Frame Relay troubleshooting Which Cisco IOS command displays line status, protocol status, DLCI numbers, and LMI information for a Frame Relay interface?

Introduction / Context:
Frame Relay was a WAN protocol widely used before MPLS. Troubleshooting Frame Relay requires verifying interface status, Data Link Connection Identifiers (DLCIs), and Local Management Interface (LMI) information. Cisco IOS provides specific commands for this purpose.

Given Data / Assumptions:

• The protocol in use is Frame Relay.
• We want to check DLCI and LMI information.
• We are using Cisco IOS CLI commands.

Concept / Approach:

The show frame-relay pvc command provides detailed information about Frame Relay Permanent Virtual Circuits (PVCs). It displays DLCI status, interface statistics, and LMI status, making it the go-to command for verifying PVC operation.

Step-by-Step Solution:

Verification / Alternative check:

Cisco's Frame Relay configuration and troubleshooting guides confirm this command as the standard for PVC/LMI info.

Why Other Options Are Wrong:

• sh pvc: invalid abbreviation; not a standard IOS command.
• show interface: provides general interface status, but not detailed DLCI/LMI.
• show run: displays configuration, not runtime DLCI/LMI info.
• show controllers: shows hardware-level info, not PVC/LMI details.

Common Pitfalls:

• Using show interface instead of show frame-relay pvc, leading to incomplete information.

Final Answer:

show frame-relay pvc