DNS and DHCP Infrastructure Flashcards

Which DHCP configuration permanently maps a specific client MAC address to a fixed IP address so the client always receives the same address?

Answer: Reservation

A DHCP reservation links a client's MAC address (or DUID for DHCPv6) to a specific IP address, ensuring consistent assignment every time.

Which DNS record type identifies the mail exchange servers responsible for accepting inbound email for a domain and their priority?

Answer: MX

MX (Mail Exchanger) records specify the hostnames of mail servers for a domain along with a priority value; lower priority numbers indicate preference.

When a configured DNS forwarder fails to respond, what does the DNS server use as a fallback to attempt resolution?

Answer: Root hints

If all forwarders fail to respond, the DNS server falls back to root hints and attempts to resolve the query iteratively starting from the root servers.

What DHCP feature allows a single DHCP server to assign addresses from multiple logical IP subnets on the same physical network segment?

Answer: Superscope

A superscope is an administrative grouping of member scopes that allows one DHCP server to service multiple logical subnets on a single physical network.

Which DNS record type allows Active Directory clients to automatically discover services such as LDAP and Kerberos by specifying both the server hostname and port?

Answer: SRV

SRV (Service) records enable service discovery by specifying the hostname, port, priority, and weight for services like LDAP (_ldap._tcp) and Kerberos (_kerberos._tcp).

In a DHCP split-scope configuration, what is the recommended address percentage split between the primary and secondary DHCP servers?

Answer: 80/20

The recommended split-scope configuration assigns 80% of addresses to the primary DHCP server and 20% to the secondary, ensuring the primary handles most requests while the secondary provides fault tolerance.