<?xml version="1.0"?>

<!--
  Copyright (C) Nginx, Inc.
  -->

<!DOCTYPE module SYSTEM "../../../../dtd/module.dtd">

<module name="Module ngx_http_v2_module"
        link="/en/docs/http/ngx_http_v2_module.html"
        lang="en"
        rev="1">

<section id="summary">

<para>
The <literal>ngx_http_v2_module</literal> module (1.9.5) provides
support for <link url="https://tools.ietf.org/html/rfc7540">HTTP/2</link>
and supersedes the
<link doc="ngx_http_spdy_module.xml">ngx_http_spdy_module</link> module.
</para>

<para>
This module is not built by default, it should be enabled with
the <literal>--with-http_v2_module</literal>
configuration parameter.
</para>

<para>
<note>
This module is also available as part of our
<commercial_version>commercial subscription</commercial_version>
in the <literal>nginx-plus-http2</literal> package of NGINX Plus
<link url="https://www.nginx.com/blog/nginx-plus-r7-released/">release 7</link>.
</note>
</para>

</section>


<section id="example" name="Example Configuration">

<para>
<example>
server {
    listen 443 ssl http2;

    ssl_certificate server.crt;
    ssl_certificate_key server.key;
}
</example>
<note>
Note that in order to accept both
<link doc="ngx_http_ssl_module.xml">HTTPS</link> and HTTP/2 connections
simultaneously on the same port, the
<link url="http://www.openssl.org">OpenSSL</link> library used should support
the “Application-Layer Protocol Negotiation” (ALPN) TLS extension
available only since OpenSSL version 1.0.2.
Accepting both types of connections with the
“Next Protocol Negotiation” (NPN) TLS extension available since OpenSSL
version 1.0.1 is possible but not guaranteed.
</note>
</para>

</section>


<section id="directives" name="Directives">

<directive name="http2_chunk_size">
<syntax><value>size</value></syntax>
<default>8k</default>
<context>http</context>
<context>server</context>
<context>location</context>

<para>
Sets the maximum size of chunks
into which the response body is sliced.
A too low value results in higher overhead.
A too high value impairs prioritization due to
<link url="http://en.wikipedia.org/wiki/Head-of-line_blocking">
HOL blocking</link>.
</para>

</directive>


<directive name="http2_idle_timeout">
<syntax><value>time</value></syntax>
<default>3m</default>
<context>http</context>
<context>server</context>

<para>
Sets the timeout of inactivity after which the connection is closed.
</para>

</directive>


<directive name="http2_max_concurrent_streams">
<syntax><value>number</value></syntax>
<default>128</default>
<context>http</context>
<context>server</context>

<para>
Sets the maximum number of concurrent HTTP/2 streams
in a connection.
</para>

</directive>


<directive name="http2_recv_buffer_size">
<syntax><value>size</value></syntax>
<default>256k</default>
<context>http</context>

<para>
Sets the size of the per worker input buffer.
</para>

</directive>


<directive name="http2_recv_timeout">
<syntax><value>time</value></syntax>
<default>30s</default>
<context>http</context>
<context>server</context>

<para>
Sets the timeout for expecting more data from the client,
after which the connection is closed.
</para>

</directive>

</section>


<section id="variables" name="Embedded Variables">

<para>
The <literal>ngx_http_v2_module</literal> module
supports the following embedded variables:
<list type="tag" compact="no">

<tag-name id="var_http2"><var>$http2</var></tag-name>
<tag-desc>
negotiated protocol identifier:
“<literal>h2</literal>” for HTTP/2 over TLS,
“<literal>h2c</literal>” for HTTP/2 over cleartext TCP,
or an empty string otherwise.
</tag-desc>

</list>
</para>

</section>

</module>