D3bris Homepage up, contact page broken? Uptime vs. functional checks
Why a reachable homepage doesn’t mean the website works – and how HTTP uptime, content checks and synthetic browser tests differ.
“But the website is up” – often true, and yet enquiries have stopped. The reason: simple uptime monitoring usually only checks whether the homepage responds. It doesn’t see what happens behind it. This guide explains the three levels of monitoring and helps you judge which one each website needs.
A typical case
After an update of the form plugin, the contact page of a medical practice returns a server error. The homepage is not affected and loads as always. Uptime monitoring reports “up”. Two weeks later the practice asks why no appointment requests have come in.
Cases like this are not unusual on sites with many plugins, custom templates or embedded third-party services. Every subpage can be built differently and break differently.
Level 1: HTTP uptime
What is checked: does the server respond at an address within a set time with a successful HTTP status code (usually 200)?
Reliably detects: server outages, hosting incidents, DNS errors, expired certificates, redirect loops, error pages with status 500 or 503.
Does not detect: errors on pages other than the one checked; pages that return “200 OK” but show the wrong or empty content.
Effort: very low. One address is enough.
Level 2: Key pages with content checks
What is checked: in addition to the homepage, selected subpages are requested. For each, you can set a text that must appear in the delivered HTML – such as “Request an appointment” or the form’s name.
Also detects: errors that only affect individual pages; pages that technically work but have lost their essential content (e.g. after a theme update); pages deleted or renamed by mistake.
Does not detect: whether a form can actually be submitted and whether the message arrives; content that is only created by JavaScript in the browser.
Effort: low. Two or three addresses per website and one stable text each.
This is how D3bris works: up to three pages per website, each with an optional expected text, every 5 minutes.
Level 3: Synthetic browser tests
What is checked: an automated browser plays through a whole journey: open the page, fill in the form, submit, check the confirmation – or add a product to the cart and go through to the payment page.
Also detects: broken forms, checkout errors, problems with JavaScript, cookie banners or embedded services.
Drawbacks: the tests must be written and adjusted whenever the page changes. Forms create real enquiries and shops real order attempts – that has to be agreed with the client. And the tools are considerably more expensive.
Effort: high, per journey and website.
The levels compared
| HTTP uptime | Key pages + text | Browser test | |
|---|---|---|---|
| Server or hosting down | ✓ | ✓ | ✓ |
| Certificate expired | ✓ | ✓ | ✓ |
| Error on the contact page only | – | ✓ | ✓ |
| Button or form disappeared | – | ✓ (if the text is in the HTML) | ✓ |
| Form sends no emails | – | – | partly (up to the confirmation page) |
| Checkout fails | – | – | ✓ |
| Setup effort per website | minutes | minutes | hours |
| Maintenance when pages change | none | rarely | regularly |
Which level for which website?
- Brochure websites without a form: level 1 is usually enough.
- Websites that bring in enquiries or appointments – practices, law firms, trades, service providers: level 2. For most agency clients this offers the best ratio of benefit to effort.
- Shops and booking systems with meaningful revenue: level 2 for breadth, plus level 3 for the one journey that brings in money.
Practical tips for content checks
- Choose a text that only appears when the page works, such as the submit button’s label. Generic texts like the company name often also appear on error pages.
- Avoid texts that change regularly: prices, dates, opening hours.
- Check the page source (“View page source” in the browser) to confirm the text is there. If it only appears in the rendered page, it is generated by JavaScript.
- Update the texts after a relaunch, otherwise you’ll get false alarms.
The full list of checkpoints is in the checklist for agencies. How to set up WordPress sites specifically is covered in WordPress monitoring without a plugin.