cat /dev/random > /dev/null &

sudo apt-get install libev-dev libssl-dev automake python-docutils flex bison pkg-config
git clone https://github.com/varnish/hitch.git
cd hitch
./bootstrap
./configure --prefix=/opt/hitch/
make
sudo make install

HTTPS:443　　　　　　　　　　　HTTP:80
   ↓　　　　　　　　　　　　　　　↓
Hitch:443--(localhost:81)-->Varnish:80
　　　　　　　　　　　　　　　　　↓
　　　　　　　　　　　　　　　 Origin

#/etc/hitch/hitch.conf
frontend       = "[*]:443"
ciphers        = "ECDHE+RSAGCM:ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:EECDH+HIGH:EDH+HIGH:HIGH:+3DES:!RC4:!MD5:!aNULL:!eNULL:!LOW:!EXP:!PSK:!SRP:!DSS:!KRB5:!DH"
backend        = "[127.0.0.1]:81"
write-proxy-v2 = on
workers        = 2
backlog        = 1024
keepalive      = 3600
syslog         = on
user           = "nobody"
daemon         = on
alpn-protos    = "h2,http/1.1"
pem-file       = "/etc/hitch/******.pem"

/opt/hitch/sbin/hitch --config=/etc/hitch/hitch.conf

-a :80 \
-a 127.0.0.1:81,PROXY \

root@proxy02:~# varnishadm param.set feature +http2

root@proxy02:~# varnishadm param.show feature
feature
        Value is: +esi_disable_xml_check,+http2
        Default is: none

        Enable/Disable various minor features.
           none                       Disable all features.

        Use +/- prefix to enable/disable individual feature:
           short_panic                Short panic message.
           wait_silo                  Wait for persistent silo.
           no_coredump                No coredumps.
           esi_ignore_https           Treat HTTPS as HTTP in
                                      ESI:includes
           esi_disable_xml_check      Don't check of body looks like
                                      XML
           esi_ignore_other_elements  Ignore non-esi XML-elements
           esi_remove_bom             Remove UTF-8 BOM
           https_scheme               Also split https URIs
           http2                      Support HTTP/2 protocol

-p feature=+http2 \

shard.backend(by=KEY,key=shard.key(bereq.http.cookie))

sub vcl_init {
  new ws_cache = directors.shard();
  ws_cache.set_rampup(10s);
  ws_cache.add_backend(ws01);
  ws_cache.add_backend(ws02);
  ws_cache.add_backend(ws03);
  ws_cache.add_backend(ws04);
  ws_cache.reconfigure();
}

sub vcl_recv {
  //x-varnish-hashにはユーザIDとかそんなのが入ってる
  ...
  set req.backend_hint = ws_cache.backend(by=KEY, key=ws_cache.key(req.url + ":" + req.http.host + ":" + req.http.x-varnish-hash));
}

sub vcl_recv {
  if(1){
    set resp.http.foo = "1";
  }
  if(req.backend_hint){
    set resp.http.bar = "1";
  }
}

varnishadm vcl.load a_example_net /etc/varnish/a_examplet_net.vcl
varnishadm vcl.load b_example_net /etc/varnish/b_examplet_net.vcl
varnishadm vcl.load c_example_net /etc/varnish/c_examplet_net.vcl

varnishadm vcl.label vcl_a_example_net a_example_net
varnishadm vcl.label vcl_b_example_net b_example_net
varnishadm vcl.label vcl_c_example_net c_example_net

vcl 4.0;
//最低限1つはバックエンドがないと動かないのでダミー
backend default { .host = "127.0.0.1"; }

sub vcl_recv {
  if(req.http.host ~ "a\.example\.net$"){
    return(vcl(vcl_a_example_net));
  }
  if(req.http.host ~ "b\.example\.net$"){
    return(vcl(vcl_b_example_net));
  }
  if(req.http.host ~ "c\.example\.net$"){
    return(vcl(vcl_c_example_net));
  }
  return (synth(403));
}