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Hierarchy Level


On M10i routers only, configure which Compact Forwarding Engine Board (CFEB) is the primary and which is the backup.


By default, the CFEB in slot 0 is the primary and the CFEB in slot 1 is the backup.


slot-number—Specify which slot is the primary and which is the backup.

always—Define this CFEB as the sole device.

preferred—Define this CFEB as the preferred device of at least two.

Required Privilege Level

interface—To view this statement in the configuration.

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

Release Information

Statement introduced before Junos OS Release 7.4.