ipsec Archives - ITNotes

Networking tutorial - IT technology blog

Route-Based IPsec VPN with strongSwan and VTI on Linux: Secure Cloud-to-On-Premises Connectivity

October 19, 2026

Build a route-based IPsec VPN on Linux with strongSwan and VTI. Learn how to configure XFRM marks, automate tunnel interfaces, avoid MTU black holes, and route hybrid cloud subnets without downtime.

Networking

Configuring GRE over IPsec on Linux for Secure OSPF Dynamic Routing

October 4, 2026

Pure IPsec tunnels drop the multicast packets that dynamic routing protocols like OSPF require. This operational guide shows you how to wrap GRE in IPsec transport mode on Linux, securing branch-to-branch links while maintaining dynamic route adjacencies.

Networking

Site-to-Site VPN with StrongSwan IPsec IKEv2: A Production-Ready Linux Guide

April 18, 2026

Build a high-performance Site-to-Site VPN using StrongSwan on Linux. This guide covers IKEv2 configuration with swanctl, firewall tuning, and MSS clamping for maximum stability.