Cisco ASA - Guest WIFI - exchange server connectivity

[LovejitSingh1313]

Hello Guys @balaji.bandi  @Rob Ingram  

I have separate interface with separate subnet for Guest WIFI and it only has internet access. Guest WIFI is using Public DNS servers.  It is resolving to the Public IP which is mapped to internal IP of Exchange. 

Right now it is not working? Please advice how to make it working?

Thanks,

[Rob Ingram]

Please provide the configuration and the output of “show Nat detail” 

Run packet-tracer from the CLI and provide the output

[Marius Gunnerud · Accepted solution]

So, Your exchange server is being NATed to a public IP and the Guest WIFI is not able to access the server since they are being resolved to the public IP?

If this is the case, then you have two options to solve this.

1. configure a twice nat statement on the ASA that translates the destination public IP of the Exchange server to the private IP of the server for the Guest WIFI network.

example (change interface names and IP addresses as needed)

object network Exch-real-IP

 host 10.10.10.2

object network Exch-public-IP

 host 1.1.1.2

object network GuestWIFI

 subnet 20.20.20.0 255.255.255.0

nat (GuestWIFI,DMZ) source static GuestWIFI GuestWIFI destination static Exch-real-IP Exch-public-IP

2. Add the DNS key word to the end of the existing NAT statment for the Exchange server.  in this case you will also need to add an access rule allowing the Guest WIFI access to the private IP of the exchange server.