To test the vulnerability, we will check your server for a DNS record it should not have. If a result is returned, then the info was pulled by your server from another DNS server and is open to this vulnerability. If no result is returned, then no further steps need to be taken, as you server is only returning DNS records that have been manually added for your configuration.
At the command prompt, type nslookup 1and1.com 126.96.36.199
Replacing the IP address above with the IP address of your server. If you do not know the IP address of your server, learn how to Find Your Server Information
The nslookup command is used in the cmd window