Solved 3CX is not working over Wi-Fi after update to V20

[gabrieli]

Hey all, I have been using 3CX for a long time, we have an on-premise server that was running pretty well with the V18, I updated the server last night to the V20 and somehow the people inside the company that want to connect to 3CX using the Wifi connection, are not able to register with the server anymore, keeps showing connecting....
3CX web and 3CX Windows app work fine in the main LAN but not in any other networks, The DNS register already exists on my DNS server, I am not sure why a server update becomes in a network issue.
As context, I am using Sonicwll as firewall, all the wifi networks across the company can reach the local server IP, however, only the wired LAN can reach the FQDN server.
I see that the server only provides through the FQDN but not for the local IP.
Any suggestion?-
We have many users who prefer to use the cellphone app instead of the Windows one.

I will appreciate any help.

 

[SteveITS]

So is split DNS set up, or no? https://www.3cx.com/docs/creating-fqdn-split-dns/

 

[gabrieli]

Yes, it is already set up.

 

[SteveITS]

all the wifi networks across the company can reach the local server IP, however, only the wired LAN can reach the FQDN server

So why can't the wireless network reach the server? Those devices need to...the FQDN is used for HTTPS/secure connections.

 

[gabrieli]

Hi Steve, the devices in the wireless network can reach the server's local IP address without a problem, however, the 3CX apps in those devices are looking just for the FQDN to get registered on the server, and the wireless network somehow can't solve the FQDN. All was working fine before the update.
The FQDN is using https:// but the local IP is using just http://

 

[SteveITS]

I see. Well, a DNS issue would be unrelated to 3CX because 3CX doesn't provide DNS. I'd connect a laptop to the wireless network and try to figure out why the FQDN isn't resolving correctly. Your description sounds like split DNS isn't working on the wireless network. [edit: or NAT reflection/hairpin, if preferred]

 

[gabrieli]

I see. Well, a DNS issue would be unrelated to 3CX because 3CX doesn't provide DNS. I'd connect a laptop to the wireless network and try to figure out why the FQDN isn't resolving correctly. Your description sounds like split DNS isn't working on the wireless network. [edit: or NAT reflection/hairpin, if preferred]

 

[gabrieli]

I solved the issue by creating a NAT Rule policy in Sonicwall, it is translating all the traffic from the FQDN to the on-premise server no matter the source.
Thanks to all for the ideas.