一、增加nginx.conf配置即可

    server{
        listen 80;
        server_name a.123.com;
        rewrite ^/(.*)$ https://a.123.com:443/$1 permanent;
    }

二、#解决http二级域名跳转https，解决http根域名跳转https

server {
 listen 80;
 server_name test.com;
 if ($host != 'www.test.com') {
 rewrite ^/(.*)$ https://www.test.com/$1 permanent;
 }
}
server {
 listen 80;
 server_name www.test.com;
 rewrite ^/(.*)$ https://www.test.com/$1 permanent;
}