Protocol audit

dn01.ink HTTP/2 test

SEO page with a cached HTTP/2, ALPN and TLS negotiation check.

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HTTP/2 / ALPN result

Negotiation result

HTTP/2 is supported

This endpoint negotiated h2 via ALPN, so modern browsers and clients can use HTTP/2 here.

Supported

Protocol: Protocol: h2
TLS: TLS: TLS 1.2
Cipher: Cipher: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256

HTTP/2 support

Supported

Negotiated protocol

TLS version

TLS 1.2

Cipher

TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256

Remote IP

188.114.96.2

Checked host

dn01.ink

Port

443

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Guides

Practical guides for common HTTP/2 Tester tasks — DNS records, troubleshooting steps, and links to our free tools.

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HTTP/2 Detection Guide for Production Sites
How to confirm HTTP/2 support, read protocol results, and avoid false positives from cached or proxied checks.
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ALPN and HTTP/2 Negotiation Explained
Why ALPN decides whether clients use h2, and how to troubleshoot missing protocol negotiation.
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HTTP/2 TLS Requirements Checklist
Practical TLS requirements for reliable HTTP/2 support on public websites and APIs.
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Common CDN, reverse proxy, and load balancer reasons that HTTP/2 works at one layer but fails at another.
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Browser and Server HTTP/2 Mismatch: How to Debug
Why browser devtools and server checks may disagree about HTTP/2, and how to find the real protocol path.
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Nginx, Apache, and Caddy HTTP/2 Config Checks
Configuration checkpoints for enabling HTTP/2 safely on common web servers.
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HTTP/2 SEO and Performance Impact
How HTTP/2 support affects crawl efficiency, user experience, and page speed diagnostics.
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Back to HTTP/2 Tester

HTTP/2 / ALPN result

HTTP/2 is supported

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Related articles

HTTP/2 Detection Guide for Production Sites

ALPN and HTTP/2 Negotiation Explained

HTTP/2 TLS Requirements Checklist

h2 vs HTTP/1.1: What the Tester Result Means

HTTP/2 CDN and Proxy Issues to Check First

Browser and Server HTTP/2 Mismatch: How to Debug

Nginx, Apache, and Caddy HTTP/2 Config Checks

HTTP/2 SEO and Performance Impact