An engineer configures a static backup route on router R1 for remote destination subnet . The primary path to this subnet is learned dynamically via OSPFv2. During baseline verification, the engineer discovers that traffic destined for routes over the backup WAN circuit even though the primary OSPF link is active and in the FULL state. Which configuration issue on router R1 explains why the backup route is active in the routing table?
- The static route was configured without specifying a custom administrative distance, causing it to use the default administrative distance of 1, which beats the OSPF administrative distance of 110.Answer
- BThe static route was configured with an administrative distance of 120, which is higher than OSPF and forces the router to install both routes simultaneously.
- CThe static route was configured with an administrative distance of 110, forcing equal-cost load balancing across both the OSPF path and the static backup path.
- DThe static route was configured with an administrative distance of 95, which correctly floats behind OSPF routes but overrides them when link latency increases.
Answer
The static route was configured without specifying a custom administrative distance, causing it to use the default administrative distance of 1, which beats the OSPF administrative distance of 110.
In Cisco IOS, static routes configured without an explicit administrative distance inherit the default value of 1. Because routers populate the IP routing table by choosing the path with the lowest administrative distance when multiple sources report the same prefix, a static route with AD 1 will take precedence over an OSPF route with AD 110. To act as a floating static route, the static route's administrative distance must be manually set higher than the primary routing protocol's AD (for example, setting AD to 115 or 120).
Step-by-Step Solution
Key Concept
Floating Static Route Administrative Distance Configuration
Estimated Time:2m 0s