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request chassis sfm master switch



(M40e and M160 routers only) Control which Switching and Forwarding Module (SFM) is primary.



(Optional) Do not display a switch warning or query.

Additional Information

By default, the SFM in slot 0 (SFM0) is the primary and the SFM in slot 1 (SFM1) is the backup. If you use this command to change the primary, and then restart the chassis software for any reason, the primary reverts to the default setting. To change the default primary SFM, include the sfm statement at the [edit chassis redundancy] hierarchy level in the configuration. For more information, see the Junos OS Administration Library for Routing Devices.

All installed SFMs are always working together to forward packets. If an SFM fails, the other SFMs take over and traffic continues to flow uninterrupted.

Required Privilege Level


Output Fields

When you enter this command, you are provided feedback on the status of your request.

Sample Output

request chassis sfm primary switch

request chassis sfm primary switch no-confirm

Release Information

Command introduced before Junos OS Release 7.4.