NSE7 Advanced VPN and Zero Trust Practice Question
An administrator is troubleshooting an IPsec VPN tunnel between two FortiGates. The tunnel is up, but traffic is not passing. The administrator runs 'diagnose vpn tunnel list' and sees that both phase 1 and phase 2 are up. The policy allows traffic from both sides. What should the administrator check next?
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
✓
Check the routing table for routes to the remote subnet
Since both phases are up and policies are correct, the issue is likely routing. The administrator should verify that the correct routes are pointing to the VPN interface (tunnel interface) on both sides. Without proper routes, traffic will not be forwarded into the tunnel.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Check the routing table for routes to the remote subnet
Why this is correct
Routes are needed to send traffic into the tunnel.
- ✗
Increase the phase 2 keylife
Why it's wrong here
Keylife does not affect traffic flow.
- ✗
Check the FortiGate's NTP status
Why it's wrong here
NTP is not directly related to traffic flow.
- ✗
Disable DPD
Why it's wrong here
DPD affects tunnel liveliness, but tunnel is up.
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.
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JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This NSE7 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 exam.