proxy:

server {
listen some_ip:some_port default;

location / {
add_header X-h1 h1;
add_header X-h2 "h2 h2";
add_header X-h3 h3;
add_header X-h4 h4;
add_header X-h5 h5;
add_header X-h6 "h6 h6";
add_header X-h7 h7;
proxy_pass http://backend;
}
}




space: add a double quotes
add_header X-h2 "h2 h2";

MagicBear