Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
Which statement best describes why engineers often compare 'works by IP' versus 'works by name' during troubleshooting?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
Because it helps distinguish IP-path problems from DNS name-resolution problems.
This is correct because the comparison narrows the likely fault domain quickly.
B
Distractor review
Because hostnames can be routed without IP addresses.
This is wrong because name-based access still depends on IP addressing.
C
Distractor review
Because DNS replaces the need for routing tables.
This is wrong because DNS and routing solve different problems.
D
Distractor review
Because named access requires PPP on the host.
This is wrong because PPP is unrelated to hostname resolution in this context.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is assuming that hostnames can be routed without IP addresses or that DNS replaces routing functions. This misconception leads candidates to select options suggesting name-based routing or that DNS eliminates the need for routing tables. In reality, DNS only translates names to IP addresses, and routing protocols like OSPF or EIGRP handle packet forwarding. Misunderstanding this separation causes confusion during troubleshooting and exam questions, resulting in incorrect answers that overlook the layered nature of network communication.
Technical deep dive
How to think about this question
Troubleshooting network connectivity often involves distinguishing between IP-level reachability and name resolution. The core concept behind comparing "works by IP" versus "works by name" is to isolate whether the problem lies in the IP routing path or in the DNS name resolution process. IP communication relies on routing tables and protocols like OSPF or EIGRP to forward packets, while DNS translates human-readable hostnames into IP addresses. When a device can ping an IP address but not a hostname, it indicates that the routing infrastructure is functioning but DNS services may be failing. The decision process during troubleshooting uses this comparison as a quick diagnostic step. If connectivity works by IP address but fails by hostname, the engineer can focus on DNS configuration, such as verifying DNS server IPs, checking DNS forwarding, or ensuring the DNS service is operational. Conversely, if connectivity fails by IP, the problem likely involves routing, ACLs, or subnetting issues. This method efficiently narrows down the fault domain, saving time and effort in complex network environments. A common exam trap is confusing name resolution with routing capabilities. Some candidates mistakenly believe hostnames can be routed directly or that DNS replaces routing tables, which is incorrect. DNS only resolves names to IP addresses; actual packet forwarding depends on routing protocols and routing tables. In practical Cisco networks, understanding this distinction prevents misdiagnosis and ensures that troubleshooting steps target the correct layer of the network stack.
KKey Concepts to Remember
- Engineers compare connectivity by IP address versus hostname to isolate whether the problem lies in IP routing or DNS name resolution.
- Successful communication by IP address confirms that routing protocols and routing tables are functioning correctly in the network.
- Failure to communicate by hostname despite IP connectivity indicates a DNS resolution issue rather than a routing problem.
- DNS translates human-readable hostnames into IP addresses but does not participate in packet forwarding or routing decisions.
- Routing protocols like OSPF and EIGRP determine the path packets take based on IP addresses, independent of DNS.
- Troubleshooting by separating IP path verification from name resolution narrows the fault domain and speeds problem resolution.
- Misunderstanding that hostnames can be routed directly or that DNS replaces routing tables leads to common exam mistakes.
- Cisco network troubleshooting best practices prioritize verifying IP reachability before diagnosing DNS or application-layer issues.
TExam Day Tips
- 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.
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.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
Engineers compare connectivity by IP address versus hostname to isolate whether the problem lies in IP routing or DNS name resolution.
What is the correct answer to this question?
The correct answer is: Because it helps distinguish IP-path problems from DNS name-resolution problems. — Engineers compare those two tests because the difference helps separate raw IP reachability from name-resolution problems. In practical terms, if access works by IP but fails by name, the path probably exists and the fault is more likely in DNS. That comparison quickly narrows the problem space. This is one of the most practical troubleshooting shortcuts in user-facing network support.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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