← Back to Glossary

What is DNS Flood: NXDOMAIN Flood?

by Bethany Hendricks on Glossary • October 2, 2020

This ties up the DNS server with trying to resolve and return results for invalid requests and can flood the server's cache thereby prohibiting legitimate server name resolution requests from being serviced.

Persisting DNS entries of a valid and operationally important domain and servers, from an organizational perspective, in the DNS server's cache will allow DNS queries from legitimate users to still get served even when an NXDOMAIN flood attack is ongoing.