Which CLI command verifies the status of a configured loopback interface?

The show interfaces loopback command is the standard and most direct method in ArubaOS-CX to verify the operational status of a configured loopback interface. This command provides comprehensive details, including the administrative state (e.g., up/down), the link state, and other essential interface parameters and counters. For a virtual interface like a loopback, this command confirms if it is active and recognized by the system's control plane.

A. show ip interface loopback primarily displays Layer 3 (IP protocol) information for the interface, not its fundamental administrative or link status.
B. display loopback uses the display keyword, which is common in the Comware operating system (used by H3C/HPE) but is not the correct syntax for ArubaOS-CX.
D. show loopback state is not a valid command in the ArubaOS-CX command-line interface for checking the status of a loopback interface.

1. ArubaOS-CX 10.13 CLI Reference Guide, Page 1881, "show interface". The documentation specifies the command show interface [loopback ] and describes its function as showing "interface configuration information, status, and statistics." This confirms it is the correct command to verify the status.

2. ArubaOS-CX 10.12 Fundamentals Guide, Page 121, "Verifying the loopback interface configuration". The guide provides an example: switch# show interface loopback 0, which displays the "Admin state" and "Link state" as part of its output, directly addressing the question's requirement to verify status.