OpenVPN diagnostics

For both site-to-site and remote user scenarios, when things are not working as expected, we can try using some valuable tools offered by OPNsense to find possible issues. Let's look at some examples.

OpenVPN is connected but the traffic is not reaching the tunnel's destinations

I have tried to list the more common issues related to OpenVPN troubleshooting based on my personal experience here:

• The first step is to check your firewall rules and look for packets that have been blocked. Especially check the OpenVPN firewall rules and check all necessary rules have been created.
• On the client side, it can happen that the operating system is not creating the proper routes. This issue can be related to the user's permissions or some local network problem while creating the tunnel routes. Another common cause is conflicting routes (with existing interfaces or even with an IPsec tunnel).
• Always check the log file on both sides (server...