Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?


mru (Congestion Notification Profiles)


Hierarchy Level


Configure the maximum receive unit (MRU) of the interface in bytes. The system uses the MRU and the cable length to calculate the amount of buffer headroom reserved to support priority-based flow control (PFC). The lower the MRU and the shorter the cable length, 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.


For priority 3 traffic, the default MRU value is 2500 bytes.

For priority 4 traffic, the default MRU value is 9216 bytes.

For user-configured priorities, the default MRU value is 2500 bytes.


mru-value—Value of the maximum packet receive unit size in bytes (generally from 1500 to 9216 bytes, 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.

Support added in dscp statement hierarchy in Junos OS Release 17.4R1 for the QFX Series.