Articles

Contains various writings, tutorials, cheatsheets, manuals.

Operating system

• Pre OS era, necessity of operating systems
• Process as virtualisation
• File, VFS (Virtual FileSystem), filesystem abstraction
• OS security functions (uid/gid, ulimit, apparmor, selinux)
• Lightweight OS virtualisation techniques (chroot, namespace)
• Resource management (cgroup, quota)

User interfaces

• Shell/CLI/TUI and ~ environments
• GUI and ~ environments

Package and software management

• OS package management systems (apt, dnf, packman, zipper, brew, nix-env, opkg)
• Application container systems (snap, flatpak)
• Containerized systems (dockerhub images)
• Programming language oriented package managers (pip, go, cargo)

System and service management

• Init system
• • Article - Init system - systemd
• • Article - Init system - tini
• logging/journal
• coredumpctl

Networking

• OSI network model
• Interfaces/bridge, IPv4/IPv6 addressing
• Main protocols: ARP, ICMP, UDP, TCP
• DNS
• • Article - DNS - dnsmasq
• • Article - DNS - coredns
• Routing
• netfilter, firewall, conntrack, masquerade
• VPN
• VLAN
• WLAN
• DHCP
• peer to peer

Virtualisation

• 6 types of virtualisation

Cryptography

• Hashing
• Certification

Operation

• System boundaries
• Lifecycle of Systems
• System monitoring
• Backup, DRP, DRS