Changing DNS Server Public IP
My company is the Maintainer for at least one second level domain like example.com. The previous sysadmin created a DNS server running on a public IP address x.x.x.x which resolves "public" dns queries for that domain. Now we are migrating from one ISP to another and our public IP address will soon change in something like y.y.y.y. I think we will loose our DNS reachability. How can I avoid this? We also run a mail server inside our network and we don't want to loose mail server reachability.