Timedora
Free Practice Quiz Question List

3 DNS Configuration and Troubleshooting Online Quiz Questions

Use this free practice quiz with 20 questions to review 3 DNS Configuration and Troubleshooting, test your knowledge, and prepare for your next test or exam.

20 questions
01
True or false
1 point

True or false: DNS commonly uses UDP port 53 and can also use TCP.

  1. A

    True

  2. B

    False

02
Choose one
1 point

Which statement correctly describes the DNS record types A and AAAA?

  1. A

    A maps to IPv6 and AAAA maps to IPv4.

  2. B

    A maps to IPv4 and AAAA maps to IPv6.

  3. C

    Both A and AAAA identify mail servers.

  4. D

    Both A and AAAA map addresses to names in reverse-lookup zones.

03
Choose one
1 point

Which role does a PTR record serve in DNS?

  1. A

    It maps a host name to an IPv4 address.

  2. B

    It identifies a mail server and its preference.

  3. C

    It maps an address to a name in a reverse-lookup zone.

  4. D

    It marks the start of a zone and includes timing values.

04
Written response
1 point

In the example zone file, what SOA serial number is shown?

05
Choose one
1 point

A domain needs DNS data identifying its mail servers and their preference. Which record type should be configured?

  1. A

    It marks the start of a zone and specifies its timing values.

  2. B

    It identifies a domain's mail servers and includes a preference value.

  3. C

    It maps an address to a name in a reverse-lookup zone.

  4. D

    It gives a name an alias of another canonical name.

06
True or false
1 point

True or false: nslookup necessarily follows the same local resolution path as ordinary applications.

  1. A

    True

  2. B

    False

07
Choose all
1 point

A client resolves web.example.com but fails to resolve the short name web. Select all useful next checks before changing DNS records.

  1. A

    Inspect the client's DNS suffix settings or suffix search list.

  2. B

    Assume the fully qualified name's record is missing and recreate it.

  3. C

    Check which fully qualified name the short-name query is formed into.

  4. D

    Treat the difference as proof that the authoritative server is unreachable.

08
Fill in the blank
1 point

To delegate a subdomain, the parent zone publishes naming the child's authoritative servers. The child zone must contain its own .

09
Written response
1 point

In a DNS response, which two-letter flag indicates that the answer is authoritative?

10
Choose one
1 point

A DNS query returns NXDOMAIN. What does this response indicate according to the server that replied?

  1. A

    The name exists, but the requested record type is absent.

  2. B

    The server could not complete the lookup.

  3. C

    The queried name does not exist according to the responding server.

  4. D

    The response is authoritative and contains the requested data.

11
Written response
1 point

What role does a CNAME record serve for a DNS name?

12
Choose all
1 point

A recursive resolver returns an unexpected or stale DNS answer. Select all checks supported by standard troubleshooting practice.

  1. A

    Query the authoritative server directly and compare its answer with the recursive resolver's.

  2. B

    Change the record again immediately without checking the authoritative answer.

  3. C

    If the authoritative answer is correct, consider cached data and its TTL.

  4. D

    Treat the discrepancy alone as proof that the child zone is not loaded.

13
Open ended
1 point

A parent zone delegates dept.example.com to a server, but direct queries to that server do not return authoritative answers for the child. Explain what this problem is called and what checks would help diagnose and correct it.

14
Choose one
1 point

You need example.com to resolve directly to the web server’s IP address. Which configuration follows the stated DNS record rules for a zone apex?

  1. A

    Create a CNAME at the apex and keep the SOA record there.

  2. B

    Use A and/or AAAA records at the apex instead of a CNAME.

  3. C

    Create an MX record at the apex pointing to the web server.

  4. D

    Use a PTR record to map the apex to its IP address.

15
True or false
1 point

A client resolves web.example.com but fails to resolve web. Checking the client’s DNS suffix settings is a reasonable next step before changing the zone.

  1. A

    True

  2. B

    False

16
Choose one
1 point

A DNS query returns NXDOMAIN. Which interpretation best matches that response?

  1. A

    The server could not complete the lookup; inspect logs and upstream resolution.

  2. B

    The name exists, but the requested record type is absent.

  3. C

    The responding server says the queried name does not exist.

  4. D

    The client received an authoritative answer with the AA flag.

17
Written response
1 point

Which DNS record type identifies the mail servers for a domain and includes a preference value?

18
Choose one
1 point

You edit a DNS zone, but the updated data is not being served by its authoritative server. Which action is part of applying the change correctly?

  1. A

    Update the SOA serial number, then reload or publish the zone.

  2. B

    Change the MX preference value and wait for the resolver cache to clear.

  3. C

    Remove the SOA record and query the parent zone for the new data.

  4. D

    Change the zone’s NS records to the client’s configured resolver.

19
Choose one
1 point

You run dig @192.0.2.53 example.com SOA +norecurse to check whether the server is authoritative for the zone. Which response detail supports that conclusion?

  1. A

    The server should return a referral, identified by the RA flag.

  2. B

    An authoritative answer should include the AA flag.

  3. C

    The server should return NXDOMAIN because recursion is disabled.

  4. D

    The response should include the AD flag to show the server is authoritative.

20
Fill in the blank
1 point

In a BIND zone file, a name written as ns1.example.com. ends with a dot. The dot indicates that the name is .