方法一：

    rewrite ^(.*)$ https://$host$1 permanent;

方法二：

适用于 80端口和443 配置在同一个 server{}内

    if ($server_port = 80) {

        rewrite ^(.*)$ https://$host$1 permanent;

    }

其他情况， 站点绑定很多域名，只让某个域名跳转:

    set $redirect_https 1;

    if ($server_port = 80) {

        set $redirect_https "${redirect_https}2";

    }

    if ($http_host = 'www.changxingyun.com') {

        set $redirect_https "${redirect_https}3";

    }

    if ($http_host = 'changxingyun.com') {

        set $redirect_https "${redirect_https}3";

    }

    if ($redirect_https = "123") {

        rewrite ^(.*)$ https://$host$1 permanent;

    }

配置示例：

    server {

        listen       80;

        server_name  www.changxingyun.com;

        rewrite ^ https://$http_host$request_uri? permanent;

    }

    server {

        listen      443;

        ssl on;

        ssl_certificate /etc/ssl/cacert.pem;

        ssl_certificate_key /etc/ssl/privkey.pem;

        server_name www.changxingyun.com;  

        server_tokens off;

        location / {

            fastcgi_param   HTTPS               on;

            fastcgi_param   HTTP_SCHEME         https;

        }

    }