Question 1,170 of 1,819
Network Services and SecurityhardTroubleshootingObjective-mapped

CCNA Network Services and Security Practice Question

This 200-301 practice question tests your understanding of network services and security. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.

Exhibit

R1# show running-config | section ip domain
ip domain lookup
ip name-server 203.0.113.1
ip domain name example.com
!
R1# show ip dns server
DNS server: 203.0.113.1
Default domain: example.com

R1# nslookup ServerA
Server:   203.0.113.1
Address 1: 203.0.113.1

Name:      ServerA.example.com
Address 1: 203.0.113.10

R1# dig ServerA
; <<>> DiG 9.8.3 <<>> ServerA
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 1234
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;ServerA.            IN    A

;; Query time: 10 msec
;; SERVER: 203.0.113.1#53(203.0.113.1)
;; WHEN: Thu Jan 18 12:00:00 2024
;; MSG SIZE  rcvd: 28

R1# ping ServerA
Translating "ServerA"...domain server (203.0.113.1)
% Unrecognized host or address, or protocol not running.

You are connected to R1. The network uses DNS to resolve hostnames for remote device management. Currently, R1 cannot resolve the hostname 'ServerA' via DNS. Using the nslookup and dig commands, you have gathered the following outputs:

nslookup ServerA Server: 203.0.113.1 Address: 203.0.113.1#53

Name: ServerA.example.com Address: 203.0.113.10

dig ServerA ... ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: ... ...

The show running-config command shows that 'ip domain-lookup' is enabled, the name-server is 203.0.113.1, and no static host entries are configured. Diagnose and fix the DNS resolution failure. Ensure that R1 can successfully resolve 'ServerA' to its intended IP address 198.51.100.10.

Question 1hardTroubleshooting
Read the full DNS explanation →

Exhibit

R1# show running-config | section ip domain
ip domain lookup
ip name-server 203.0.113.1
ip domain name example.com
!
R1# show ip dns server
DNS server: 203.0.113.1
Default domain: example.com

R1# nslookup ServerA
Server:   203.0.113.1
Address 1: 203.0.113.1

Name:      ServerA.example.com
Address 1: 203.0.113.10

R1# dig ServerA
; <<>> DiG 9.8.3 <<>> ServerA
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 1234
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;ServerA.            IN    A

;; Query time: 10 msec
;; SERVER: 203.0.113.1#53(203.0.113.1)
;; WHEN: Thu Jan 18 12:00:00 2024
;; MSG SIZE  rcvd: 28

R1# ping ServerA
Translating "ServerA"...domain server (203.0.113.1)
% Unrecognized host or address, or protocol not running.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

Add a static host entry: 'ip host ServerA 198.51.100.10'

The nslookup output misleadingly shows a response with IP 203.0.113.10, but the dig output reveals NXDOMAIN, indicating the DNS server has no valid A record for ServerA. The returned address is a default domain record that does not point to the correct device. Since the external DNS server cannot be modified, the quickest and valid fix is to add a static host entry on R1 using 'ip host ServerA 198.51.100.10', which overrides DNS and ensures correct resolution. Option B is incorrect because changing to 8.8.8.8 would still depend on a remote server having the correct record, which is not guaranteed. Option C is wrong because 'ip domain-lookup' is already enabled, so disabling/enabling it has no effect. Option D is wrong because modifying the domain name only affects how FQDN is built but does not fix the missing A record or wrong IP issue.

Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • Add a static host entry: 'ip host ServerA 198.51.100.10'

    Why this is correct

    Since the DNS server returns an incorrect IP for ServerA (203.0.113.10 instead of 198.51.100.10) and we cannot modify the external DNS server, creating a static host entry on R1 overrides DNS and provides the correct IP. This is a common workaround when DNS is misconfigured or unavailable.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Change the DNS server to 8.8.8.8 using 'ip name-server 8.8.8.8'

    Why it's wrong here

    This is incorrect because the problem is not that the DNS server is unreachable; nslookup shows a response from 203.0.113.1. The issue is that the DNS server has a wrong A record for ServerA. Changing to 8.8.8.8 might resolve the hostname if that server has the correct record, but it is not guaranteed and does not address the root cause of the misconfigured DNS server.

  • Enable 'ip domain lookup' with 'ip domain-lookup' command

    Why it's wrong here

    This is incorrect because 'ip domain lookup' is already enabled by default on Cisco routers. The nslookup output shows that DNS queries are being sent and responses received, so the issue is not that DNS lookup is disabled.

