Ace Your EC0-350 Certified Ethical Hacker Exam

The zone transfer is the method a secondary DNS server uses to update its information from the primary DNS server. DNS servers within a domain are organized using a master-slave method where the slaves get updated DNS information from the master DNS. One should configure the master DNS server to allow zone transfers only from secondary (slave) DNS servers but this is often not implemented. By connecting to a specific DNS server and successfully issuing the ls –d domain-name > file-name you have initiated a zone transfer.

Explanations: %windir%\\system32\\drivers\\etc\\services is the correct place to look for this information.

Understanding DNS is critical to meeting the requirements of the CEH. When the serial number that is within the SOA record of the primary server is higher than the Serial number within the SOA record of the secondary DNS server, a zone transfer will take place.

Explanations:

A is not a correct answer as it is never recommended to use a DNS server for any other application. Hardening of the DNS servers makes them less vulnerable to attack. It is recommended to split internal and external DNS servers (called split-horizon operation). Zone transfers should only be accepted from authorized DNS servers.

By having DNS servers on different subnets, you may prevent both from going down, even if one of your networks goes down.