https://www.computerworld.com/article/2871918/how-to-configure-nginx-for-wordpress-multisite-with-subdirectories.html
https://tonyteaches.tech/wordpress-multisite-nginx/
https://wordpress.org/documentation/article/nginx/
------------------------------
si escribo solo esto en el ispconfig trabaja bien 

if (!-e $request_filename) {
        rewrite /wp-admin$ $scheme://$host$request_uri/ permanent;
        rewrite ^(/[^/]+)?(/wp-.*) $2 last;
        rewrite ^(/[^/]+)?(/.*\.php) $2 last;
    }
location / {
        try_files $uri $uri/ /index.php?$args ;
    }

si voy a agregar un nuevo sitio debo agregar este codigo en la parte supeior de mi virtualhost
que para que me ayude un poco instalo el plugin https://wordpress.org/plugins/nginx-helper/
este me da un camino para agregarlo


map $http_host $blogid {
    default 0;
    include /var/www/pathtoyoursite/wp-content/uploads/nginx-helper/map.conf;
}

------------------------------
 Plugin called Nginx Helper. 

SSH to the Nginx site configuration file, on Debian/Ubuntu it's at /etc/nginx/sites-available

Use your favorite text editor to modify the .vhost file of the site you're working on.

At the top of the file, outside the server{} block, add the following map directive using the Nginx map path from Step 3:



map $http_host $blogid {
    default 0;
    include /var/www/pathtoyoursite/wp-content/uploads/nginx-helper/map.conf;
}

cuando adicione esto el fichero .vhost en la parte superior (esa linea se coge del plgin nginx) debo reiniciar el ngnix
OJOJOJOJOKOKO
SI MODIFICO ALGO EN IPSCONFIG DEBO AGREGAR ESAS LINEAS EN LA PARTE SUPERIOR NUEVAMENTE


This will read the blog mappings generated by the Nginx Helper plugin. Including it this way will let the plugin update the mappings file automatically as you add new sites and you won't have to change your Nginx config again.

Finally, still in your .vhost file, add the following Nginx directives at the bottom of the server{} block, replacing any existing Wordpress directives you've already defined, usually following the location @php{} directive:

esto tengo que agregarlo en el ispconfig en website-> options->nginx Directives

location / {
	try_files $uri $uri/ /index.php?$args;
}

location ~ ^/files/(.*)$ {
  try_files /wp-content/blogs.dir/$blogid/$uri /wp-includes/ms-files.php?file=$1 ;
  access_log off; log_not_found off; expires max;
}

location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
	expires 24h;
	log_not_found off;
}

location ^~ /blogs.dir {
	internal;
	alias /var/www/pathtoyoursite/web/wp-content/blogs.dir ;
	access_log off; log_not_found off;      expires max;
}


if (!-e $request_filename) {
	rewrite /wp-admin$ $scheme://$host$uri/ permanent;
	rewrite ^/[_0-9a-zA-Z-]+(/wp-.*) $1 last;
	rewrite ^/[_0-9a-zA-Z-]+(/.*\.php)$ $1 last;
}


