Linux

9 questions

Which distribution to choose?

Ubuntu — for beginners.
Linux Mint — even easier.
Fedora — modern technologies.
Arch — for advanced users.
For server: Ubuntu Server, Debian.

How to manage packages?

Ubuntu/Debian: apt update && apt upgrade.
apt install package.
Fedora: dnf install package.
Arch: pacman -S package.
snap, flatpak — universal.

Basic terminal commands?

ls — list files.
cd — change directory.
cp, mv, rm — copy, move, delete.
sudo — execute as root.
man command — help.

How to give file permissions?

chmod +x script.sh — execute.
chmod 755 file — rwxr-xr-x.
chown user:group file — owner.
Numbers: 4=read, 2=write, 1=execute.
755 = rwxr-xr-x.

How to set up SSH?

ssh-keygen — create keys.
ssh-copy-id user@server — copy public key.
ssh user@server — connect.
Disable password login in sshd_config.
Change port from 22.

Linux: how to set up environment (shell, dotfiles, aliases)?

Start with requirements: what should work, what are the constraints on budget/performance/security. Then choose a solution.

Linux: how to manage systemd services and journalctl logs?

Practice for "Linux": create a checklist (installation, configuration, backup, updates) and go through it once — this reduces the number of "mystical" problems.

Linux: how to work with network, firewall, and security?

Answer for "Linux": updates and backups are more important than fine-tuning. Automate backups and enable 2FA.

Linux: how to automate tasks (cron, bash, Ansible)?

For "Linux": it is useful to look for primary sources (documentation, release notes) and reproduce the problem with a minimal example.