HTTP

5 posts tagged with HTTP.

What `429 Too Many Requests` actually means, and how rate limits really work

Most rate-limit explanations stop at 'you went too fast.' That's true but not useful. Real rate limiters work in five different ways — token bucket, leaky bucket, fixed window, sliding window, concurrency cap — and the headers tell you which one you're hitting, when to retry, and how much budget you have left.

May 11, 2026·12 min

Reading SSL certificate errors: the four most common ones, decoded

ERR_CERT_AUTHORITY_INVALID. NET::ERR_CERT_DATE_INVALID. ERR_CERT_COMMON_NAME_INVALID. ERR_SSL_VERSION_OR_CIPHER_MISMATCH. The browser tells you almost exactly what's wrong if you know how to read it. Here is what each one means, why it happens, and what to do.

May 11, 2026·13 min

The 5xx family: 500 / 502 / 503 / 504 / 520 and what each one is actually telling you

Every 5xx code is a server's way of saying 'something went wrong on our end.' But they are not interchangeable. 502 means upstream; 504 means upstream-but-slow; 503 means deliberately unavailable; 520 means Cloudflare-doesn't-know. Knowing which one you got cuts the bug-hunt by more than half.

May 11, 2026·12 min

Reading an HTTP redirect chain — the underrated debugging skill

When 'is the site down' turns out to be 'the site is fine, but the redirect chain is sending users somewhere unexpected,' the only useful diagnostic is the full hop-by-hop trail. Here's what each step tells you, and the patterns that crop up most often.

May 9, 2026·6 min

Reading HTTP status codes: a non-developer's guide

The five-class shortcut for HTTP status codes (1xx-5xx), the seven specific codes worth knowing, and how to triage what each one means in practice.

May 8, 2026·4 min
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