pix as dns forwarder

Officially, PIX is not designed to do so. But we can make it work by using following commands-

Suppose that ISPs DNS server IP is 4.2.2.2 and PIX inside interface IP is 1.1.1.1. In this case, try following commands:

static (outside,inside) udp interface 53 4.2.2.2 53

clear xlate

Now all the UDP port 53 requests, which are DNS requests, when directed to PIX's inside interface IP, PIX will redirect them to udp (53) on the ISP's DNS server.

Hope this works for you.