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Classic Linux vs DirectAdmin

Some of the underlying philosophical difference between the two environments are described here.

User interface

The Classic Linux environment has always been, and will continue to be, oriented towards “old-timers” who prefer a command-line computing environment. Thus the Classic Linux environment tries to provide useful command-line tools. It's expected that as a user in this environment you don't mind reading online manuals now and then (with the “man” command), and you write, or would some day like to write, shell scripts or procmail recipes.

On the other hand, the DirectAdmin environment is intended to be much more point-and-click. You will rarely, if ever, need to log into the Linux shell.

Both environments provide control panels and both will let you add custom domains, email accounts, and websites.

Linux utilities

The Classic Linux environment uses Ubuntu 20.04 LTS. This Linux distribution is filled with latest and greatest tools while still providing a reasonably long lifetime before it becomes unsupported (at least three years, possibly five).

In addition to software development and network debugging utilities, Classic Linux also has traditional text-only games (in /usr/games) (you have to cd there and look, as they are not in you default PATH) and selected nntp clients for usenet access.

The DirectAdmin environment used CentOS 8, which is renowned for its stability and long lifetime (as much as ten years before it becomes unsupported). It includes older and fewer Linux utilities. But since you will rarely use the Linux shell in a DirectAdmin environment, the lack of the latest Linux tools will not matter much, if at all.

There is one notable exception to the above, specific to web-hosting. In the Classic Linux environment, you get a limited choice of PHP versions (currently 7.4 and 8.0). In the DirectAdmin environment you can choose from many different PHP versions (including 5.6, 7.4, and multiple intermediate versions).

Open-ness and privacy

In the Classic Linux environment, there are very few restrictions. As with very old Unix timesharing machines, you can do many things that were considered normal in past times but today may be considered privacy violations. For example, the ps command will let you see everyone's processes, not just your own. The mailq command will show you all queued mail, not just your own. The who command will show you who else is logged in. You can even try to use the write command to directly write to the tty of any other logged-in user, if they have left it writable by others. And so on.

The DirectAdmin environment, on the other hand, is much less open. Each user is in a so-called chroot environment in which they are isolated from other users, can only see their own processes, and cannot see who else might be logged into the Linux shell. They cannot see what is in the mail queue, except in a very limited way from the control panel.

The Classic Linux environment will block very few incoming and outgoing TCP ports, except to the extent needed to keep the system relatively secure. At this time, users may manually make outgoing connections to port 25, so in theory you could manually send outgoing mail without going through the system-provided software (although this is subject to change depending on how much misuse occurs).

The DirectAdmin environment will block almost all ports except those that are considered essential to normal functioning of the system. A user may not make an outgoing connection to port 25. All outgoing mail must be sent via the system-provided software.

Due to the open nature of the Classic Linux environment, it is possible for a user to commit misuse or overload the system. Therefore every user of the Classic Linux envronment is expected to act in a responsible manner and not accidentally or deliberately do something that would overload the system.

In the DirectAdmin environment, things are much more controlled. It is much harder for a reckless user to overload the system.


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classic_linux_vs_directadmin.txt · Last modified: 2021/02/12 09:15 by admin