How can you check if port forwarding is working?

[Nnyan]

So I've been back on OPNsense for while but since the move I have changed ISP's from Comcast to AT&T.  The main reason is that the Comcast gigabit service is only 1G/40mb while the AT&T service is 1G/1G.  When everyone was home that 40mb (at best) was starting to be a PITA bottleneck.  AT&T does do some things I'm not crazy about (no true bridge mode) but the ip-passthrough works well enough and I did not detect a double NAT.

My problem is that since I made the move to AT&T my PLEX server is unable to maintain it's external connection.  You basically have to port forward or UPNP to port 32400.  Back on Comcast this would work with UPNP or any port to 32400.  This could drop occasionally but it would come back up.  Now I can't get this to work for typically more then a few minutes although occasionally it will work for a few hours or more.

I was working on this being an AT&T issue except just about everyone on the AT&T forums was getting PLEX remote access to work.  Someone suggested getting static IP's to see if that helped.  It did not.  But that gave me an idea and since I still have my Unifi switch and USG I plugged them into the BGW-320 and assigned them a static IP (public) and now I have to "paths" out to the internet. 

When I connect my PLEX server to go out through the USG PLEX can maintain it's external connections.  I've tested this with some friends and it's been up solid for just over a week.  When i move it to the Cisco SG350 switch (which is where the OPNsense LAN port connects to), it will drop within a few mins or less.  Just to make sure I eliminate everything I broke out my Juniper EX3300 and took turns connecting each router to this switch and then the PLEX box and I got the same results. 

Just as an extra test for my Sanity I dusted off the PA220 and after some updates and settings tweaks I connected this to the EX3300 and the PLEX server to this and it so far has maintain remote access for almost 3 days.  I've attached the PF rule that I'm using.

If I don online port checkers whatever port I set for the port for PLEX is open on my USG IP but not the OPNsense IP.

I've tried looking through the logs but I really can't see anything that would pin point what my issue is with this.  Thank you ahead of time.

[Greelan]

Your port forward is essentially like mine, except I have an associated filter rule created rather than just specifying “Pass” in the Filter rule association box.

[Nnyan]

I was going to give that a try but I do not have the option to create a rule, just none or pass.

[Greelan]

Delete your current rule, then create a new one, this time leaving the Filter rule association box at its default setting. It should create the firewall rule and populate it in the port forward settings once the port forward is saved and applied

[Nnyan]

That worked thank you!  I still can't get the port to be unblocked.  For now I'm just going to run on my USG since that can handle my gigabit connection without IDS/IPS unlike my PA220.

[Greelan]

Very odd. I see you are using an alias for the plex internal IP - is that correct, and did you click Apply after creating the alias?

[Nnyan]

I do have an alias but I have tried it with just the IP of the plex server.