Certmaster Explaining Network Services Flashcards
An administrator ran a command and determined that the FQDN of a client is forbes.sales.realty.com. What is the hostname of the client?
A.com
B.sales
C.forbes
D.realty
C
A fully qualified domain name (FQDN) consists of the hostname and a domain suffix. In this domain, forbes is the hostname and the domain suffix is sales.realty.com.
A fully qualified domain name (FQDN) consists of the hostname and a domain suffix. In this domain, the suffix .com is the top-level domain.
An administrator configures a new mail server to meet the organization’s goals. Which record lists the IP addresses or names of servers that can send email from a particular domain and combats the sending of spam?
A.SPF
B.SRV
C.TXT
D.MX
A
A Sender Policy Framework (SPF) is a TXT-based record that lists the IP addresses or names of servers that can send email from a particular domain and combats the sending of spam.
A Service (SRV) record contains the service name and port for a particular application. SRV records often locate VoIP or media servers.
A text record (TXT) stores any free-form text that may support other network services. A single domain name may have many TXT records.
A Mail Exchange (MX) record identifies an email server for the domain. The host identified in an MX record must have an associated A or AAAA record. A MX record must not point to a CNAME record.
An organization has multiple subnets but is only using one DHCP server. How is this possible? (Select all that apply.)
A.Stateless address autoconfiguration
B.Default gateway
C.DHCP relay
D.UDP forwarding
C, D
Administrators can configure a DHCP relay agent to provide forwarding of DHCP traffic between subnets to avoid provisioning and configuring DHCP servers on every subnet.
UDP forwarding is a more general application of a DHCP relay, but UDP forwarding forwards DHCP, the Network Time Protocol (NTP), and other broadcast-based applications.
In IPv6, the Stateless Address Autoconfiguration (SLAAC) process can locate routers (default gateways) and generate a host address with a suitable network prefix automatically.
A default gateway is the IP address of the router that allows devices on one subnet to communicate with devices on other subnets.
A user has typed www.network.com into a web browser. The domain name server cannot resolve the name, so it is querying other name servers to try to find it. What kind of lookup is the domain name server performing?
A.Iterative
B.Recursive
C.Start of authority
D.Resource record
B
In this scenario, a recursive lookup means that the server queries other name servers until it finds the requested record or times out.
In an iterative lookup, a name server responds to a query with either the requested record or the address of a name server at a lower level in the hierarchy that is authoritative for the namespace.
The Start of Authority (SOA) record identifies the primary authoritative name server that maintains complete resource records for a zone.
Resource records allow a DNS name server to resolve queries for names and services hosted in the domain into IP addresses.
An organization is using IPv4 addresses. Which of the following records will resolve a hostname to the IP address?
A.A
B.AAAA
C.CNAME
D.Alias
A
Administrators use an address (A) record in the domain name system to resolve a hostname to an IPv4 address using the UDP transport protocol over port 53 by default.
Administrators use an AAAA record in the domain name system to resolve a hostname to an IPv6 address. Due to the large address sizes of IPv6, AAAA records can exceed the maximum UDP packet size.
A Canonical Name (CNAME), or alias record, configures an alias for an existing address record (A or AAAA). An administrator can redirect an alias to a completely different host if needed.
An alias record, or Canonical Name (CNAME) record, configures an alias for an existing address record (A or AAAA).
ICANN is a non-profit organization that’s dedicated to keeping the Internet secure. What does ICANN manage? (Select all that apply.)
A.Country codes
B.Generic TLDs
C.FQDNs
D.DNS
B, D
ICANN (Internet Corporation for Assigned Names and Numbers) manages the generic TLDs (top level domains) such as .com, .org, .net, .info, and .biz.
ICANN manages the Domain Name System (DNS) which is a global hierarchy of distributed name server databases that contain information on domains and hosts within those domains.
Organizations appointed by the relevant government generally manage country codes such as .uk, .ca, and .de.
Organizations must register a domain name with a registrar to ensure that it is unique, but the organization that registered the domain name manages its FQDNs (fully qualified domain names).
