Ubuntu coldfusion2025 PDFManager not working

Ian, you're almost there.

First, you say in reply to me, "No reference to ther port 5500 starting??", but note it was indeed the first line of the logging you quoted:

Jul 28, 2025 07:59:27 AM Information [Thread-24] - Enabling port 5500 to serve and receive content from remote PDFg service.

And then also the last line of all that logging:

Jul 28, 2025 08:35:44 AM Information [http-nio-8500-exec-2] - Enabling port 5500 to serve and receive content from remote PDFg service

So we're halfway home, I think. I would assert now that the problem is that the remote server can't reach that port on the cf server. I know you said you turned off defender. Let's not stop there.

1) First, did you then do the steps I proposed (for after addressing FW issues) to again try to enable and verify the remote pdf service, in the cf admin of the server doing the cfhtmltopdf? 

2) If you may say you did (or now do) that and things still don't work, see then also my final suggestion to make sure the jetty request log is still reporting a 500. It may have changed to now a 403 status code, which would be a different problem (one that's new to recent cf updates, which I can elaborate on if needed).

3) Also, let's not have you hang your hat on merely having disabled defender. Let's confirm simply if the remote pdf server CAN reach that port 5500 on the cf server. 

Go to the remote pdf server, and in the jetty request log find the request getting a 500 status code (on the pdfgservlet call from the cf server requesting a pdf). Note the ip address shown for that line (in the first couple of columns): this will be the ip address of the cf server sending the pdf request. 

Now, test if that remote pdf server (in your case, itself another cf instance on the remote machine) can reach port 5500 on the originating cf server. There are several ways to do that, from old school telnet (now disabled by default in windows) to curl (now built into windows) to powershell:

Curl thatip:5500

Or

powershell Test-NetConnection thatip -port 5500

Do any of those show a failed connection?

If so, that's why the attempt to use that as a remote pdf service fails (sadly, without ANY tracking in the logs on the cf side, and just a blank page shown the user).

4) Finally, if adding a rule in the defender firewall for port 5500 (to open it initially to all) doesn't work (along with later limiting it to access from the ip of that remote server), then it would seem you may have yet another firewall in the way, on either end. 

If the two machines aren't in the same network, that's definitely possible. For instance, if the cf machine is in your home and the remote pdf server (your other cf instance) is at work, your home router could be blocking port 5500. Or the work machine might even use a firewall that blocks OUTBOUND calls to non standard ports. (Indeed, see if you can simply access the cf admin of each machine from a browser in the other.) 

If you fix that (get the port to be accessible), don't forget to repeat the steps in my point 1, or check if you're now suffering the problem in my point 2.

Then let us know what you find. I appreciate it's frustrating and feels fiddly. As I said, the two-way communication with remote pdf services is unexpected to most, and little-documented. And many who persevere to solve it don't bother explaining how they did: they just get on with other priorities, as I'm sure you'd like to! 🙂 

I think you could be really very close to resolving this.