Linux
Security
10 guides
Linux Security Guides
SSH, permissions, hardening Browse 10 linux security tutorials with step-by-step instructions.
Start here
Popular linux security how-to guides — good first reads in this topic.
Check failed SSH login attempts on Linux
See who is hammering SSH and whether your keys are enough.
Read how-to
sudo vs root: best practice
Practical Linux guide: sudo vs root: best practice without the usual guesswork.
Read how-to
Harden SSH server on Linux
Lock down SSH without locking yourself out — test every change in a second session.
Read how-to
Linux file permissions: chmod and chown
Read and fix permission denied errors without chmod 777 everything like a maniac.
Read how-to
All Security guides
10 step-by-step tutorials for Linux.
Check failed SSH login attempts on Linux
See who is hammering SSH and whether your keys are enough.
Read guide
sudo vs root: best practice
Practical Linux guide: sudo vs root: best practice without the usual guesswork.
Read guide
Harden SSH server on Linux
Lock down SSH without locking yourself out — test every change in a second session.
Read guide
Linux file permissions: chmod and chown
Read and fix permission denied errors without chmod 777 everything like a maniac.
Read guide
SSH key-based authentication on Linux
Replace password-only SSH with keys — generate, install, test, then harden once you know you will not lock yourself out.
Read guide
Generate an Ed25519 SSH key on Linux
Better than old RSA keys for new Linux servers and Git access.
Read guide
AppArmor vs SELinux overview
Practical Linux guide: appArmor vs SELinux overview without the usual guesswork.
Read guide
Audit installed packages for security
Practical Linux guide: audit installed packages for security without the usual guesswork.
Read guide
Encrypt home directory (eCryptfs/fscrypt)
Practical Linux guide: encrypt home directory (eCryptfs/fscrypt) without the usual guesswork.
Read guide
Fail2ban basics for SSH
Automatically block IPs hammering SSH — simple jail config for small servers.
Read guide
More Linux topics
Explore other guide categories on Linux.
Install & setup
Distro installs, dual-boot, LUKS (12)
Updates
APT, upgrades, package holds (8)
Networking
Static IP, firewall, VPN (14)
Performance
systemd, logs, load, swap (11)
Backups
rsync, restic, snapshots (7)
Storage
mounts, fstab, LVM (7)
Apps & tools
Docker, LAMP, scripting (10)
Troubleshooting
GRUB, boot recovery, services (8)
Admin
Users, certs, mail relay (7)