Linux 安装 http2 支持

1. 前提：服务器中已有 git，如果没有，输入下面的命令安装

   sudo apt-get install -y tmux curl vim wget htop git
   

2. curl请求一个需使用 http2 的网址，查看响应结果，为http1.1，说明暂时还不支持http2

       vagrant@homestead:~$ curl -I https://nghttp2.org/
   HTTP/1.1 200 OK
   Date: Tue, 28 Mar 2017 04:58:27 GMT
   Content-Type: text/html
   Last-Modified: Mon, 27 Mar 2017 14:39:24 GMT
   Etag: "58d9241c-19ff"
   Accept-Ranges: bytes
   Content-Length: 6655
   X-Backend-Header-Rtt: 0.001072
   Strict-Transport-Security: max-age=31536000
   Server: nghttpx
   Via: 2 nghttpx
   x-frame-options: SAMEORIGIN
   x-xss-protection: 1; mode=block
   x-content-type-options: nosniff
   

   如果强制使用http2请求，无法得到响应

   vagrant@homestead:~$ curl --http2 -I https://nghttp2.org/
   curl: (1) Unsupported protocol
   

3. 安装 nghttp2

   # Get build requirements
   # Some of these are used for the Python bindings
   # this package also installs
   sudo apt-get install g++ make binutils autoconf automake autotools-dev libtool pkg-config \
   zlib1g-dev libcunit1-dev libssl-dev libxml2-dev       libev-dev libevent-dev libjansson-dev \
   libjemalloc-dev cython python3-dev python-setuptools
   
   # Build nghttp2 from source
   git clone https://github.com/tatsuhiro-t/nghttp2.git
   cd nghttp2
   autoreconf -i
   automake
   autoconf
   ./configure
   make
   sudo make install
   

4. 升级最新版的 curl，这里查看curl版本

   cd ~
   sudo apt-get build-dep curl
   wget http://curl.haxx.se/download/curl-7.xx.0.tar.bz2
   tar -xvjf curl-7.xx.0.tar.bz2
   cd curl-7.xx.0
   ./configure --with-nghttp2=/usr/local --with-ssl
   make
   sudo make install
   sudo ldconfig
   

5. 尝试再次连接

   # Try this out first
   curl --http2 -I nghttp2.org
   
   # If you get errors, try setting this constant
   # to tell curl where to find shared libraries
   LD_LIBRARY_PATH=/usr/local/lib /usr/local/bin/curl --http2 -I nghttp2.org
   

6. 连接

   vagrant@homestead:~/curl-7.xx.0$ LD_LIBRARY_PATH=/usr/local/lib /usr/local/bin/curl --http2 -k -I -H "Host: example.com" https://localhost
   HTTP/2.0 403
   server:nginx/1.11.9
   date:Tue, 28 Mar 2017 05:47:10 GMT
   content-type:text/html; charset=utf-8
   content-length:169
   

7. 打印出phpinfo
   curl 的http2 显示 yes，表示成功。否则需要手动安装php的http扩展。