Connecting Ubuntu to Fortinet VPN Client: A Step-by-Step Guide

As an IT professional, setting up virtual private networks (VPNs) is essential to ensure secure remote access to company resources. In this tutorial, we'll explore how to connect an Ubuntu machine to a Fortinet VPN client.

In our example, the IP address of the Ubuntu machine is `e.f.g.h`. We have configured the `/etc/ipsec.d/nf` file with the following connection details:

```

conn icms

Where 'icms' is the name of the connection, and 'a.b.c.d' is standing in for the public IP of the FortiGate.

```

To establish a connection to the Fortinet VPN server, we'll use OpenSwan, an open-source implementation of the Internet Key Exchange (IKE) protocol. We'll also explore some common issues that may arise during the connection process.

After configuring the connection settings, we initiated an aggressive mode connection, but encountered several errors. The `iplsc` log showed:

```

002 'icms' #1: initiating Aggressive Mode #1, connection 'icms'

003 'icms' #1: received Vendor ID payload method set to=115

003 'icms' #1: received Vendor ID payload

003 'icms' #1: ignoring unknown Vendor ID payload

002 'icms' #1: Aggressive mode peer ID is ID_IPV4_ADDR: 'a.b.c.d'

003 'icms' #1: no suitable connection for peer 'a.b.c.d'

003 'icms' #1: initial Aggressive Mode packet claiming to be from a.b.c.d on a.b.c.d but no connection has been authorized

018 'icms' #1: STATE_AGGR_I1: INVALID_ID_INFORMATION

002 'icms' #1: sending notification INVALID_ID_INFORMATION to a.b.c.d:500

```

To troubleshoot these issues, we can analyze the log output and adjust our configuration settings accordingly. Since the VPN connection is unsupported by FortiGate, we may need to experiment with different settings and configurations until we achieve a successful connection.

In this article, we'll continue to explore common issues that arise during the Ubuntu-Fortinet VPN connection process and provide solutions to overcome these challenges. Stay tuned for more updates on this topic!

Ubuntu fortinet vpn client