  • Configure the correct domain name using 'ip domain-name example.com'

    Why it's wrong here

    This is incorrect because the nslookup output shows that the DNS server is returning a response for 'ServerA.example.com' with an IP, so the domain name is already being appended. The issue is not the domain name configuration but the incorrect A record on the DNS server.

Option-by-option analysis

Why each answer is right or wrong

Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 200-301 exam frequently reuses these exact scenarios with slightly different constraints.

Add a static host entry: 'ip host ServerA 198.51.100.10'Correct answer

Why this is correct

Since the DNS server returns an incorrect IP for ServerA (203.0.113.10 instead of 198.51.100.10) and we cannot modify the external DNS server, creating a static host entry on R1 overrides DNS and provides the correct IP. This is a common workaround when DNS is misconfigured or unavailable.

Change the DNS server to 8.8.8.8 using 'ip name-server 8.8.8.8'Wrong answer — click to see why

Why this is wrong here

The DNS server is reachable and responds, but with incorrect data. Simply changing the server may not fix the issue if the new server also lacks the correct record.

Why candidates choose this

Candidates often assume DNS issues are due to unreachability and try to change the server to a public one like 8.8.8.8, overlooking that the current server is responding but with wrong data.

Enable 'ip domain lookup' with 'ip domain-lookup' commandWrong answer — click to see why

Why this is wrong here

The command 'ip domain-lookup' enables DNS resolution, but it is enabled by default. The problem is the incorrect DNS record, not the feature being disabled.

Why candidates choose this

Candidates might think DNS resolution is not working because the feature is disabled, especially if they forget that it is enabled by default. However, the nslookup output confirms DNS is active.

Configure the correct domain name using 'ip domain-name example.com'Wrong answer — click to see why

Why this is wrong here

The domain name is already being used in the query (ServerA.example.com). Configuring a different domain name would change the query but not fix the incorrect record for ServerA.

Why candidates choose this

Candidates may think that the hostname is not being fully qualified, but the output shows the domain is appended. They might also confuse this with the need to set a domain name for other features like SSH.

Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”

Common exam traps

Common exam trap: answer the scenario, not the keyword

Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.

Trap categories for this question

  • Command / output trap

    This is incorrect because the problem is not that the DNS server is unreachable; nslookup shows a response from 203.0.113.1. The issue is that the DNS server has a wrong A record for ServerA. Changing to 8.8.8.8 might resolve the hostname if that server has the correct record, but it is not guaranteed and does not address the root cause of the misconfigured DNS server.

Detailed technical explanation

How to think about this question

This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.

KKey Concepts to Remember

  • Read the scenario before looking for a memorised answer.
  • Find the constraint that changes the correct option.
  • Eliminate answers that are true in general but not in this case.
  • Use explanations to understand the rule behind the answer.

TExam Day Tips

  • Underline the problem statement mentally.
  • Watch for words such as best, first, most likely and least administrative effort.
  • Review why wrong options are wrong, not only why the correct option is correct.

Key takeaway

Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Real-world example

How this comes up in practice

A practitioner preparing for the 200-301 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.

What to study next

Got this wrong? Here's your next step.

Identify which 200-301 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.

Related practice questions

Related 200-301 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Practice this exam

Start a free 200-301 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

FAQ

Questions learners often ask

What does this 200-301 question test?

Network Services and Security — This question tests Network Services and Security — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Add a static host entry: 'ip host ServerA 198.51.100.10' — The nslookup output misleadingly shows a response with IP 203.0.113.10, but the dig output reveals NXDOMAIN, indicating the DNS server has no valid A record for ServerA. The returned address is a default domain record that does not point to the correct device. Since the external DNS server cannot be modified, the quickest and valid fix is to add a static host entry on R1 using 'ip host ServerA 198.51.100.10', which overrides DNS and ensures correct resolution. Option B is incorrect because changing to 8.8.8.8 would still depend on a remote server having the correct record, which is not guaranteed. Option C is wrong because 'ip domain-lookup' is already enabled, so disabling/enabling it has no effect. Option D is wrong because modifying the domain name only affects how FQDN is built but does not fix the missing A record or wrong IP issue.

What should I do if I get this 200-301 question wrong?

Identify which 200-301 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.

What is the key concept behind this question?

Read the scenario before looking for a memorised answer.

About these practice questions

Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

Last reviewed: Jun 6, 2026

Question Discussion

Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.

Loading comments…

Sign in to join the discussion.

This 200-301 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-301 exam.