#debugging
Articles tagged "debugging".
13 articles
HTTP Status Codes Explained: what 404, 500 and 503 really mean
Every status code is your server trying to tell you something. Here's a plain-English guide to the ones you'll actually meet — what they mean, whose fault they are, and what to do about each.
502 Bad Gateway: what it means and how to fix it
A 502 Bad Gateway means the server in front of your app couldn't get a valid response from the app itself. Here's what's really happening, the usual causes, and how to fix — and prevent — it.
Ping, Traceroute & MTR: network troubleshooting basics
When something's slow or unreachable, three classic tools tell you whether it's you, the network, or them. Here's how ping, traceroute and MTR work — and when to reach for each.
503 Service Unavailable: what it means and how to fix it
A 503 means your server is alive but can't handle the request right now — usually overload or maintenance. Here's what's happening, how to fix it, and how to keep it from surprising your users.
504 Gateway Timeout: what it means and how to fix it
A 504 means a proxy waited for your app to respond — and gave up. It's the signature of something slow, not something dead. Here's how to find the slowness and fix it.
403 Forbidden: causes and how to fix it
A 403 means the server understood you perfectly — and is refusing anyway. Here's what causes 'Forbidden', how it differs from 401, and how to track down the fix.
500 Internal Server Error: what it means and how to fix it
500 is the server's way of saying 'something went wrong and I don't know how to explain it.' Here's what causes it, how to find the real error, and how to stop it recurring.
CORS Errors Explained (and how to fix them)
Every web developer meets the dreaded 'blocked by CORS policy' error. It's not a bug — it's a security feature. Here's what CORS is, why the browser blocks your request, and how to fix it properly.
ERR_TOO_MANY_REDIRECTS: causes and how to fix it
When a page keeps redirecting to itself, the browser gives up with 'too many redirects'. Here's why redirect loops happen and the usual culprits behind them.
SSL/TLS Handshake Failed: causes and how to fix it
When the secure connection can't be agreed, you get a handshake failure — and the page never loads. Here's what goes wrong during the TLS handshake, and how to fix each cause.
Mixed Content Warnings: what they are and how to fix them
Your site is on HTTPS, but the padlock has a warning — or images won't load. That's mixed content: a secure page pulling in insecure resources. Here's how to find and fix it.
ERR_CONNECTION_REFUSED: what it means and how to fix it
Connection refused means you reached the server's door — and it slammed shut. Nothing is listening (or something is blocking). Here's how to track down which.
What is Packet Loss? (causes, effects and fixes)
When data packets vanish in transit, calls stutter, games rubber-band and pages crawl — even on a 'fast' connection. Here's what packet loss is, what causes it, and how to track it down.