ubuntu minimal系统监控与报警

System Monitoring Tools for Ubuntu Minimal
Ubuntu Minimal systems require lightweight, efficient monitoring tools that minimize resource usage while providing critical insights. Below are top choices categorized by type:

Command-Line Tools (Lightweight, No GUI Required)

• top/htop: Real-time process monitoring with CPU/memory usage, process IDs, and runtime. htop (install via sudo apt install htop) offers a more intuitive interface with color-coded metrics and mouse support, while top is pre-installed and suitable for quick checks.
• vmstat/iostat: System-wide resource statistics. vmstat (reports virtual memory, CPU, disk I/O) and iostat (focuses on disk I/O) are part of the sysstat package (install via sudo apt install sysstat). Use vmstat 1 for 1-second interval updates or iostat -x 1 for detailed disk metrics.
• lm-sensors: Hardware sensor monitoring (temperature, voltage, fan speed). Install with sudo apt install lm-sensors, then run sensors-detect to configure sensors. Use sensors to view real-time readings (e.g., CPU temperature).
• netdata: Real-time web-based monitoring with minimal overhead. Install via bash <(curl -Ss https://my-netdata.io/kickstart.sh), then access http://localhost:19999 in a browser. Provides dashboards for CPU, memory, disk, network, and processes.

Graphical Tools (Requires Desktop Environment)

• Conky: Highly customizable desktop widget for system stats (CPU, memory, disk, network). Install with sudo apt install conky, then configure ~/.conkyrc to display metrics in the desktop corner. Lightweight and supports themes.
• Indicator-SysMonitor: Panel applet for Ubuntu’s GNOME desktop. Shows CPU/memory usage in the top panel and allows custom commands (e.g., disk usage). Add via sudo add-apt-repository ppa:fossfreedom/indicator-sysmonitor, install with sudo apt install indicator-sysmonitor, and run from the application menu.

Script-Based Monitoring (Customizable, Automated)

For minimal systems, bash scripts with cron are ideal for scheduled checks. Below is a sample script to monitor CPU, memory, and disk usage, with alerts sent via email when thresholds are exceeded:

#!/bin/bash
# System Monitoring Script with Alert
CPU_THRESHOLD=80
MEMORY_THRESHOLD=85
DISK_THRESHOLD=90
EMAIL="your_email@example.com"

# Get current usage
CPU_USAGE=$(top -bn1 | grep "Cpu(s)" | awk '{print $2 + $4}')
MEMORY_USAGE=$(free | awk '/Mem/ {printf("%.1f", ($3/$2) * 100)}')
DISK_USAGE=$(df -h / | awk '/\// {print $(NF-1)}')
DISK_USAGE=${DISK_USAGE%\%} # Remove % sign

# Alert function
send_alert() {
    SUBJECT="System Alert: $1 Usage Exceeded Threshold"
    BODY="Current $1 usage: ${2}% (Threshold: ${3}%)\n\n$(date)"
    echo -e "$BODY" | mail -s "$SUBJECT" "$EMAIL"
}

# Check thresholds
if (( $(echo "$CPU_USAGE > $CPU_THRESHOLD" | bc -l) )); then
    send_alert "CPU" "$CPU_USAGE" "$CPU_THRESHOLD"
fi
if (( $(echo "$MEMORY_USAGE > $MEMORY_THRESHOLD" | bc -l) )); then
    send_alert "Memory" "$MEMORY_USAGE" "$MEMORY_THRESHOLD"
fi
if (( $DISK_USAGE > $DISK_THRESHOLD )); then
    send_alert "Disk" "$DISK_USAGE" "$DISK_THRESHOLD"
fi

Setup Instructions:

1. Save the script as ~/monitor_system.sh.
2. Make it executable: chmod +x ~/monitor_system.sh.
3. Install mailutils for email alerts: sudo apt install mailutils.
4. Add to cron for hourly checks: crontab -e and append 0 * * * * ~/monitor_system.sh.

This script checks CPU (threshold: 80%), memory (85%), and disk (90%) usage every hour. If any metric exceeds the threshold, it sends an email alert with the current usage and timestamp.

Advanced Tools (Scalable, Full-Featured)

For larger setups or advanced needs, consider these tools (may require more resources but offer comprehensive features):

• Prometheus + Grafana: Prometheus collects metrics, Grafana visualizes them in dashboards. Install Prometheus with wget https://github.com/prometheus/prometheus/releases/download/v2.30.3/prometheus-2.30.3.linux-amd64.tar.gz, extract, and configure prometheus.yml to scrape system metrics. Grafana (install via sudo apt install grafana) connects to Prometheus for real-time dashboards.
• Monit: Monitors services/processes and restarts them if they fail. Install with sudo apt install monit, configure rules in /etc/monit/conf.d/ (e.g., check process nginx with pidfile /var/run/nginx.pid), and start with sudo systemctl start monit.

Each tool caters to different needs—choose based on your system’s complexity and monitoring goals. For minimal systems, command-line tools and scripts are recommended to avoid unnecessary overhead.