FortiGate IPsec Site‑to‑Site VPN (IKEv2) — Full CLI Setup, Verification, and Troubleshooting Guide

Introduction

IPsec site‑to‑site VPNs remain one of the most common ways to securely connect branch offices, data centers, and partner networks over the public Internet. On FortiGate, you can build these tunnels quickly via the VPN Wizard, but CLI configuration is often preferred in production for repeatability, change control, and automation. FortiOS uses IKE negotiations (Phase 1) to establish a secure control channel and then builds data‑plane IPsec SAs (Phase 2) for protected traffic. [docs.fortinet.com], [docs.fortinet.com], [community….rtinet.com]

This post focuses on a route‑based (interface‑mode) IPsec tunnel using IKEv2 and shows all key steps + commands, followed by verification and SOC‑friendly troubleshooting.

Browse to my public Blog below for full detailed tutorial.

[embed]FortiGate IPsec Site‑to‑Site VPN (IKEv2) - Full CLI Setup, Verification, and Troubleshooting Guide… This step‑by‑step guide walks through configuring a route‑based IPsec site‑to‑site tunnel on FortiGate using FortiOS…app.cyberhawkthreatintel.com