About This Domain
Domain 3 — Security — accounts for 18% of the LINUXPLUS certification exam. This domain evaluates your understanding of authentication methods (pam, ssh, mfa), firewall management (iptables, firewalld, nftables), os hardening and selinux/apparmor, and related concepts. Authentication, firewalls, OS hardening, and cryptography. To pass this section you need practical knowledge of how these technologies work together.
What You'll Be Tested On
- Authentication methods (PAM, SSH, MFA)
- Firewall management (iptables, firewalld, nftables)
- OS hardening and SELinux/AppArmor
- Cryptography and PKI basics
Key Technologies in This Domain
Study Strategy for Domain 3
While 18% might seem like a smaller portion, every point counts toward the passing score.
Exam Tips for Domain 3
Know SELinux modes (Enforcing, Permissive, Disabled) and how to change them.
Frequently Asked Questions
How many questions come from Domain 3?
Domain 3 (Security) makes up 18% of the LINUXPLUS exam.
What should I focus on for Domain 3?
Key topics include Security.
How should I prepare for Security questions?
Review key topics, then practice with domain-specific questions focusing on real-world scenarios.
What's the best order to study LINUXPLUS domains?
Start with highest-weighted: System Management (23%), Services and User Management (20%), Security (18%), Automation, Orchestration, and Scripting (17%), Troubleshooting (22%).
Practice Domain 3 Questions
Test your knowledge of Security with practice questions from our LINUXPLUS question bank.
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