Website Uptime Monitor Script Linux

Monitor websites from your Linux server with a simple uptime checker using curl and email alerts.

What this script does

Checks multiple URLs for HTTP 200 response
Measures response time in milliseconds
Sends email alert when site is down
Logs all checks with timestamps
Run from cron every 5 minutes

Prerequisites

curl installed
Outbound internet access
Optional: mail command

Step 1: Save the script

sudo nano /usr/local/bin/uptime-monitor.sh
sudo chmod +x /usr/local/bin/uptime-monitor.sh

Step 2: Full script (scroll to read)

uptime-monitor.sh

#!/usr/bin/env bash
set -euo pipefail

URLS=("https://blog.gnomeitsolutions.com/" "https://gnomeitsolutions.com/")
TIMEOUT=10
ALERT_EMAIL="[email protected]"
LOG="/var/log/uptime-monitor.log"

log(){ echo "[$(date '+%F %T')] $*" | tee -a "$LOG"; }

check_url(){
  local url="$1"
  local code time
  time=$(curl -o /dev/null -s -w '%{http_code} %{time_total}' --max-time "$TIMEOUT" "$url" || echo "000 0")
  code=$(echo "$time" | awk '{print $1}')
  time=$(echo "$time" | awk '{print $2}')
  if [[ "$code" == "200" || "$code" == "301" || "$code" == "302" ]]; then
    log "OK $url HTTP $code (${time}s)"
  else
    log "DOWN $url HTTP $code"
    [[ -n "$ALERT_EMAIL" ]] && command -v mail >/dev/null && \
      echo "$url returned HTTP $code" | mail -s "DOWN: $url" "$ALERT_EMAIL"
  fi
}

for u in "${URLS[@]}"; do check_url "$u"; done

Scroll inside the box to read the full script.

Step 3: Configure settings

URLS — array of sites to monitor
TIMEOUT — curl timeout seconds
ALERT_EMAIL — alert recipient

Website uptime monitor shell script on Linux

Step 4: Test manually

sudo /usr/local/bin/uptime-monitor.sh

curl -o /dev/null -s -w '%{http_code}' https://blog.gnomeitsolutions.com/

Schedule with cron

sudo crontab -e

Add:

*/5 * * * * /usr/local/bin/uptime-monitor.sh >> /var/log/uptime-monitor.log 2>&1

Website Uptime Monitor Shell Script with Email Alerts

What this script does

Prerequisites

Step 1: Save the script

Step 2: Full script (scroll to read)

Step 3: Configure settings

Step 4: Test manually

Schedule with cron

Related tutorials