Ensure DNS Server is not enabled

Information

The Domain Name System (DNS) is a hierarchical naming system that maps names to IP addresses for computers, services and other resources connected to a network.

Solution

Run one of the following commands to disable named :
# chkconfig named off
# systemctl disable named
# update-rc.d named disable

See Also

https://www.cisco.com/c/en/us/td/docs/security/firepower/623/configuration/guide/fpmc-config-guide-v623.html