Is there a way to migrate the site from a master server to the slave, some isp module or do I have to copy it manually?
No. I do it manually, set site to not active, dump database, tar gz files. Copy to other web server, create website, database user and database, import database, untar files and change owner and group owner.
Have a look here: https://www.howtoforge.com/communit...g-one-site-inside-a-multi-server-setup.86613/
