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Backend failure detection

When the backend breaks, the page breaks. Your uptime tool will not tell you.

Your backend stalls. Your server starts erroring. Your CDN quietly serves an error page instead of your content. Your uptime tool sees a server that answered and reports everything as fine. Sitewatch opens the page and checks it actually works, so backend failures that break the visitor experience get caught instead of ignored.

  • Detects server errors and pages that stop being reachable
  • Catches redirect loops and pages drifting to the wrong destination
  • Finds missing files caused by backend or deployment failures

01The gap in your stack

Your uptime tool says "up." Your visitors say "broken."

The homepage is reachable

Uptime tools:
Detected
Sitewatch:
Detected

Checkout is erroring while the homepage is fine

Uptime tools:
Only the homepage is pinged
Sitewatch:
Every critical page checked separately

Redirects send visitors in circles

Uptime tools:
Not detected
Sitewatch:
Loops caught and reported

The page lands on an unexpected destination

Uptime tools:
Not detected
Sitewatch:
Redirects followed and verified

Files the page needs went missing

Uptime tools:
Not checked at all
Sitewatch:
Every script, style and image verified

A blip wakes you at 3am

Uptime tools:
Alerts on the first failure
Sitewatch:
Confirmed 2-of-3 times before alerting

The alert tells you what broke

Uptime tools:
Up or down only
Sitewatch:
The page, the component and the cause

02The blind spots

Backend failures uptime tools pretend do not exist.

The page starts erroring

UNAVAILABLE

The backend behind a page fails and it stops loading — while the rest of the site carries on as normal.

UptimePings the homepage — sees nothing wrong.
SitewatchChecks every critical page, not just the front door.

Visitors get stuck in circles

REDIRECT_LOOP

A misconfigured backend bounces visitors between pages until the browser gives up and shows an error.

UptimeFollows the redirect and reports OK.
SitewatchDetects the loop and reports where it starts.

The page lands somewhere else

HOST_DRIFT

Your URL quietly redirects to a parked domain, a staging server or a CDN error page instead of your site.

UptimeSomething answered — reported as up.
SitewatchFollows every redirect and checks where it ends up.

A deploy breaks the page

ASSET_MISSING

A backend release changes where files live, so scripts, styles and images stop being found.

UptimeServer responds — 100% up.
SitewatchRequests every file the page needs and flags the ones that fail.

The server sends the wrong thing

MIME_MISMATCH

A file arrives as the wrong kind of file — an error page where a script should be — so the browser refuses it.

UptimeA response came back, so it looks fine.
SitewatchChecks each file is the kind of file it claims to be.

The page quietly changes

PAGE-DRIFT

A backend issue alters what the page outputs, and it stays wrong until somebody happens to look.

UptimeNo idea the content changed.
SitewatchCompares each check to the last good version and flags the difference.

03Where it breaks

Every way a backend reaches your visitors.

A backend failure rarely announces itself. Select a layer to see how it surfaces — and how Sitewatch catches it.

The page response

availability

How it fails — A page starts erroring or times out while the rest of the site keeps working perfectly.

How Sitewatch detects it — Checks each critical page independently, so one broken route cannot hide behind a healthy homepage.

Redirects

routing

How it fails — Visitors bounce between pages in a loop, or land on a parked domain instead of your site.

How Sitewatch detects it — Follows the full redirect path on every check and reports loops and unexpected destinations.

What the server sends

content type

How it fails — The server returns an error page or raw data where a real webpage or a script should be.

How Sitewatch detects it — Confirms each response is the kind of thing it should be before the browser has to reject it.

Files the page needs

assets

How it fails — A backend deploy moves or drops files, so scripts and styles the page depends on stop being found.

How Sitewatch detects it — Requests every referenced file and flags the ones that no longer resolve.

Page output

integrity

How it fails — A backend fault changes what the page renders without breaking anything outright.

How Sitewatch detects it — Fingerprints the page so unexpected structural changes stand out immediately.

04The full list

Every way a backend failure can break your site

Page-level failures

  • Pages returning server errors or failing to respond at all
  • Pages caught in circular redirects that leave visitors stranded
  • Pages redirecting to an unexpected domain or a parked page
  • URLs that stop serving a webpage and start serving raw data

File-level failures

  • Scripts, stylesheets or images that can no longer be found
  • Files served as the wrong kind of file, which browsers then refuse

05How it works

What happens on every check.

No test scripts. No credentials. Point Sitewatch at your pages and it does the rest — around the clock, from up to 2 regions on Pro.

Start free
  1. 1

    Add your pages

    Enter any URL and Sitewatch opens the page the way a real visitor would.

  2. 2

    Checks what the page needs

    Every script, stylesheet and image is identified and requested to confirm it arrived and is usable.

  3. 3

    Finds a backend failure

    A page erroring, a redirect looping, a file that moved during a deploy — anything that breaks the page for a visitor.

  4. 4

    Confirms before it alerts

    The problem has to fail 2 out of 3 times, so a momentary glitch never wakes anybody up.

  5. 5

    Alerts you with the evidence

    Slack, email, SMS, webhook, PagerDuty or Opsgenie — naming the failure, the affected page and which parts broke.

06What you get

Outcomes, not a feature list.

Know when checkout breaks, even though the homepage is fine.

Most uptime tools watch one URL. A backend failure rarely takes the whole site down — it takes down the one page that makes you money. Sitewatch checks each critical page on its own, so a healthy homepage can never mask a broken checkout.

$ sitewatch check yoursite.com --critical-pages
homepage loaded · 14 files ok
pricing loaded · 11 files ok
/checkout 503 — server error
✕ incident opened · customers cannot pay

Stop chasing alerts that were never real.

A single failed request means nothing — networks blip. Sitewatch re-checks before it wakes you: a problem has to fail two out of three times to become an incident, and one problem creates one alert, not a flood.

▸ /account — redirect loop suspected
attempt 1 loop detected (3 hops)
attempt 2 resolved normally
attempt 3 loop detected (3 hops)
✕ confirmed 2-of-3 · one alert sent

Every page

Critical pages checked separately, not just the homepage.

2-of-3

Retry confirmation before an alert fires, so blips never page you.

6 channels

Slack, email, SMS, webhook, PagerDuty and Opsgenie.

Stop backend failures from reaching your visitors

Free plan. No credit card. 2-minute setup.

07Questions

Backend monitoring questions, answered.