Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
Why is disabling unused services on network devices considered a sound security practice?
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 reduces unnecessary attack surface and exposure on the device.
This is correct because disabling unneeded services removes avoidable risk.
B
Distractor review
Because it automatically improves routing convergence.
This is wrong because service hardening is not the same thing as routing optimization.
C
Distractor review
Because it guarantees the device cannot be misconfigured.
This is wrong because hardening helps, but it does not eliminate all possible mistakes.
D
Distractor review
Because it converts the device into a controller.
This is wrong because disabling services does not change the device role in that way.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is selecting answers that link disabling unused services to network performance improvements or device role changes. For instance, some candidates mistakenly think that turning off unused services speeds up routing protocols like OSPF or EIGRP, or converts the device into a controller. These misconceptions arise because candidates confuse security hardening with routing optimization or device functionality. The correct understanding is that disabling unused services strictly reduces the attack surface and exposure, without affecting routing convergence or device roles. Recognizing this prevents choosing answers that sound plausible but do not address the security fundamentals tested in the question.
Technical deep dive
How to think about this question
Disabling unused services on network devices is a fundamental security practice because every active service represents a potential entry point for attackers. Network devices like Cisco routers and switches often run multiple services by default, such as HTTP, Telnet, or SNMP. If these services are not required for the device’s operation or management, they unnecessarily increase the device’s attack surface, exposing it to vulnerabilities and exploitation attempts. Minimizing active services reduces the number of listening ports and protocols, which limits the opportunities for unauthorized access or denial-of-service attacks. The decision to disable unused services follows the principle of least privilege and attack surface reduction. Cisco devices allow administrators to selectively enable or disable services through configuration commands, ensuring only essential services remain active. This hardening process is part of a broader security strategy that includes disabling unused switch ports, applying access control lists (ACLs), and using secure management protocols like SSH instead of Telnet. By removing unnecessary services, network administrators reduce the risk of exploitation without impacting legitimate network functions. A common exam trap is to confuse service disabling with performance improvements or role changes in the device. For example, some may incorrectly believe that disabling services improves routing convergence or transforms the device’s role, which is not true. The practical effect is strictly related to security posture, not routing behavior or device functionality. Understanding this distinction helps avoid selecting incorrect answers that focus on unrelated benefits rather than the core security rationale behind disabling unused services.
KKey Concepts to Remember
- Every enabled service on a Cisco network device increases the attack surface and potential exposure to security threats.
- Disabling unused services follows the principle of least privilege by limiting what is available to potential attackers.
- Cisco IOS allows administrators to disable unnecessary services through configuration commands to harden device security.
- Reducing active services on a device helps prevent unauthorized access and limits exploitation opportunities.
- Disabling unused services does not affect routing protocols like OSPF or EIGRP or improve routing convergence.
- Service hardening does not change the fundamental role or function of a network device such as a router or switch.
- Leaving unnecessary services enabled creates avoidable risk without providing any operational or business value.
- Security best practices include disabling unused services alongside other measures like shutting unused ports and applying ACLs.
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.
CCNA subnetting practice questions
Practise IPv4 subnetting, CIDR, masks, host ranges and subnet selection.
CCNA OSPF practice questions
Practise OSPF neighbours, router IDs, metrics, areas and routing-table interpretation.
CCNA VLAN practice questions
Practise VLANs, access ports, trunks, allowed VLANs and switching scenarios.
CCNA STP practice questions
Practise spanning tree, root bridge election, port roles and STP troubleshooting.
CCNA EtherChannel practice questions
Practise LACP, PAgP, port-channel behaviour and bundle requirements.
CCNA ACL practice questions
Practise standard and extended ACLs, permit/deny logic and traffic filtering.
CCNA NAT practice questions
Practise static NAT, dynamic NAT, PAT and inside/outside address translation.
CCNA DHCP practice questions
Practise DHCP scopes, relay, leases and troubleshooting.
CCNA show ip route practice questions
Practise routing-table output, longest-prefix match, AD and route selection.
CCNA show interfaces trunk practice questions
Practise trunk verification and VLAN forwarding across switches.
CCNA wireless security practice questions
Practise WLAN security, authentication and wireless architecture concepts.
CCNA IPv6 practice questions
Practise IPv6 addressing, routes, neighbour discovery and common IPv6 exam traps.
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?
Every enabled service on a Cisco network device increases the attack surface and potential exposure to security threats.
What is the correct answer to this question?
The correct answer is: Because it reduces unnecessary attack surface and exposure on the device. — It is considered sound because every enabled service is a potential attack surface or management exposure point. In practical terms, if a service is not needed, leaving it enabled creates unnecessary risk without business value. Reducing what is listening or available on a device helps limit opportunities for misuse or exploitation. This is a broader version of the same principle behind shutting unused ports: reduce unnecessary exposure wherever practical.
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.
Discussion
Loading comments…
Sign in to join the discussion.