Something strange happens with DNS server when I use a VPN client
Hello everybody,
I have a Fortigate F60 device (v 7.2.10).
this Fortigate is implementing a conditional DNS for the Wi-Fi interface.
For some internal domain, I registered some DNS records:
192.168.1.1 is the router address.
Normally, everithing works, fine. If I try to ping one of the registered names (for example vpn.xxx.com):
  
10.1.0.1 replies to the echo request. 10.1.0.1 is the Fortigate address.
These are my network settings:
 
So far, so good. Now I try to connect via Cisco Secure Client to a VPN.
Regarding network settings, nothing has changed. My address is the same, Router address is the same, DNS address is the same. The interface is the same, so, if I ping the same address as before, I expect 10.1.0.1 to answer (as before), but now:
 79.9.x.x is replying. Who is 79.9.x.x? Is the Fortigate WAN interface:
And the domain vpn.xxxx.com, if I put it into the browser, is not reacheable anymore, because I think DNS is not functioning correctly. What am I missing?
Thank you for your support!