You can host as many domains as you like. When you add a domain you get to choose which user account has control of it’s files.
If you choose to host domain2 under the same user as domain1 then you will see an additional folder in S/FTP called domain2.com the next time you log in. Simply upload domain2 files into that directory and you’re good to go.
If the domains aren’t “sister sites” (ie. are irrelevant to each other) then it can be a good idea to set up a new user within Panel and link domain2 to the new user. In this case you would see domain1 folder when logging in to user1 account and domain2 folder when logging in with user2 account via shell, SSH, FTP, etc.
You still have access to all alter all users/domains via your principal Panel account.
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