Package Management

• Most Linux Distributions offer a centralized way to install software → use a package manager to install, update, and remove software from a centralized repository
• Package manager ensures to keep our system up to date
  • ENOURMOUS benefit of many linux systems
  • A lot of applications no longer need to include their own updater
• How does it work?
  • Our system connects to centralized repositories
  • They provide a list of available packages (including available versions, and their dependencies)
  • The package manager fetches this list and ensures smooth installation/upgrades.
• Slightly different for each distribution
  • but main idea remains the same

In Debian-based distros (ex. Ubuntu)

• We use tool apt to keep system up to date & manage our software
  • related: sudo
  • sudo apt update
    • refreshes the list of available packages
    • should run this before doing anything else with apt
    • should use sudo because you’re accessing directories owned by root\
  • sudo apt upgrade
    • runs a small upgrade of our system
    • small → upgrades existing packages (and when using apt, also allows the install of additional dependencies)
    • X destroys anything
    • Other ways to upgrade
      • sudo apt full-upgrade / sudo apt dist-upgrade
      • large upgrade → upgrades existing packages, removes/installs additional packages (dependencies)
      • potentially destroy/remove stuffs
  • apt autoremove
    • removes packages that are no longer needed
    • you can run this if there’s any errors during an upgrade or full-upgrade
  • apt install [package]
  • apt remove [package]
  • You can use apt-get for update and upgrade (won’t install additional dependencies)

CentOS

• dnf