Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A network engineer wants a static route to be used only when the OSPF-learned route disappears. Which configuration approach meets that goal?
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
Use a static route with administrative distance 1
AD 1 would make the static route preferred immediately.
B
Best answer
Use a static route with administrative distance higher than 110
OSPF uses AD 110, so the backup static route must be higher.
C
Distractor review
Use a static route with metric 0
Static routes do not compete with OSPF using metric in that way.
D
Distractor review
Redistribute the static route into OSPF
Redistribution is not needed just to create a backup path.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is selecting a static route with a default or lower administrative distance than OSPF, such as AD 1, which causes the static route to be preferred immediately, overriding the OSPF route. Another common mistake is thinking that adjusting the metric of the static route or redistributing it into OSPF will create a backup route. Metrics influence path selection within routing protocols but do not affect route preference between static and OSPF routes. Redistribution simply advertises the static route dynamically and does not provide failover control. These misunderstandings lead to incorrect configurations that do not meet the requirement of using the static route only when the OSPF route disappears.
Technical deep dive
How to think about this question
Administrative distance (AD) is a fundamental concept in Cisco routing that determines the trustworthiness of routing information sources. Each routing protocol and route type is assigned a default AD value, with lower values indicating higher trust. For example, static routes have an AD of 1 by default, making them the most preferred, while OSPF routes have an AD of 110. When multiple routes to the same destination exist, the router installs the route with the lowest AD into the routing table. To ensure a static route is used only as a backup when the OSPF-learned route disappears, network engineers configure a floating static route. This is done by setting the static route's administrative distance to a value higher than OSPF's 110, such as 115 or 120. This configuration causes the router to prefer the OSPF route under normal conditions and only switch to the static route if the OSPF route fails or is removed from the routing table. Metrics like cost or hop count influence path selection within OSPF but do not affect the preference between static and OSPF routes. A common exam trap is assuming that changing the metric or redistributing static routes into OSPF will create a backup route that activates only when OSPF fails. However, metrics do not influence route preference between static and dynamic routes, and redistribution merely advertises the static route dynamically without controlling failover behavior. Understanding administrative distance and its role in route selection is critical for correctly configuring floating static routes and avoiding misconfigurations that could lead to routing loops or suboptimal path selection.
KKey Concepts to Remember
- Administrative distance (AD) is a value used by Cisco routers to select the best path when multiple routing protocols provide routes to the same destination.
- OSPF routes have a default administrative distance of 110, which determines their preference relative to other routing sources.
- A static route configured with an administrative distance higher than 110 acts as a floating static route, used only if the OSPF route disappears.
- Static routes by default have an administrative distance of 1, making them preferred over OSPF routes unless manually adjusted.
- The router installs the route with the lowest administrative distance into the routing table, ignoring routes with higher AD unless the preferred route fails.
- Metrics such as cost or hop count influence path selection within routing protocols but do not affect route preference between static and dynamic routes.
- Redistributing static routes into OSPF advertises them dynamically but does not create a backup route that activates only when OSPF routes fail.
- Floating static routes provide a reliable backup path by leveraging administrative distance to control route preference and failover behavior.
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?
Administrative distance (AD) is a value used by Cisco routers to select the best path when multiple routing protocols provide routes to the same destination.
What is the correct answer to this question?
The correct answer is: Use a static route with administrative distance higher than 110 — That is a floating static route. You configure the static route with an administrative distance higher than the OSPF route so it stays in reserve until the dynamic path is lost.
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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