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cable-length (Congestion Notification)


Hierarchy Level


Specify the length of the cable between the interface and its peer interface in meters. The system uses the cable length and the maximum receive unit (MRU) to calculate the amount of buffer headroom reserved to support priority-based flow control (PFC). The the shorter the cable length and lower the MRU, the less headroom buffer space is required for PFC.


You can also set a maximum transmission unit (MTU) value (the largest packet size the interface sends) for interfaces by including the mtu statement at the [edit interfaces interface-name] hierarchy level.


The default cable length value is 100 meters (approximately 328 feet).


cable-length-value—Length of the cable in meters. (Generally from 1 to 300 meters, but there is no configuration restriction.)

Required Privilege Level

interfaces—To view this statement in the configuration.

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

Release Information

Statement introduced in Junos OS Release 12.3.