NetNoise

NetNoise is a network monitoring and troubleshooting utility that performs connectivity testing across multiple protocols. It provides automated testing of DNS resolution, ping, traceroute, HTTP/HTTPS connectivity, bandwidth analysis, port scanning, and MTU discovery against configurable targets for network diagnostics and monitoring.

Features

• Network Testing: DNS resolution, ping, traceroute, HTTP/HTTPS connectivity
• Performance Analysis: Bandwidth testing, MTU discovery, port scanning
• Monitoring: Automated scheduling with systemd integration
• Alerting: Email and webhook notifications on failures
• Logging: Structured JSON output with configurable retention
• Configuration: Flexible target lists and test parameters

Quick Reference

# Installation
git clone https://github.com/madebyjake/netnoise.git
cd netnoise
sudo ./install.sh

# Upgrade
make upgrade    # Upgrade netnoise to latest version

# Service Management
make start      # Start monitoring
make stop       # Stop monitoring
make restart    # Restart monitoring
make status     # Check service status

# Configuration
make config     # Edit configuration
make check      # Validate configuration
make regenerate # Regenerate timer after config changes

# Testing & Monitoring
make test       # Run test suite
make manual     # Run manual test
make health     # Show health status
make logs       # View recent logs

# Maintenance
make clean      # Clean old logs and results
make version    # Show version information

Quick Start

Prerequisites

• Linux system with systemd
• Root or sudo access
• Required tools: ping, traceroute, curl, jq, bc, dig or nslookup

Installation

1. Clone the repository:

   git clone https://github.com/madebyjake/netnoise.git
   cd netnoise

2. Install netnoise:

   sudo chmod +x install.sh
   sudo ./install.sh

3. Configure targets:

   sudo nano /opt/netnoise/netnoise.conf

4. Start monitoring:

   sudo systemctl start netnoise.timer

⚠️ Security Reminder

Always review scripts before running with root/sudo privileges!

Upgrading NetNoise

Automatic Upgrade (Recommended)

The easiest way to upgrade netnoise is to use the built-in upgrade functionality:

# Stop the service
sudo systemctl stop netnoise.timer
sudo systemctl stop netnoise.service

# Navigate to your netnoise directory
cd /path/to/netnoise

# Pull the latest changes
git pull origin main

# Reinstall with the new version
sudo ./install.sh

# Start the service
sudo systemctl start netnoise.timer

Manual Upgrade

If you prefer to upgrade manually or need more control:

1. Backup your configuration:

   sudo cp /opt/netnoise/netnoise.conf /opt/netnoise/netnoise.conf.backup

2. Stop the service:

   sudo systemctl stop netnoise.timer
   sudo systemctl stop netnoise.service

3. Update the code:

   cd /path/to/netnoise
   git pull origin main

4. Reinstall:

   sudo ./install.sh

5. Restore your configuration (if needed):

   sudo cp /opt/netnoise/netnoise.conf.backup /opt/netnoise/netnoise.conf

6. Start the service:

   sudo systemctl start netnoise.timer

Upgrade Verification

After upgrading, verify everything is working correctly:

# Check service status
sudo systemctl status netnoise.timer
sudo systemctl status netnoise.service

# Test configuration
sudo /opt/netnoise/netnoise.sh --check

# Run a manual test
sudo /opt/netnoise/netnoise.sh

# Check logs
sudo journalctl -u netnoise.service -f

Configuration Migration

When upgrading, your existing configuration will be preserved. However, new features may require configuration updates:

• New targets: The default configuration may include new monitoring targets
• New settings: Additional configuration options may be available
• Deprecated options: Some old configuration options may be deprecated

Check the project's release notes for detailed upgrade information and breaking changes.

Rollback

If you need to rollback to a previous version:

# Stop the service
sudo systemctl stop netnoise.timer
sudo systemctl stop netnoise.service

# Checkout the previous version
cd /path/to/netnoise
git checkout <previous-version-tag>

# Reinstall
sudo ./install.sh

# Start the service
sudo systemctl start netnoise.timer

Configuration

Edit /opt/netnoise/netnoise.conf to configure monitoring:

# Monitoring targets
TARGETS=(
    # Core Internet Infrastructure
    "google.com"                # Global search/CDN
    "cloudflare.com"            # Major CDN/DNS provider
    "1.1.1.1"                   # Cloudflare DNS (IPv4)
    "8.8.8.8"                   # Google DNS (IPv4)
    
    # DNS Root Servers
    "a.root-servers.net"        # Root DNS server A
    "b.root-servers.net"        # Root DNS server B
    
    # Global Services
    "amazon.com"                # Global e-commerce/CDN
    "microsoft.com"             # Enterprise services
    "github.com"                # Developer platform
    "wikipedia.org"             # Global knowledge base
    
    # CDN Providers
    "fastly.com"                # Major CDN provider
    "akamai.com"                # Major CDN provider
    
