Wi-Fi SSID Count Scan Script

Custom Commands
1

1. Introduction

For network engineers and administrators, knowing how many Wi-Fi networks are nearby can be useful for interference analysis, troubleshooting, or coverage planning.
This Bash script scans the Wi-Fi interface, counts the number of unique SSIDs, and reports the result in a NetBeez-friendly format.

Example Use Cases:

  • Identify Wi-Fi congestion in the local area
  • Monitor the number of neighboring networks over time
  • Assist in selecting optimal channels for APs

2. Overview of the Script

This Bash script:

  1. Scans the Wi-Fi interface (wlan0 by default) for nearby networks
  2. Filters out hidden or duplicate SSIDs
  3. Counts the number of unique SSIDs
  4. Outputs the count in a format compatible with NetBeez metrics

Prerequisites:

  • Linux-based NetBeez agent with iw installed
  • Wi-Fi interface capable of scanning (default: wlan0)
  • sudo privileges to run the scan

Expected Output:

  • Number of unique Wi-Fi networks (SSIDs) detected

3. Script Code

#!/usr/bin/env bash

# Perform WiFi scan and count SSIDs
scan_output=$(sudo iw wlan0 scan 2>/dev/null)

# Check if scan was successful
if [ $? -ne 0 ]; then
    echo "ssids_num=0"
    exit 1
fi

# Count unique SSIDs (filter out hidden networks and duplicates)
ssids=$(echo "$scan_output" | grep -E "^\s*SSID:" | grep -v "SSID: $" | sort -u | wc -l)

echo "ssids_num=$ssids"

4. Sample Output

ssids_num=8

5. Closing Remarks

This script provides a quick and automated way to monitor nearby Wi-Fi networks from a NetBeez agent. It is particularly useful for detecting interference or changes in the wireless environment over time.

Extensions you could try:

  • Log SSID counts periodically for trend analysis

  • Record SSID names for further reporting

  • Combine with signal strength metrics to identify weak APs

Share your improvements in the comments so the community can benefit!