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Taking an MX2000 Host Subsystem Offline

To take a host subsystem offline:

  1. Determine whether the host subsystem is functioning as the primary or as the backup, using one of the two following methods:
    • Check the Routing Engine LEDs on the craft interface. If the green MASTER LED is lit, the corresponding host subsystem is functioning as the primary.

    • Issue the following command. The primary Routing Engine is designated Master in the Current state field:

  2. If the host subsystem is functioning as the primary, switch it to backup by using the command:

    When you request the host subsystem primary to switch to backup, a message appears indicating that the network traffic will be interrupted while the Packet Forwarding Engine is reinitialized.

  3. On the console or other management device connected to the Routing Engine you are removing, enter CLI operational mode and issue the following command. The command shuts down the Routing Engine cleanly, so its state information is preserved:

    When you request a host subsystem halt, only one Routing Engine will be halted. You must use the request chassis both-routing-engines command to halt both Routing Engines.

    Wait until a message appears on the console confirming that the operating system has halted.

    For more information about the command, see the Junos OS System Basics and Services Command Reference.


    The Routing Engine might continue forwarding traffic for approximately 5 minutes after the request system halt command has been issued.