NSE7_EFW Security And VPN Practice Question
You are configuring an IPsec VPN tunnel between two FortiGates. Phase 2 fails to come up. What is the most likely cause?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Mismatched Phase 2 selectors
Phase 2 failure is usually due to mismatched selectors (proxy IDs) or mismatched encryption/authentication algorithms.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Mismatched Phase 2 selectors
Why this is correct
Phase 2 requires matching local and remote subnets/selectors.
- ✗
Incorrect IKE version
Why it's wrong here
IKE version is a Phase 1 negotiation parameter.
- ✗
Expired certificate
Why it's wrong here
Certificate issues typically affect Phase 1 authentication.
- ✗
Mismatched pre-shared key
Why it's wrong here
Mismatched PSK causes Phase 1 failure.
Quick reference
VPN Protocol Comparison
| Protocol | Port | Encryption | Authentication | Use Case |
|---|---|---|---|---|
| IKEv2 / IPsec | UDP 500 / 4500 | AES-256 | Certificates / PSK | Site-to-site & remote access |
| SSL / TLS VPN | TCP 443 | TLS 1.3 | Certificates / MFA | Clientless remote access |
| L2TP / IPsec | UDP 1701 | AES (IPsec) | PSK / Certificates | Legacy remote access |
| WireGuard | UDP 51820 | ChaCha20 | Public keys | Modern high-performance VPN |
| PPTP | TCP 1723 | MPPE (weak) | MS-CHAPv2 | Legacy — avoid in production |
PPTP is considered insecure. IKEv2/IPsec and SSL VPN are the current recommended options.
About these practice questions
Courseiva writes every NSE7_EFW question from scratch — 91 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official Fortinet exam blueprint
This NSE7_EFW practice question is part of Courseiva's free Fortinet certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the NSE7_EFW exam.