    # Network Infrastructure
    "level3.net"                # Major backbone provider
    "he.net"                    # Hurricane Electric (global ISP)
    "cogentco.com"              # Major backbone provider
    "ntt.net"                   # Global backbone provider
    
    # Time Services
    "time.nist.gov"             # NTP time server
)

# Ping settings - Basic connectivity testing
PING_COUNT=4                    # Number of ping packets to send
PING_TIMEOUT=10                 # Timeout per ping in seconds

# Traceroute settings - Network path discovery
TRACEROUTE_MAX_HOPS=30          # Maximum number of hops to trace
TRACEROUTE_TIMEOUT=5            # Timeout per hop in seconds

# DNS resolution test settings - Name resolution testing
DNS_TIMEOUT=5                   # DNS query timeout in seconds
DNS_ENABLED=true                # Enable DNS resolution tests

# Bandwidth test settings - Network performance testing (resource intensive)
BANDWIDTH_ENABLED=false         # Enable bandwidth testing
BANDWIDTH_TIMEOUT=30            # Bandwidth test timeout in seconds
BANDWIDTH_TEST_UPLOAD=false     # Include upload speed testing

# Port scanning test settings - Service availability testing (security sensitive)
PORT_SCAN_ENABLED=false         # Enable port scanning
PORT_SCAN_TIMEOUT=5             # Port scan timeout in seconds
PORT_SCAN_PORTS="22,80,443,25,53,110,143,993,995"  # Ports to scan

# MTU discovery test settings - Maximum transmission unit testing
MTU_ENABLED=false               # Enable MTU discovery
MTU_TIMEOUT=5                   # MTU test timeout in seconds
MTU_MIN=576                     # Minimum MTU to test (bytes)
MTU_MAX=1500                    # Maximum MTU to test (bytes)
MTU_STEP=10                     # MTU test step size (bytes)

# HTTP/HTTPS test settings - Web service connectivity
HTTP_TIMEOUT=10                 # HTTP request timeout in seconds
HTTP_USER_AGENT="netnoise/1.0"  # User agent string for HTTP requests

# Alert settings - Notification configuration
ALERT_ON_FAILURE=true           # Send alerts when tests fail
ALERT_EMAIL=""                  # Email address for alerts (optional)
ALERT_WEBHOOK=""                # Webhook URL for alerts (optional)

# Timer settings - Service scheduling
TIMER_INTERVAL="hourly"         # How often to run tests
# Options: "minutely", "hourly", "daily", "weekly", "monthly"
# Or custom: "*-*-* *:00:00" (every hour), "*-*-* *:*/15:00" (every 15 minutes)
# Or specific: "Mon *-*-* 09:00:00" (every Monday at 9 AM)

# Log retention settings - Log management
LOG_RETENTION_DAYS=30           # Days to retain log files

DNS Testing Configuration

DNS resolution testing can be configured with the following settings:

• DNS_ENABLED: Enable/disable DNS testing (default: true)
• DNS_TIMEOUT: DNS query timeout in seconds (default: 5, range: 1-60)

DNS testing uses dig (preferred) or nslookup as fallback. The test measures:

• DNS resolution time
• IP addresses returned
• Success/failure status

Bandwidth Testing Configuration

Bandwidth testing can be configured with the following settings:

• BANDWIDTH_ENABLED: Enable/disable bandwidth testing (default: false)
• BANDWIDTH_TIMEOUT: Test timeout in seconds (default: 30, range: 5-300)
• BANDWIDTH_TEST_UPLOAD: Enable upload speed testing (default: false)

Bandwidth testing uses curl (preferred) or wget as fallback. The test measures:

• Download speed in Mbps
• Upload speed in Mbps (if enabled)
• Test duration and success/failure status

Note: Bandwidth testing is disabled by default as it can consume significant bandwidth and time.

Port Scanning Configuration

Port scanning can be configured with the following settings:

• PORT_SCAN_ENABLED: Enable/disable port scanning (default: false)
• PORT_SCAN_TIMEOUT: Connection timeout per port in seconds (default: 5, range: 1-30)
• PORT_SCAN_PORTS: Comma-separated list of ports to scan (default: "22,80,443,25,53,110,143,993,995")

Port scanning uses nc (netcat) as the preferred method or /dev/tcp as fallback. The test measures:

• Open ports on the target host
• Connection success/failure for each port
• Total scan duration and statistics

Common Ports:

• 22: SSH
• 80: HTTP
• 443: HTTPS
• 25: SMTP
• 53: DNS
• 110: POP3
• 143: IMAP
• 993: IMAPS
• 995: POP3S

Note: Port scanning is disabled by default as it can be seen as intrusive by some network administrators.

