Laravel
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Availability

IPv6 & HTTP/2

Checks that your site works over IPv6 and supports HTTP/2. A broken IPv6 setup makes your site unreachable for many mobile visitors.

How it works

Once a day, we look at how visitors can reach your site:

  • IPv6: when your domain has an AAAA record, we connect over IPv6 and check that the site really answers. Many mobile networks prefer IPv6, so a broken AAAA record makes your site unreachable for many visitors while it still works on your own connection.
  • HTTP/2: we check that the server negotiates HTTP/2, which loads pages with many files much faster than HTTP/1.1.
  • HTTP/3: we read it from the Alt-Svc header the server announces.

Statuses

Status Meaning
OK The site works over IPv6 (or has no AAAA record) and supports HTTP/2.
Warning No IPv6 support, no HTTP/2, or we could not connect.
Failed An AAAA record is set, but the site does not answer over IPv6.

By default you are notified of failures only.

Fixing common problems

  • AAAA record set but no answer over IPv6: either make your web server listen on IPv6 (listen [::]:443 in nginx) and open the firewall, or remove the AAAA record. A wrong AAAA record is worse than none.
  • No HTTP/2: enable it in the web server (http2 on; in nginx, Protocols h2 http/1.1 in Apache) or put a CDN in front of the site.