Soru

Zorluk: OrtaDNS Infrastructure and Record Types

A network engineer is configuring DNS infrastructure to support an enterprise Voice over IP (VoIP) deployment. Automatic phone provisioning requires locating the Session Initiation Protocol (SIP) service and subsequently resolving the designated server hostname to its assigned IPv4 address. The engineer executes the following diagnostic query:

$ dig _sip._tcp.voip.net.corp SRV +short
10 60 5061 pbx-01.voip.net.corp.

Based on this output and deployment requirement, which TWO of the following DNS record types are required for successful service discovery and host reachability?

  1. SRV record to specify the service location, port 5061, and target hostname pbx-01.voip.net.corpCevap
  2. A record to resolve the target hostname pbx-01.voip.net.corp to its 32-bit IPv4 addressCevap
  3. C
    CNAME record to create an alias redirecting IP traffic directly to TCP port 5061
  4. D
    PTR record to handle forward service port mapping over UDP port 53
  5. E
    MX record to manage session negotiation protocols on TCP port 25

Cevap

The SRV record and A record are both required to achieve full service discovery and hostname resolution.
VoIP clients rely on SRV records to discover the service port and target server hostname, and subsequently rely on an A record to resolve that target hostname to its corresponding IPv4 address.

Adım Adım Çözüm

1
Analyze the service discovery query requirement
The query requires discovering the protocol, port, and hostname associated with the SIP VoIP service.
SRV records are designed specifically to publish service location parameters, including priority, weight, port (5061), and target hostname.
2
Identify the hostname resolution requirement
The SRV query returns the target domain name pbx-01.voip.net.corp.
Network clients require a standard A record to map this returned canonical hostname to a usable 32-bit IPv4 address for IP routing.

Anahtar Kavram

DNS SRV and A record pairing for network service auto-discovery
Bu soruyu puanla