You could add a second IP address to the system and point the DNS name at that new IP address. The server will still talk on both IPs, so none of your users will be disrupted, but you will know that anyone connecting on the old IP is not using DNS.
You could add a second IP address to the system and point the DNS name at that new IP address. The server will still talk on both IPs, so none of your users will be disrupted, but you will know that anyone connecting on the old IP is not using DNS.