Linux · System Config, Time & Hardware

A distro ships with its default firewall on and you set up an SSH server — clients still can't reach it. What is the firewall doing and what fixes it?

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More in System Config, Time & Hardware

On Debian or Ubuntu you need a different keyboard layout — which file holds it, and why is editing that file directly the wrong first move?

During install you want to name the machine but pick localhost — why is that the one hostname to never choose?

Which boot loader does nearly every Linux distribution install by default, and where does it typically go?

Coming from Windows, an admin reflexively reboots after editing a config file. When is a reboot actually required on Linux, and what do you do instead?

Where do almost all Linux configuration files live, and how are the files of larger programs kept from cluttering that directory?

You want every change to /etc tracked and individually restorable. What tool automates that, and how often does it capture state?

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