Verifying RSVP LSP Configuration

A

The "show interfaces terse" command will show you which families are configured.

The correct answer to this question is option B, "show mpls lsp".

Explanation: MPLS (Multiprotocol Label Switching) is a protocol used for forwarding network traffic efficiently. In MPLS networks, LSPs (Label Switched Paths) are established between network nodes to provide traffic engineering and traffic isolation capabilities. RSVP (Resource Reservation Protocol) is a signaling protocol used for setting up LSPs in MPLS networks.

In this question, the RSVP LSP is not operational, and it is suspected that the "family mpls" statement was omitted from the device configuration. The "family mpls" statement is used to enable MPLS on an interface.

The operational mode command that can help verify this suspicion is "show mpls lsp". This command displays information about the status of MPLS LSPs on the device, including the ingress and egress interfaces, the LSP's operational status, and the label stack assigned to the LSP.

If the "family mpls" statement was indeed omitted from the device configuration, the "show mpls lsp" command would display the LSP as inactive or not established, indicating that the LSP is not operational. This would confirm the suspicion that the "family mpls" statement was omitted from the device configuration.

The other answer options provided in the question are not directly related to MPLS or RSVP.

• The "show interface terse" command displays a summary of the interface status and configuration, but it does not provide information about MPLS or RSVP.
• The "show rsvp session" command displays information about the RSVP sessions that are active on the device, but it does not provide information about the status of MPLS LSPs.
• The "show rsvp interface" command displays information about the RSVP interfaces on the device, but it does not provide information about the status of MPLS LSPs.