A network technician is testing connectivity on a workstation that fails to load external websites. The technician executes `nslookup portal.vendor.com` in the command prompt and receives the following output:
text
C:\> nslookup portal.vendor.com
DNS request timed out.
timeout was 2 seconds.
Server: UnKnown
Address: 192.168.1.50
*** Request to UnKnown timed out
Which of the following is the most likely reason for this DNS resolution failure?
- The local workstation cannot reach or receive a response from the configured DNS server at 192.168.1.50.Cevap
- BThe domain name portal.vendor.com lacks a valid IPv6 AAAA record in its authoritative zone file.
- CThe host resolver incorrectly initiated the DNS query over TCP port 80 instead of standard HTTP.
- DThe client resolver misinterpreted an authoritative server response as a non-authoritative cache entry.
Cevap
The local workstation cannot reach or receive a response from the configured DNS server at 192.168.1.50.
The correct option correctly identifies that a request timeout in `nslookup` occurs when the client sends a query to the designated DNS server (192.168.1.50) but receives no reply before the timer expires. This typically points to an unreachable DNS server, network path interruption, or blocked port 53 traffic.
Adım Adım Çözüm
Anahtar Kavram
DNS Timeout vs. Resolution Error Diagnosis