systemd and Services
DevOpsLinux

systemd and Services

systemd is the init system that controls every service on modern Linux. Learn systemctl to start/stop/restart services, have them auto-start at boot, write your own unit files, and view logs with journalctl.

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KaiMay 23, 2026
SSH and File Transfer: ssh, scp, rsync
DevOpsSecurity

SSH and File Transfer: ssh, scp, rsync

How you actually get into a remote Linux server: SSH with key authentication (safer than passwords), a handy config file, and transferring files with scp and rsync. A foundational skill for everything you do on a server.

K
KaiMay 23, 2026
Basic Networking on Linux
DevOpsNetworking

Basic Networking on Linux

View IP addresses and routing (ip), check which ports are listening (ss), test connections (ping, curl), and understand name resolution (DNS, /etc/hosts). Enough to diagnose most networking issues on a server.

K
KaiMay 23, 2026· 2 views
Users, Groups and sudo
DevOpsSecurity

Users, Groups and sudo

Linux is multi-user by design. This article explains where users and groups are stored (/etc/passwd, /etc/shadow, /etc/group), how to create and manage them, and why you should use sudo instead of logging in directly as root.

K
KaiMay 23, 2026
Software Package Management: apt, dnf, a...
DevOpsLinux

Software Package Management: apt, dnf, apk

Install, update, and remove software on Linux through the package manager. Understand the differences between distro families (apt for Debian/Ubuntu, dnf for Fedora, apk for Alpine) and tell apart updating the package list from upgrading software.

K
KaiMay 23, 2026
Disks and Capacity: df, du, lsblk, mount
DevOpsStorage

Disks and Capacity: df, du, lsblk, mount

\"The server is out of disk\" is a classic incident. This article teaches the troubleshooting workflow: df to see which filesystem is full, du to trace which directory is eating space, find for large files, plus lsblk and mount to understand storage devices.

K
KaiMay 23, 2026
Compress and Decompress: tar, gzip, zip
DevOpsLinux

Compress and Decompress: tar, gzip, zip

Bundle many files into one and compress them for backups or moving data. Understand the difference between archiving (tar) and compressing (gzip), memorize the confusing tar flags, and know when to use tar.gz vs zip.

K
KaiMay 23, 2026