What does Fast Flux DNS mean?
A fast flux DNS strategy is where a hacker or other party registers on a domain name system in deceptive ways that prevents host server IP addresses from being identified. It is a concern for security professionals because abuse of this system can help hackers to hide from law enforcement and attack systems through a network of addresses and hosts.
Techopedia explains Fast Flux DNS
In fast flux DNS, someone registers a certain number of IP addresses with a single host name, allowing them to change the associated IP addresses quickly, in order to shield the identity of the primary server. Fast flux DNS can be used for phishing, installation of malware, or all kinds of illegal site activity. In many cases, hackers are using compromised hosts to hide the origin of their activities. Fast flux DNS can be used to create botnets that operate in malicious ways with more protection from the security community. These systems are often set up in countries with lax Internet regulation where a domain name registrar may collude with the fast flux DNS system operators.