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traceroute fabric unicast-flow



Trace the path taken by a specific unicast flow (ping) operation across a VLAN on the QFabric system from a source maintenance endpoint (FMEP) to a destination FMEP. The source and destination FMEPs may be on the same Node device, different Node devices connected to the same Interconnect device, or different Node devices connected to different Interconnect devices.

The flow path is the sequence of Packet Forwarding Engine forwarding hops along which the protocol data unit (PDU) travels. The hop-by-hop sequence and number of hops are reported in terms of fabric maintenance intermediate points (FMIPs), which are interfaces on the Packet Forwarding Engine of the Interconnect device. An FMIP sends a response to the source FMEP when the traceroute PDU is received.


dest-fmep-id source-fmep-id

(Optional) ID of the destination FMEP of the traceroute operation.

flow-spec-name flow-specification-name

Name of the flow specification that defines the parameters of the traceroute operation.

fma-name fma-name

Name of the FMA that associates a VLAN with the FMEPs.

forced-fte-interface fte-interface

(Optional) Option to force the fabric ping operation to use the specified FTE interface to inject the PDU into the fabric instead of using the internal forwarding path lookup table to determine the FTE interface.

source-fmep-id source-fmep-id

(Optional) ID of the FMEP that is the source of the traceroute operation.


(Optional) Detailed version of the output display.

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Output Fields

Table 1 lists the output fields for the traceroute fabric-unicast-flow command. Output fields are listed in the approximate order in which they appear.

Table 1: traceroute fabric unicast-flow Output Fields

Field Name

Field Description

Fabric flow traceroute between source source-fmep-name destination destination-fmep-name

Source and destination FMEP names.

Using fabric flow-specification

Name of the flow specification.

Ethernet frame-size

Ethernet frame size.


MAC address of the source FMEP interface.


MAC address of the destination FMEP interface.


EtherType protocol.

Received response from fmip-id, interface

FMIP identifier and interface name of the FMIP that received the PDU and responded to the source FMEP.

Received total number responses

Number of responses that are received after the traceroute operation has finished.

Sample Output

traceroute fabric unicast-flow

Sample Output

traceroute fabric unicast-flow (Verbose)

Release Information

Command introduced in Junos OS Release 12.2.