Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A branch router has only one WAN link connected to an Ethernet handoff from the provider. Which static default route is generally the better choice?
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
Distractor review
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/0
That can work, but it is usually less ideal on multiaccess Ethernet.
B
Best answer
ip route 0.0.0.0 0.0.0.0 198.51.100.1
A next-hop address is generally preferred on Ethernet provider handoffs.
C
Distractor review
ip route 255.255.255.255 255.255.255.255 198.51.100.1
That is a host route, not a default route.
D
Distractor review
No static default route should ever be used on Ethernet.
Static defaults are perfectly valid there.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A common exam trap is selecting a static default route that specifies only the exit Ethernet interface without a next-hop IP address. While this configuration can work, it causes the router to treat all unknown destinations as directly connected on the Ethernet segment. This behavior triggers excessive ARP requests for every unknown IP address, leading to network inefficiency and potential delays. Candidates might incorrectly assume that specifying the interface alone is sufficient, but on multiaccess Ethernet links, this is suboptimal and can cause routing issues.
Technical deep dive
How to think about this question
A static default route is a routing entry that matches all destination IP addresses not found in the routing table, typically configured as 0.0.0.0/0. It directs packets destined for unknown networks to a specified next-hop IP address or exit interface. In Cisco IOS, static routes can be configured with either a next-hop IP address or an exit interface. The choice impacts how the router resolves Layer 2 forwarding and handles ARP requests, especially on multiaccess Ethernet links. When a static default route is configured on an Ethernet interface, specifying the next-hop IP address is preferred. This is because Ethernet is a multiaccess broadcast medium where the router must resolve the MAC address of the next-hop IP using ARP. If only the exit interface is specified without a next-hop IP, the router assumes all unknown destinations are directly connected on that Ethernet segment. This assumption causes the router to send ARP requests for every unknown destination IP, leading to unnecessary ARP traffic and potential delays. The exam trap lies in choosing the static default route with only the exit interface on Ethernet, which might seem simpler but causes inefficient ARP behavior. The correct approach is to specify the next-hop IP address provided by the ISP, allowing the router to ARP once for the next hop and forward all unknown traffic efficiently. This behavior is specific to multiaccess Ethernet links and differs from point-to-point serial links where specifying only the exit interface is acceptable and common.
KKey Concepts to Remember
- A static default route directs all unknown destination traffic to a specified next-hop IP address or exit interface to simplify routing decisions.
- On multiaccess Ethernet links, Cisco routers prefer static default routes that specify a next-hop IP address rather than just an exit interface.
- Using a next-hop IP address in a static default route allows the router to resolve the next hop via ARP, ensuring proper Layer 2 forwarding.
- Specifying only an exit interface on Ethernet can cause the router to treat all destinations as directly connected, leading to excessive ARP requests.
- A static default route with a next-hop IP address is more scalable and reliable on Ethernet WAN links provided by ISPs.
- Host routes (e.g., 255.255.255.255/32) are not suitable as default routes because they only match a single IP address, not all unknown destinations.
- Static default routes are valid and commonly used on Ethernet interfaces, contrary to the misconception that they should be avoided.
- Cisco routers use the administrative distance and routing table rules to prefer static routes with next-hop IPs over those with only exit interfaces on multiaccess links.
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.
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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?
A static default route directs all unknown destination traffic to a specified next-hop IP address or exit interface to simplify routing decisions.
What is the correct answer to this question?
The correct answer is: ip route 0.0.0.0 0.0.0.0 198.51.100.1 — On multiaccess Ethernet, pointing the default route to a next-hop IP address is usually cleaner because the router can resolve the next hop with ARP. Using only the exit interface on Ethernet can make the router treat many destinations as directly connected and trigger unnecessary ARP behavior.
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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