How can I setup cPanel to control my existing sites?
Can I somehow install CPanel on my already existing VPS without deleting the content it has rn? Its up and running 3 websites
It looks like cPanel requires being installed on a fresh CentOS 7 server, so you wouldn't be able to install it onto an existing Linode that you're already hosting sites from.
If you wanted to setup cPanel to control your existing websites with limited downtime, your best bet may be to deploy a new Linode running CentOS7, install cPanel and migrate your sites over, and then update your DNS records to point the domains to the new Linode.
Once your websites begin getting served from the new Linode, you should be all set to delete the old one.
Linode Support Staff
Can your team help to migrate cPanel to cPanel site transfers ?
Also I hope there is no need to purchase cpanel license separately ..right?
I should start this by saying that I don't work for Linode, and the following is my opinion.
Just from my basic research, you would need to purchase a CPanel license, I can't speak to Linode's offerings regarding migration.
I would personally advise against using cPanel since it uses Apache (not ideal for most use-cases), and it just adds the overhead of an admin panel. It also isn't open source.
I would suggest using NGINX for your server, and if you NEED a panel, look into the many open source panels that are more lightweight, and (more importantly) use NGINX.
If you are only serving static sites, NGINX without any additional panels or plugins works great, and will be significantly faster than Apache. Even if you are looking to host dynamic sites, the LEMP (Linux, NGINX, MariaDB, PHP) stack works great for that. I think Linode even has a LEMP stack one-click plugin.
The recommended webserver changes based on what you are hosting, but (at least with the people I work with) Apache usage is generally not advised, and NGINX is typically recommended, with panels like cPanel and Plesk generally being frowned upon for their high CPU and Memory usage and significantly greater overhead compared to just running NGINX. For smaller projects, Apache sometimes works fine, but once you start growing, you will start to run into problems.