Uptime monitoring involves regularly checking if your website is accessible and responding correctly. When your site goes down, uptime monitoring alerts you immediately so you can respond quickly.
How uptime monitoring works
- Automated checks are sent to your website at regular intervals
- The system verifies the response (status code, content, response time)
- If the check fails, an alert is triggered
- Multiple locations are often used to avoid false positives
Key uptime monitoring features
- Check intervals: How often the system checks your site (1-5 minutes)
- Multiple locations: Checks from different geographic regions
- Alert channels: Email, Slack, SMS, webhooks
- SSL monitoring: Alerts before certificates expire
Calculating uptime percentage
Uptime percentage = (Total time - Downtime) / Total time × 100
Common uptime SLAs:
- 99.9% = 8.76 hours downtime per year
- 99.99% = 52.6 minutes downtime per year
- 99.999% = 5.26 minutes downtime per year
VitalSentinel Uptime Monitoring
VitalSentinel monitors your website from multiple global locations with check intervals as low as 1 minute, alerting you via email or Slack when issues are detected.
Related Terms
Downtime
Periods when a website or service is unavailable or not functioning properly for users.
HTTPS
Hypertext Transfer Protocol Secure, an extension of HTTP that uses encryption to secure communication between browser and server.
Server Response Time
The time it takes for a server to respond to a request from a browser, measured from request initiation to receiving the first byte of response.
SSL Certificate
A digital certificate that authenticates a website's identity and enables an encrypted connection between a web server and browser.