Apache HTTP Server Version 2.5
Apache HTTP Server Version 2.5
| Description: | HTTP/2 support module for
mod_proxy |
|---|---|
| Status: | Experimental |
| Module Identifier: | proxy_http2_module |
| Source File: | mod_proxy_http2.c |
| Compatibility: | Available in httpd 2.4.19 and later |
mod_proxy_http2
supports HTTP/2 only, it does not
provide any downgrades to HTTP/1.1. This means that the backend
needs to support HTTP/2 because HTTP/1.1 will not be used instead.
This module requires the service of mod_proxy, so in order to get the ability of
handling HTTP/2 proxy requests,
mod_proxy and mod_proxy_http2
need to be both loaded by the server.
mod_proxy_http2 works with incoming fronted requests
using HTTP/1.1 or HTTP/2. In both cases, requests proxied
to the same backend are sent over a single TCP connection
whenever possible (namely when the connection can be re-used).
Caveat: there will be no attempt to consolidate multiple HTTP/1.1 frontend requests (configured to be proxied to the same backend) into HTTP/2 streams belonging to the same HTTP/2 request. Each HTTP/1.1 frontend request will be proxied to the backend using a separate HTTP/2 request (trying to re-use the same TCP connection if possible).
This module relies on libnghttp2 to provide the core http/2 engine.
This module is experimental. Its behaviors, directives, and defaults are subject to more change from release to release relative to other standard modules. Users are encouraged to consult the "CHANGES" file for potential updates.
Do not enable proxying until you have secured your server. Open proxy servers are dangerous both to your network and to the Internet at large.
This module provides no directives.
The examples below demonstrate how to configure HTTP/2 for backend connections for a reverse proxy.
ProxyPass "/app" "h2://app.example.com" ProxyPassReverse "/app" "https://app.example.com"
ProxyPass "/app" "h2c://app.example.com" ProxyPassReverse "/app" "http://app.example.com"
The schemes to configure above in
ProxyPassReverse for reverse proxying
h2 (or h2c) protocols are the usual
https (resp. http) as expected/used by
the user agent.
mod_proxy_http creates the following request notes for
logging using the %{VARNAME}n format in
LogFormat or
ErrorLogFormat:
The module does not support the HTTP/2 feature PUSH. Backend servers
that would like to advertise preload resources should send the appropriate
Link headers.
If available, they may do so using the "103 Early Hints"
intermediate responses as specified in
RFC 8297. This will give
the best performance. If the client is talking HTTP/2 as well, this may
then result in a PUSH from Apache to the client or just in forwarding
the 103 response.
