In this scenario I would like to allow SMTP traffic to my internet provider so that an application in my test environment is able to send notification messages. In this environment I use pfSense.
For this to work, you have to create a port forwarding rule on the LAN interface forwarding traffic to any IP with port 587.
Open the pfSense interace and go to Firewall rules:
Then create a new rule as follows:
Make sure you use the right (internal) IP address of the server which is sending the emails.
Thank you for this solution. It absolutely worked.
Thank you! Glad to hear that!