M-DIFN -E- [domain] All nameservers on the same network

The problem explanation:

This means that the name servers provided by your service provider are located in the same network ranges. The verification procedure can not determine this with complete certainty, but it is true if:

1. Two name servers are indifferent /24 address ranges or if
2. The traceroute leading to name servers are different.

Solution of this problem:

The domain name is set up in name servers that are located on a separate network. It is common that two or more organizations mutually subscribe to each other for a secondary name server.