We just received an E-mail from our ISP (Integra) asking us to disable DNS recursion on our Cisco 2901 router. When we test it at openresolver.com
, it shows that it is open and that it is vulnerable to DNS Amplification attacks.
How can we disable DNS Recursion on our Cisco router using Cisco's IOS commands?
Please provide the commands to add to our configuration file. The current configuration file has been attached here for your examination. Please take a look at the attached .txt file.RunningConfig.txt