207.2 Create and Maintain DNS Zones (weight: 3) LPIC-2 Practice Questions (Page 4)

Questions 16–20

1. 16expert · hard

   A company has delegated sub.example.com to an external DNS provider. The external provider's name servers are ns1.external.net and ns2.external.net. The parent zone currently has: sub IN NS ns1.external.net. sub IN NS ns2.external.net. Users report intermittent resolution failures for names in sub.example.com. What is the most likely cause?

   • AThe NS records are incorrect.
   • BThe SOA serial is too low.
   • CThe glue records are missing.
   • DThe external provider's name servers are not reachable from all locations.
   Reveal Solution Discussion Select an answer first
2. 17foundation · easy

   Which command is used to check a DNS zone file for syntax errors before loading it?

   • Anamed-checkzone
   • Brndc status
   • Cdig
   • Dnamed-checkconf
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4. 18expert · hard

   A company runs a primary DNS server and a secondary. The secondary has been down for 6 days. The SOA record has refresh=3600, retry=600, expire=604800, and negative TTL=300. The administrator needs to make a critical change to the zone. What is the best course of action?

   • AMake the change, but do not increment the serial to avoid confusing the secondary.
   • BDelete the secondary's zone file and reconfigure it from scratch.
   • CWait for the secondary to come back online before making the change.
   • DMake the change, increment the serial, and reload the zone; the secondary will sync when it returns.
   Reveal Solution Discussion Select an answer first
5. 19foundation · easy

   Which DNS query type is used to transfer the entire zone file from a primary to a secondary name server?

   • ANS
   • BIXFR
   • CSOA
   • DAXFR
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6. 20expert · medium

   A primary DNS server for example.com has been running for months. The administrator notices that the zone file's serial number is 2024010101 and the SOA refresh is 3600. After making a change and incrementing the serial to 2024010102, the secondary server does not update. What is the most likely cause?

   • AThe secondary's refresh interval has not elapsed yet.
   • BThe primary's allow-transfer list is empty.
   • CThe secondary's zone file is read-only.
   • DThe serial number is not in the correct format.
   Reveal Solution Discussion Select an answer first