How is IP for proxy resolved


New Member
May 13, 2022
I'm experimenting with FreeSwitch on Windows and there is something (amongst others ;-)) I don't understand.
I have an outbound gateway defined and set the domain in realm and proxy.
The domain is a virtual domain (only living on the lab Broadsoft server of our provider) so it cannot be resolved using DNS and there is NO entry in the host file.
So, when I use ping from the command line it tells me the domain can not be resolved.
But when I dial an outbound number, it suddenly knows the IP address of the provider.
In Wireshark, I can see that it uses the actual IP address but it is nowhere defined in any xml.
When I put a different IP address in Proxy, it is using that one (but actually doesn't work as the IP is not correct).

How is FS doing this?
How does FS know the actual IP address for a domain that is listed nowhere?