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show loop-detect enhanced interface



Display status information about leaf device interfaces with loop detection enabled in an EVPN-VXLAN fabric.

In an EVPN-VXLAN fabric, you can configure loop detection on leaf devices for server-facing Layer 2 interfaces, and specify an action that the leaf device performs on the interface when it detects a loop, such as bringing the interface down. You can also configure an interval after which the device will automatically revert the interface to its state prior to the loop detection action following repair of the loop condition.

After you’ve enabled loop detection, the interfaces periodically send multicast loop-detection protocol data units (PDUs). If the interface receives a loop-detection PDU, which indicates a loop exists, the interface triggers the configured action to break the loop. The network administrator might then need to repair the conditions that caused the loop before reverting the interface to its state prior to loop detection. This command shows the configured loop detection parameters, current interface status, and detail about the remote interface that formed the loop.



Display loop detection status for the specified interface.

If you don't specify an interface name, this command displays loop detection status for all interfaces that have this feature enabled.

Required Privilege Level


Output Fields

Table 1: show loop-detect enhanced interface Output Fields
Field Name Field Description


Local interface name with loop detection configured.


Local interface VLAN ID for which loop detection is configured.


Ethernet Segment ID (ESI) associated with the local interface.

Current status

Current status of the interface—Loop-detected or Normal [Link Up] (no loop detected)

This output section displays the following additional fields if the interface detected a loop. These fields describe the interface that routed loop detection PDUs back to the local interface:

  • Remote Host: Remote host name.

  • Remote Chassis: Remote host chassis ID.

  • Remote Interface: Remote interface name that is looping PDUs.

  • Remote ESI: ESI associated with the remote interface.


The interface causing the loop might be on the same local device or on a remote device.

Last loop-detect time

Timestamp when the device initially detected the loop and changed the interface status to Loop-detected.

Receive statistics

Number of loop-detection PDUs received since the current loop detection period timestamp.

Action configured

The configured action that the device triggers upon loop detection.

Action count

Cumulative count of loop detection actions triggered on the local interface.

Transmit Interval

Default or configured interval at which the interface sends loop detection PDUs.

Revert Interval

Configured interval after the loop condition is repaired in which the interface state reverts to the previous state before the loop detection action occurred.

Sample Output

show loop-detect enhanced interface interface-name (no loop detected)

show loop-detect enhanced interface interface-name (loop detected)

show loop-detect enhanced interface (EX4300-48MP, all interfaces configured with loop detection)

show loop-detect enhanced interface (ACX7100-32C, ACX7100-48L, all interfaces configured with loop detection, no loop detected)

Last loop-detect time displays the time at which first loop was detected.

Note: In non-revertive mode or when revert timer is running (after a loop is cleared) and if new loop is detected, last loop-detect time will be updated to display the recent loop detected time.

show loop-detect enhanced interface (ACX7100-32C, ACX7100-48L, all interfaces configured with loop detection, loop detected)

Release Information

Command introduced in Junos OS Release 20.4R1.