Package management.
WHAT A PACKAGE MANAGER DOES
Installs software with its dependencies, from repositories, and tracks what is installed.
WHY NOT INSTALL FROM SOURCE
Updates, removal and dependency handling become your problem forever.
WHAT THE TWO MAIN FAMILIES ARE
One using apt, on Debian-derived systems One using dnf or yum, on Red Hat-derived systems
WHAT THE COMMON OPERATIONS ARE
Refresh the package lists Install Remove Upgrade everything Search Show information about a package List what a package installed
WHY REFRESHING FIRST MATTERS
Without it you install from a stale list, or fail to find a package that exists.
WHAT A REPOSITORY IS
A source of packages.
WHAT ADDING A THIRD-PARTY ONE RISKS
Packages that conflict with the system's own, and trusting whoever operates it.
WHAT TO PREFER
The distribution's own repositories.
WHAT TO DO BEFORE UPGRADING A PRODUCTION SERVER
Read what will change Take a backup or snapshot Do it in a session that survives disconnection Have a way to recover
WHAT TO NEVER DO ON A CPANEL SERVER
Upgrade packages the control panel manages, outside its own tooling.
WHY
It breaks the panel, sometimes unrecoverably.
