What Is HTTP 426 Upgrade Required?
HTTP 426 Upgrade Required explained, and what it means when you see it in CI/CD and deployments.
HTTP 426 means the server refuses the request until the client upgrades to a different protocol.
What it means
A 426 typically means the server requires TLS or a newer protocol version. The Upgrade header indicates what is needed.
When you see it in CI/CD
In CI, a 426 can mean an API now requires HTTPS or a newer TLS version. Update the client URL/scheme or TLS settings.
Key takeaways
- 426 means upgrade required.
- Often requires HTTPS/newer TLS.
- Update the client scheme or TLS.
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