☾
Light
Home
› Users, Permissions & Security
🔐
Users, Permissions & Security
Accounts, sudo, permissions, SSH keys, certificates, SELinux and auditing.
adduser
Interactive user creation (Debian)
age
Modern file encryption
aide
File integrity checker
apparmor
Manage AppArmor mandatory access control profiles.
certbot
Obtain and renew Let’s Encrypt certificates
chage
Manage password aging
chmod
Change file or directory permissions.
chown
Change file or directory ownership (user and/or group).
chsh
Change login shell
deluser
Delete a user (Debian)
fail2ban-client
Control fail2ban
faillock
Show/reset failed-login locks
getenforce
Show SELinux mode
gpg
GNU Privacy Guard: encrypt, decrypt, sign, and verify files.
groupadd
Create a group
groupdel
Delete a group
lynis
Security auditing tool
newgrp
Switch primary group
openssl
Cryptography toolkit — TLS testing, key/certificate generation, and data encoding.
openssl advanced
Advanced OpenSSL: TLS debugging, certificate inspection, and PKI operations.
openssl req
Create CSRs and certificates
openssl s_client
Test TLS connections
openssl x509
Inspect certificates
pass
Standard Unix password manager
passwd
Change or set a user account password.
pwck
Verify /etc/passwd
restorecon
Restore SELinux file contexts
selinux
Manage SELinux mandatory access control policies.
semanage
Manage SELinux policy
setenforce
Switch SELinux between enforcing and permissive
ssh-add
Add keys to the SSH agent
ssh-copy-id
Install your public key on a server
ssh-keygen
Generate, inspect, and manage SSH public/private key pairs.
ssh-keyscan
Collect SSH host keys
su
Switch user
sudo
Run commands as another user (usually root)
ufw allow
Open a firewall port (ufw)
umask
Set default permissions mask for newly created files and directories.
useradd
Create a new user account on the Linux system.
userdel
Delete a user account
usermod
Modify a user account
visudo
Safely edit sudoers