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many-to-one (Aggregated Multiservices)


Hierarchy Level


Configure the many-to-one (N:1) preferred backup for the aggregated multiservices (AMS) interface.


The preferred backup must be one of the member interfaces (mams–) that have already been configured at the [edit interfaces interface-name load-balancing-options] hierarchy level. Even in the case of mobile control plane redundancy, which is one-to-one (1:1), the initial preferred backup is configured at this hierarchy level.


preferred-backup preferred-backup

Use the specified interface as the preferred backup member interface. The member interface format is mams-a/b/0, where a is the FPC slot number and b is the PIC slot number.

Required Privilege Level

interface—To view this statement in the configuration.

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

Release Information

Statement introduced in Junos OS Release 11.4.

Support added in Junos OS Release 19.3R2 for Next Gen Services on MX Series routers MX240, MX480 and MX960 with the MX-SPC3 services card.