1721 NAT DNS Problems

[bill.brosius]

I am trying to setup my first Cisco router as a perimeter router using NAT. I am a product of the GUI age so I am using the SDM to configure the router. I went through the initial configuration wizard and set it up for NAT, but clients on the LAN are not able to get to the internet.

Using the SDM I tested the Ethernet0 (WAN) interface and the FastEthernet0 (LAN) interface. The WAN interface tested fine as the first two pages of the attached pdf show. The LAN interface failed as you can see on the last two pages of the attached pdf.

My clients are manually configred as follows:

IP:192.168.1.XXX

MASK:255.255.255.0

GATE:192.168.1.1

DNS:192.168.1.1

What more do I need to configure to allow internal traffic to get to the internet? Any help would be greatly appreciated.

[thisisshanky · Accepted solution]

Bill,

You cannot use the router as a DNS server, as the router doesnt listen on port 53 for dns request, nor does it maintain a database for DNS entries. You will have to use external dns server ip address in this case. (65.106.1.196 and 65.106.7.196) on the clients. If the clients were using DHCP, it would have been easier to make this change. Since you have set this manually, you will have to change it on every PC. Note that Cisco router can be configured as a DHCP server.

[bill.brosius]

Bugger. Not a big deal. I am going to be installing AD and DNS in stage two so all is well. Thanks for the quick reply.