350-501 Question #154: Real Exam Question with Answer & Explanation

Question

A network engineer is implementing BFD configuration changes on a customer's equipment. How is the bfd interval configuration on the interface disconnected?

Options

• AThe status of the interface changes.
• BThe IPv4 or IPv6 address configuration on the interface changes.
• CIt is automatically disconnected when the BFD-configured subinterface is removed.
• DIt is automatically disconnected when the BFD main interface is removed.

Explanation

The BFD interval configuration on an interface is automatically disconnected when the main physical interface itself is removed from the device's configuration.

Common mistakes.

• A. A change in the interface's operational status (e.g., going down) causes the BFD session to terminate, but it does not remove or 'disconnect' the underlying BFD interval configuration from the running configuration.
• B. Changing the IPv4 or IPv6 address on an interface might cause the existing BFD session to break and re-establish, but the bfd interval configuration itself remains applied to the interface.
• C. Removing a BFD-configured subinterface disconnects BFD for that specific subinterface, but the question asks about the 'main interface' and D is a more encompassing answer if the main interface itself is removed.

Concept tested. BFD Configuration Lifecycle

Reference. https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_bfd/configuration/xe-16-10/ird-xe-16-10-book/ird-bfd-intf.html

No community discussion yet for this question.