Cisco 837 - how to set up DNS proxy? Bug in IOS?

Hi,

I'd like to configure my 837 as a DNS proxy. The 837 is 192.168.1.1, and I'm using it as a DHCP server.

What I'd trying to achieve is this: I'd like my LAN devices to get their addresses via DHCP, and for the router to act as the DNS server, forwarding requests to the actual DNS servers provided by my ISP. So an IPCONFIG /ALL on a client would show "Default Gateway 192.168.1.1" and "DNS Server 192.168.1.1".

According to release notes here

(search for "DNS Proxy") I should be able to do this, and the key requirements seem to be these two commands:

ip dns server ip name-server 1.1.1.1 2.2.2.2 3.3.3.3

HOWEVER.....

when I enter the ip name-server command, specifying my ISP's DNS server (212.104.130.9) the command never "sticks". If I enter:

conf t ip name-server 212.104.130.9 exit sh run

there is no trace of the 212.104.130.9. Buf if I instead enter:

conf t ip name-server 192.168.1.1 exit sh run

the command is there. So it lets me enter an internal IP but not an external IP. But that defeats the object - I need to be able to specify the ISP's IP.

Somebody posted an identical question (and answer) here:

so it looks like I'm on the right lines. But could this be a bug in the IOS? I'm running 12.4(8).

Or am I going mad?...

Jim