Devices that my company builds use specific external DNS IP addresses for resolving hosts. When these devices are on our network, and we want to point those devices to other services internally, they fail to lookup the target hosts because they are going out to the external IP which has no knowledge of the internal network. Instead of having to reconfigure each of these devices, I was looking to set up the firewall to redirect DNS requests to the specified IP to an internal DNS server. So far, I have been unsuccessful in doing so.
The internal DNS address is 192.168.1.2, and the units get an address in the 192.168.1.50 - 192.168.1.250 range. I had setup an access list rule to block the outbound requests and specified a secondary DNS address in the devices, but lookups are much slower.
Is this something that is possible with the firewall? If not, is there an easy way to achieve the goal (maybe at a router level)?
Thanks in advance!