MTU Discovery Configuration

MTU discovery can be configured with the following settings:

• MTU_ENABLED: Enable/disable MTU discovery (default: false)
• MTU_TIMEOUT: Per-test timeout in seconds (default: 5, range: 1-30)
• MTU_MIN: Minimum MTU to test in bytes (default: 576, range: 68-9000)
• MTU_MAX: Maximum MTU to test in bytes (default: 1500, range: 68-9000)
• MTU_STEP: Step size for binary search in bytes (default: 10, range: 1-100)

MTU discovery uses ping -M do (Don't Fragment) with binary search algorithm. The test measures:

• Optimal MTU size for the network path
• Number of tests performed during discovery
• Total discovery time and success/failure status

How it works:

1. Uses binary search between MTU_MIN and MTU_MAX
2. Tests each MTU size with ping -M do -s <payload_size>
3. Finds the largest MTU that doesn't require fragmentation
4. Reports the optimal MTU size for the network path

Note: MTU discovery is disabled by default as it can be time-consuming and may generate significant network traffic.

Timer Configuration

The monitoring interval is configurable via the TIMER_INTERVAL setting:

• Predefined intervals: minutely, hourly, daily, weekly, monthly
• Custom intervals: Use systemd calendar expressions
  • "*-*-* *:00:00" - Every hour
  • "*-*-* *:*/15:00" - Every 15 minutes
  • "*-*-* 09:00:00" - Every day at 9 AM

After changing the timer interval, regenerate the timer:

make regenerate

Usage

Service Management

# Start/stop/restart monitoring
sudo systemctl start netnoise.timer
sudo systemctl stop netnoise.timer
sudo systemctl restart netnoise.timer

# Check status
sudo systemctl status netnoise.timer

# View logs
sudo journalctl -u netnoise.service -f

Enabling Bandwidth Testing

To enable bandwidth testing, edit the configuration file:

# Edit configuration
sudo nano /opt/netnoise/netnoise.conf

# Enable bandwidth testing
BANDWIDTH_ENABLED=true
BANDWIDTH_TIMEOUT=30
BANDWIDTH_TEST_UPLOAD=false  # Optional: enable upload testing

# Restart service to apply changes
sudo systemctl restart netnoise.timer

Enabling Port Scanning

To enable port scanning, edit the configuration file:

# Edit configuration
sudo nano /opt/netnoise/netnoise.conf

# Enable port scanning
PORT_SCAN_ENABLED=true
PORT_SCAN_TIMEOUT=5
PORT_SCAN_PORTS="22,80,443,25,53"  # Customize ports as needed

# Restart service to apply changes
sudo systemctl restart netnoise.timer

Enabling MTU Discovery

To enable MTU discovery, edit the configuration file:

# Edit configuration
sudo nano /opt/netnoise/netnoise.conf

# Enable MTU discovery
MTU_ENABLED=true
MTU_TIMEOUT=5
MTU_MIN=576
MTU_MAX=1500
MTU_STEP=10

# Restart service to apply changes
sudo systemctl restart netnoise.timer

Advanced Features

Configuration Validation:

make check  # Validate configuration

Performance Monitoring:

• Operation timing and resource usage tracking
• Performance logs: logs/netnoise-performance-YYYYMMDD.log

Health Check:

make health  # Show health status

Health data is stored in /opt/netnoise/health.json for monitoring integration.

Viewing Results

# View logs
make logs

# View JSON results
sudo cat /opt/netnoise/results/netnoise-results-$(date +%Y%m%d).json | jq

# View specific target results
sudo cat /opt/netnoise/results/netnoise-results-$(date +%Y%m%d).json | jq '.[] | select(.target == "google.com")'

# View bandwidth test results only
sudo cat /opt/netnoise/results/netnoise-results-$(date +%Y%m%d).json | jq '.[] | select(.target == "google.com") | .bandwidth'

# View port scanning results only
sudo cat /opt/netnoise/results/netnoise-results-$(date +%Y%m%d).json | jq '.[] | select(.target == "google.com") | .ports'

# View MTU discovery results only
sudo cat /opt/netnoise/results/netnoise-results-$(date +%Y%m%d).json | jq '.[] | select(.target == "google.com") | .mtu'

Alerting

Configure alerts in netnoise.conf:

• Email alerts: Set ALERT_EMAIL (requires mail command)
• Webhook alerts: Set ALERT_WEBHOOK for HTTP POST endpoints (Slack, Discord, etc.)

Security Considerations

• Always review scripts before running with sudo/root privileges
• Service runs as root to access network tools (ping, traceroute)
• Logs may contain sensitive network information
• Keep installation directory (/opt/netnoise) secure
• Use strong authentication for alert webhooks

Troubleshooting

Missing Dependencies:

# Ubuntu/Debian
sudo apt install traceroute curl jq bc dnsutils

# CentOS/RHEL
sudo dnf install traceroute curl jq bc bind-utils

# openSUSE
sudo zypper install traceroute curl jq bc bind-utils

# macOS
brew install traceroute curl jq bc

Service Issues:

# Check status
sudo systemctl status netnoise.timer

# Check logs
sudo journalctl -u netnoise.service -n 50

# Test manually
sudo /opt/netnoise/netnoise.sh

# Debug mode
sudo bash -x /opt/netnoise/netnoise.sh

Uninstallation

sudo ./install.sh uninstall

This removes the systemd service, installation directory, and all logs.