So, this has nothing to do with any particular version of Virtualmin, but is rather a question of methodology. I saw some things quite a while back about whether one should have a single Top-Level Server with many Sub-Servers, versus having many Top-Level Servers, and I’m a little fuzzy on the reason.
My use case: I have a physical server machine (an R630), and I host some stuff (a few small sites/apps, some email, some database stuff) for my own “business” as well as a local nonprofit, as sort of a hobby-contribution type of thing. The sites are not real high-traffic. I am the only server administrator that ever logs into to Virtualmin or Usermin (I use Roundcube for email access). There are no FTP users. I use HE.net for DNS.
Are there any compelling reasons for either of the following use cases over the other?
One Top-Level Server, with all the other domains configured as Sub-Servers beneath it; vs.
All the different domains configured as independent Top-Level Servers
If you’re the only administrator there is pretty much never any reason to do anything other than many top-level servers. You’re root, you can manage them all.
You do need to configure your SSH and/or FTP client to know about all those users, in this case (I just put my ssh public key in all the domain user authorized keys and add the domain and user to my ssh config, and it’s never an issue…when I ssh/scp to a specific domain name, I get logged in automatically with the right user and without needing to know the password). Since you’re root, you don’t need to log in with different users to manage the domains in Virtualmin; you’ll see them all.
Sub-servers put everything under one user. You don’t need or want this except in cases where you need the customer to be able to manage all their own domains (and even then, it may make sense for them to have multiple top-level servers, but that would mean they’d be logging into with different users, too). They aren’t root, so they won’t see all the domains.
There are Reseller accounts in Virtualmin Pro, which allows a non-root user to manage many top-level virtual servers. But, that can also be confusing for folks because that is not an ssh/FTP user, it is only for logging into Virtualmin. All of the command line stuff would need to be done with the domain owner user (back to me recommending you setup an ssh config and authorized_keys files).