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role (MX Series Virtual Chassis)


Hierarchy Level


As part of the preprovisioned configuration for an MX Series Virtual Chassis, assign the role to be performed by each member router in the Virtual Chassis. The preprovisioned configuration permanently associates the member ID and role with the member router’s chassis serial number.


routing-engine—Enable the member router to function as the primary router or backup router of the Virtual Chassis configuration. The primary router maintains the global configuration and state information for both members of the Virtual Chassis, and runs the chassis management processes. The backup router synchronizes with the primary router and relays chassis control information, such as line-card presence and alarms, to the primary router. If the primary router is unavailable, the backup router takes primary role of the Virtual Chassis to preserve routing information and maintain network connectivity without disruption. You must assign the routing-engine role to both members of the Virtual Chassis. When the Virtual Chassis is formed, the software runs a primary-role election algorithm to determine which of the two member routers functions as the primary router and which functions as the backup router of the Virtual Chassis.

line-card—Explicitly configuring a member router with the line-card role is not supported in the current release. However, when split detection is enabled (the default behavior for a Virtual Chassis) and either the Virtual Chassis ports go down or the backup router fails, the primary router takes a line-card role. The line-card role effectively removes the former primary router from the Virtual Chassis configuration until connectivity is restored.

Required Privilege Level

routing—To view this statement in the configuration.routing-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 11.2.