将 wordpress 设置为子路径但在不同的根目录中

Question

主站：example.com位于/var/www/example.com。

Wordpress 博客：example.com/blog在/var/www/blog。

无法让它工作。

server {
    listen 80;

    server_name example.com;

    root /var/www/example.com;

    # Add index.php to the list if you are using PHP
    index Index.html index.html index.htm index.nginx-debian.html;

    location ~* \.(ico|jpg|jpeg|png|gif|swf|css|json|txt|sd|html)$ {
            try_files $uri =404;
            access_log off;
            expires 1d;
    }

    location ~* \.(js)$ {
        gzip_static on;
        gunzip on;
        try_files $uri =404;
        access_log off;
        expires 1d;
    }


    location /blog {
        alias  /var/www/blog/;
        #try_files $uri $uri/ /index.php?q=$request_uri;
        try_files $uri $uri/ @blog;

        location ~ \.php$ {
            fastcgi_split_path_info ^(.*\.php)(.*)$;
            try_files $uri =404;
            include       /etc/nginx/fastcgi_params;
            fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
            fastcgi_param PATH_INFO $fastcgi_path_info;
            fastcgi_param PATH_TRANSLATED $document_root$fastcgi_path_info;
            fastcgi_pass unix:/run/php/php7.4-fpm.sock;
            #fastcgi_index index.php;

             #include the fastcgi_param setting
            include fastcgi_params;
        }
    }

    location @blog {
            rewrite ^/blog(.*) /blog/index.php?q=$1;
    }
}

忘http://example.com/blog了403 Forbidden。看起来alias不适用于try_files。

但即使http://example.com/blog/index.php不起作用。得到了File not found.。