A network technician receives reports that workstations on a local subnet are unable to access an internal intranet web server using its hostname `intranet.corp.local`, though connecting directly via IP address works properly. When executing `dig intranet.corp.local` from a workstation, the utility outputs `;; QUESTION SECTION: ;intranet.corp.local. IN A` followed by `;; AUTHORITY SECTION: corp.local. 3600 IN SOA ns1.corp.local. admin.corp.local. (...)` and zero answers in the `ANSWER SECTION`. Which of the following potential root causes and verification steps are valid for troubleshooting this issue? (Select TWO.)
- An A record for intranet.corp.local is missing or incorrectly named on the authoritative DNS server.Cevap
- BQuerying the local client DNS resolver cache using host-level utilities like dig returns authoritative server answers.
- COutbound TCP port 53 traffic is blocked by a network firewall, preventing name resolution response payloads.
- Using an authoritative lookup tool to query the primary name server directly will confirm whether the record exists on the zone file.Cevap
Cevap
The valid root cause is that the requested host record is missing or misspelled in the authoritative zone file, and a valid troubleshooting step is to query the authoritative name server directly to confirm record presence.
Receiving an SOA record in the AUTHORITY section without records in the ANSWER section indicates that the DNS server is authoritative for the domain zone, but no A/AAAA entry exists for the queried hostname. Directly querying the primary DNS server specified in the SOA record allows an administrator to inspect the authoritative record status without cached interference.
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DNS Lookup Output Interpretation & Record Verification