apache/modules/http2

The h2 module adds support for the HTTP/2 protocol to the server.

Specifically, it supports the protocols "h2" (HTTP2 over TLS) and "h2c" 
(HTTP2 over plain HTTP connections via Upgrade). Additionally it offers
the "direct" mode for both encrypted and unencrypted connections.

You may enable it for the whole server or specific virtual hosts only. 


BUILD

If you have libnghttp2 (https://nghttp2.org) installed on your system, simply
add 

    --enable-h2

to your httpd ./configure invocation. Should libnghttp2 reside in a unusual
location, add

    --with-nghttp2=<path>

to ./configure. <path> is expected to be the installation prefix, so there
should be a <path>/lib/libnghttp2.*. If your system support pkg-config,
<path>/lib/pkgconfig/libnghttp2.pc will be inspected.

If you want to link nghttp2 statically into the mod_h2 module, you may
similarly to mod_ssl add

    --enable-nghttp2-staticlib-deps

For this, the lib directory should only contain the libnghttp2.a, not its
shared cousins.


CONFIGURATION

The most important configuration options is

    H2Engine On|Off

which can be set on the base server or a virtual host. By default, the
engine is 'Off'. Please see the documentation of mod_h2 for a complete
list and explanation of other options.


TLS CONFIGURATION

If you want to use HTTP/2 with a browser, most modern browsers will support
it without further configuration. However, browsers so far only support
HTTP/2 over TLS and are expecially picky about the certificate and
encryption ciphers used.

Server admins may look for up-to-date information about "modern" TLS
compatibility under: 

  https://wiki.mozilla.org/Security/Server_Side_TLS#Modern_compatibility