Website Monitoring — Why You Need It and How to Set It Up
Website monitoring is the continuous, automated tracking of a web resource's availability, performance, and proper functioning. Without monitoring, you're the last to know about problems: from users, search console, or revenue drops. With monitoring — within the same minute something goes wrong.
Why Monitoring Matters
Average time to detect a problem without monitoring is 30 minutes to several hours. With monitoring — 1 to 5 minutes. During that time, businesses lose:
- Visitors and conversions — every minute of downtime means lost leads, orders, and signups
- Search rankings — Google demotes sites with frequent or prolonged outages
- User trust — repeated failures create negative experiences
- Revenue — for e-commerce, even 10 minutes of downtime during peak hours can cost significant amounts
What to Monitor
1. Uptime (Availability)
The most basic and important metric. The system sends an HTTP request to the site and checks:
- HTTP status code — 200 means success, 5xx means server error
- Response time (TTFB) — a sudden increase may predict a failure
- Key content presence — the server may return 200 but with an empty page or error in the body
Use the enterno.io HTTP header checker for instant availability and response time checks.
2. SSL Certificate
SSL certificate expiration is one of the most common and entirely preventable causes of downtime. Browsers display a frightening warning, and users leave.
SSL monitoring should alert you:
- 30 days before expiry — planned renewal
- 14 days — if auto-renewal didn't work
- 7 days — critical level
- 1 day — emergency notification
Check your SSL certificate expiration with the enterno.io SSL checker.
3. DNS Records
Unauthorized DNS changes are a serious security threat. DNS monitoring helps detect:
- Domain redirection to a foreign server (A record changes)
- Email hijacking (MX record changes)
- SPF/DKIM/DMARC removal (TXT record changes)
- Domain takeover (NS record changes)
The enterno.io DNS Lookup tool shows all DNS record types for your domain.
4. Page Speed
A slow site means poor UX and lower search rankings. Google PageSpeed анализ are an official ranking factor. Speed monitoring tracks:
- Time to First Byte (TTFB)
- Largest Contentful Paint (LCP)
- First Input Delay (FID) / Interaction to Next Paint (INP)
- Cumulative Layout Shift (CLS)
Check loading speed with the enterno.io PageSpeed analyzer.
5. Ping and Network Connectivity
Ping monitoring reveals network-level issues not always visible through HTTP:
- High network latency
- Packet loss
- Routing problems
- Specific port unavailability
Use enterno.io Ping to check network availability and latency.
How to Choose Check Intervals
| Site Type | Interval | Rationale |
|---|---|---|
| E-commerce, SaaS | 1 minute | Every minute of downtime costs money |
| Corporate website | 3–5 minutes | Balance between detection speed and load |
| Blog, informational | 5–10 minutes | Lower criticality of downtime |
| Internal services | 1–3 minutes | Affects team productivity |
Alert Channels
Monitoring is useless without timely alerts. Main channels:
- Email — universal but slow. Suitable for non-critical notifications
- Telegram — instant delivery, convenient for teams. Enterno.io supports Telegram notifications
- SMS — for critical incidents when there's no internet access
- Webhook — integration with internal systems, Slack, PagerDuty
Alert Escalation
Set up a cascade system: first alert → Telegram, after 15 minutes with no response → SMS, after 30 minutes → phone call. This ensures no problem goes unnoticed.
Incidents and SLA
Monitoring should not only detect problems but also maintain an incident history:
- Start and end time of the outage
- Downtime duration
- Cause (if determined)
- Affected services
This is necessary for SLA (Service Level Agreement) calculations. For example, 99.9% SLA allows no more than 8 hours and 46 minutes of downtime per year.
| SLA | Allowed Downtime per Year | Allowed Downtime per Month |
|---|---|---|
| 99% | 3 days 15 hours | 7 hours 18 minutes |
| 99.9% | 8 hours 46 minutes | 43 minutes 50 seconds |
| 99.95% | 4 hours 23 minutes | 21 minutes 55 seconds |
| 99.99% | 52 minutes 36 seconds | 4 minutes 23 seconds |
Status Page — Transparency for Users
A public status page shows users the current state of services. This reduces support load during incidents and builds trust.
What a status page should contain:
- Current status of each service (operational / issues / outage)
- Incident history
- Uptime for the last 30/90 days
- Response time
How to Set Up Monitoring on enterno.io
- Sign up on enterno.io
- Go to Monitors in your dashboard
- Add your website URL
- Choose a check interval
- Set up Telegram notifications for instant alerts
- Configure a public status page for your clients
Monitoring Checklist
- Uptime checks configured for all critical pages
- SSL certificate monitoring with alerts
- DNS monitoring for unauthorized changes
- Page speed monitoring
- Alert channels configured (at least two)
- Escalation for critical incidents
- Incident history maintained
- Public status page for clients
- Regular review of threshold values
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