基于宝塔面板的跨域设置问题：
1.多个子域名无法正常认证。
2.频繁要求登录点击另外子域名自动跳出。
下面是解决问题的配置文件，最后是宝塔面板的全部配置文件。

        location / {

     if ($request_method = 'OPTIONS') {
        # 允许跨域请求
        add_header 'Access-Control-Allow-Origin' '';
          # 允许的请求方法
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        #
        # Custom headers and headers various browsers should be OK with but aren't
        # 允许的请求头
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
        #允许带身份验证信息的跨域请求
            add_header Access-Control-Allow-Credentials true;
        # Tell client that this pre-flight info is valid for 20 days
        # 预检请求的有效期
        add_header 'Access-Control-Max-Age' 1728000;
        add_header 'Content-Type' 'text/plain charset=UTF-8';
        add_header 'Content-Length' 0;
        return 204;
     }

     if ($request_method = 'POST') {
        add_header 'Access-Control-Allow-Origin' '';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
     }

     if ($request_method = 'GET') {
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
     }

}

同时还需开启接收自定义请求头
underscores_in_headers on;
完整的nginx配置如下：

user  www www;
worker_processes auto;
error_log  /www/wwwlogs/nginx_error.log  crit;
pid        /www/server/nginx/logs/nginx.pid;
worker_rlimit_nofile 51200;

stream {
    log_format tcp_format '$time_local|$remote_addr|$protocol|$status|$bytes_sent|$bytes_received|$session_time|$upstream_addr|$upstream_bytes_sent|$upstream_bytes_received|$upstream_connect_time';

    access_log /www/wwwlogs/tcp-access.log tcp_format;
    error_log /www/wwwlogs/tcp-error.log;
    include /www/server/panel/vhost/nginx/tcp/*.conf;
}

events
    {
        use epoll;
        worker_connections 51200;
        multi_accept on;
    }

http
    {
        include       mime.types;
        #include luawaf.conf;

        include proxy.conf;
        lua_package_path "/www/server/nginx/lib/lua/?.lua;;";

        default_type  application/octet-stream;

        server_names_hash_bucket_size 512;
        client_header_buffer_size 32k;
        large_client_header_buffers 4 32k;
        client_max_body_size 50m;

        sendfile   on;
        tcp_nopush on;
        underscores_in_headers on;
        keepalive_timeout 60;

        tcp_nodelay on;

        fastcgi_connect_timeout 300;
        fastcgi_send_timeout 300;
        fastcgi_read_timeout 300;
        fastcgi_buffer_size 64k;
        fastcgi_buffers 4 64k;
        fastcgi_busy_buffers_size 128k;
        fastcgi_temp_file_write_size 256k;
            fastcgi_intercept_errors on;
        gzip on;
        gzip_min_length  1k;
        gzip_buffers     4 16k;
        gzip_http_version 1.1;
        gzip_comp_level 5;
        gzip_types     text/plain application/javascript application/x-javascript text/javascript text/css application/xml application/json image/jpeg image/gif image/png font/ttf font/otf image/svg+xml application/xml+rss text/x-js;
        gzip_vary on;
        gzip_proxied   expired no-cache no-store private auth;
        gzip_disable   "MSIE [1-6]\.";

        limit_conn_zone $binary_remote_addr zone=perip:10m;
        limit_conn_zone $server_name zone=perserver:10m;

        server_tokens off;
        access_log off;

server
    {
        listen 888;
        server_name phpmyadmin;
        index index.html index.htm index.php;
        root  /www/server/phpmyadmin;
        #error_page   404   /404.html;
        include enable-php.conf;

        location ~ .*\.(gif|jpg|jpeg|png|bmp|swf)$
        {
            expires      30d;
        }

        location ~ .*\.(js|css)?$
        {
            expires      12h;
        }

        location ~ /\.
        {
            deny all;
        }

        access_log  /www/wwwlogs/access.log;

        location / {

     if ($request_method = 'OPTIONS') {
        # 允许跨域请求
        add_header 'Access-Control-Allow-Origin' '';
          # 允许的请求方法
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        #
        # Custom headers and headers various browsers should be OK with but aren't
        # 允许的请求头
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
        #允许带身份验证信息的跨域请求
            add_header Access-Control-Allow-Credentials true;
        # Tell client that this pre-flight info is valid for 20 days
        # 预检请求的有效期
        add_header 'Access-Control-Max-Age' 1728000;
        add_header 'Content-Type' 'text/plain charset=UTF-8';
        add_header 'Content-Length' 0;
        return 204;
     }

     if ($request_method = 'POST') {
        add_header 'Access-Control-Allow-Origin' '';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
     }

     if ($request_method = 'GET') {
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
     }

}

    }
include /www/server/panel/vhost/nginx/*.conf;
}