can't access 3CX from inside anymore

[MM1969]

I have several 3cx systems that were v18 and upgraded to v20 so they use port 5001 instead of 443. I can access all these systems from outside using the fqdn:5001. I set up split dns and it was working a few months ago from all of them. Now some of them will work and some do not. I noticed that i have newer versions of firefox on all the ones that do not work. anyone else having issues with this? version 143.04 or earlier seem to work but 144.02 and newer do not.

 

[MM1969]

it isn't the firefox version i was able to test that. if i remove the split dns programming from my firewall so the fqdn pings the public then i go to 3cxserverIP:5001/#/login and it will let me connect from inside. fqdn:5001/#/login will not connect if i have the split dns applied although it test good if i ping the fqdn from inside it returns the private 3cx ip address. it times out connecting to the fqdn

 

[VoIPTools]

As I was reading through your description of the problem, I was pretty convinced that something is not working correctly with your split DNS and I was going to recommend you do a simple ping on your FQDN. My assumption was that it would not return with the correct IP or not resolve at all. But then you mentioned that the ping test works fine.

Perhaps we need to do a trace route to see how you are getting to the FQDN. Let's make sure there isn't some strange hop in there. Also, are you doing any vlans that could be segregating some of the traffic? If you do a trace route from the 3CX server to an internal device, does it route as you expected? Let's make sure you are using an internal static IP address too?

 

[SteveITS]

were v18 and upgraded to v20 so they use port 5001 instead of 443

The default in v20 is 443...one must change the port during installation. Your statement seems backwards? Upgrading Debian in place keeps the port; if you upgraded Windows via uninstall+reinstall it's best to manually keep the same port so devices connect.

Any chance you are port forwarding WANIP:5001 to LANIP:443 and thus using the incorrect port when on a LAN device?

I use Firefox and have had no trouble connecting to servers but none are on our LAN, they're all in our data center. That shoud not matter though.

 

[MM1969]

thanks for the response guys, i use esxi 7.0 on my older systems (pfsense firewall) and nutanix (fortigate fw) on my newer ones. i just had a nutanix set up 3cx fail. I use linux mint and firefox to manage the 3cx from inside on both setups. i went in to firefox, cleared my browser history, turned off pop up blocker and it just started working. this does seem to be something in the firefox setup. i go to the same URL when it does't work it just sits there and tries to connect then fails.I will see if i can figure out exactly what fixed it with one of my other systems that still isn't working and post it here.