TMG Route Rule

[deano]

We have a guest wireless network that has DNS entries added through DHCP for OPENDNS. This has been working fine with no issues but has now decided to stop. Upon speaking to some people, they have said that issue could be that the request through TMG is a hairpin. Basically a user on the wireless requests the in house exchange owa, through an external DNS, then back in through TMG.

 

To combat the issue, i need to create a rule with Network Rules that basically says that any request for the external address for OWA to go to an internal address and not to the external one. I'm a little stuck as to where to start or what to Google. Anybody shed some light please

[SYNACK]

You should look at using split DNS instead that way the internal and external address is the same. Iase of setting up internal DNS to be authorative for your webmail address so that it gives the internal IP instead of the external one.

[deano]

Thank you for your reply. Our Guest uses an external DNS (OpenDNS) is does not use our internal DNS structure. Will it still be best to use the split dns structure?

[SYNACK]

I would, you could even setup a second DNS server zone just to handle the guest VLANs with a fowarder to openDNS. This would speed up the lookup locally and still alow you to redirect internal services.