms, Google 15ms
Speed        ⚠ Download 45 Mbps (plan: 100 Mbps)
WiFi         ✓ WPA2, signal -52 dBm, channel clear
TLS          ✓ All certificates valid
ARP          ✓ No spoofing detected
HTTP         ✓ No proxy detected
Firewall     ✓ Inbound filtered

Overall:     GOOD (1 warning)

The report runs every module and gives you a summary. The warning icons tell you what needs attention — in this case, speed is lower than expected.

Step 2: Save a baseline¶

A baseline is a snapshot of "normal" for your network. It's what you compare future scans against:

netglance baseline save

Baseline saved
──────────────────────────────────────────────────
Devices:     8 devices recorded
Timestamp:   2025-03-15 10:30:00
Location:    ~/.config/netglance/netglance.db

Step 3: Set up the daemon¶

The daemon runs checks automatically on a schedule, storing results in the database:

# Install and start the daemon
netglance daemon install
netglance daemon start

Daemon Status
──────────────────────────────────────────────────
Status:      running
Schedule:    every 30 minutes
Next run:    10:30:00
Last run:    10:00:00 (all checks passed)
Results:     stored in ~/.config/netglance/netglance.db

What the daemon checks by default:

You can customize the schedule in ~/.config/netglance/config.yaml.

Step 4: Set up alerts¶

Tell netglance what conditions should trigger a notification:

# Alert when a new device appears
netglance alert add --metric devices --condition "new_device"

# Alert when speed drops below threshold
netglance alert add --metric speed --condition "download < 25"

# Alert when latency spikes
netglance alert add --metric ping --condition "avg > 100"

# Alert on any security finding
netglance alert add --metric security --condition "any_warning"

Active Alerts
──────────────────────────────────────────────────
1. New device detected        → notify
2. Download speed < 25 Mbps   → notify
3. Ping latency > 100 ms      → notify
4. Security warning            → notify

Step 5: Review metrics over time¶

After the daemon has been running for a while, you can query historical data:

# See speed trends over the past week
netglance metrics speed --period 7d

# Check latency over the past 24 hours
netglance metrics ping --period 24h

# View device count over time
netglance metrics devices --period 30d

Download Speed — Last 7 Days
──────────────────────────────────────────────────
100 ┤
 80 ┤          ╭──╮
 60 ┤    ╭─────╯  ╰──╮        ╭──────
 40 ┤────╯            ╰────────╯
 20 ┤
  0 ┤
    Mon  Tue  Wed  Thu  Fri  Sat  Sun

Average: 62 Mbps  |  Min: 38 Mbps  |  Max: 95 Mbps

Patterns to look for:

• Consistent drops at same time — ISP congestion (usually evenings)
• Gradual decline over weeks — ISP throttling or equipment degradation
• Sudden permanent drop — ISP plan change, or equipment failure
• Spikes in device count — unauthorized access or a smart home device misbehaving

Step 6: Check for changes¶

Compare current state against your saved baseline:

netglance baseline diff

Changes since baseline (saved 7 days ago)
──────────────────────────────────────────────────
Devices:
  + NEW:  192.168.1.30 (Espressif) — smart plug?
  - GONE: 192.168.1.15 (Apple) — iPad went offline

Network:
  ~ Speed: was 95 Mbps, now 62 Mbps (35% decrease)
  ~ WiFi channel: was 6, now 11 (auto-switched)

Security:
  ✓ No new security concerns

Recommended monitoring setup¶

Here's what I recommend for most home networks:

graph TD
    A["Install netglance"] --> B["Run initial report"]
    B --> C["Review and fix<br/>any warnings"]
    C --> D["Save baseline"]
    D --> E["Start daemon"]
    E --> F["Set up alerts"]
    F --> G["Weekly: review<br/>metrics dashboard"]
    G --> H["Monthly: update<br/>baseline"]
    H --> G

    style D fill:#4a90d9,color:#fff
    style F fill:#f5a623,color:#000

Daily (automatic via daemon):

• Latency and connectivity checks every 5 minutes
• Device discovery every 30 minutes
• ARP monitoring every 5 minutes

Weekly (manual, takes 2 minutes):

• Review netglance metrics for trends
• Check netglance baseline diff for changes
• Glance at any triggered alerts

Monthly (manual, takes 5 minutes):

• Run a full netglance report
• Update your baseline if changes are expected
• Review your alert thresholds

Deployment options¶

Want netglance running 24/7 without keeping a terminal open? Several options:

A Raspberry Pi is the most popular choice — it's cheap, silent, low-power, and can monitor your network around the clock.

Quick reference¶

Next steps¶

• What's on My Network? — do a thorough initial audit before setting your baseline
• Is My Internet Actually Slow? — diagnose speed and latency issues before setting alert thresholds
• Raspberry Pi deployment — set up a dedicated monitoring device for under $50