Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 
ON THIS PAGE
 

Removing or Replacing a Member Switch of a Virtual Chassis Configuration

Note:

If the Virtual Chassis is being managed through Juniper Mist, see the following topics for instructions to delete or replace a Virtual Chassis:

You can remove or replace a member switch in a Virtual Chassis without disrupting network service on the other member switches.

If you remove a member switch, you can free up the member ID so it is available to be assigned to a new member switch later.

When you add a new member switch, the Virtual Chassis assigns the next available member ID to it. The Virtual Chassis retains the existing configuration items specific to particular member IDs. The Virtual Chassis applies those items to a replacement member switch that has the same member ID. By default, the Virtual Chassis applies configuration items that are not member-specific to all member switches.

Note:

When you add or delete member switches in a Virtual Chassis configuration, internal routing changes might cause a sub-second temporary traffic loss. Also, if removing a member switch changes a mixed Virtual Chassis into a non-mixed Virtual Chassis, you must remove the mixed mode setting on all member switches of the Virtual Chassis and reboot the Virtual Chassis; network services are disrupted until the Virtual Chassis is up again.

This topic does not apply to:

To remove or replace a member switch of any other EX Series or QFX Series Virtual Chassis, use one of the following procedures that matches what you want to do.

Remove a Member Switch and Make Its Member ID Available for Reassignment to a Different Switch

To remove a switch from a Virtual Chassis without replacing it:

  1. Power off and disconnect the member switch you want to remove from the Virtual Chassis.
  2. If the Virtual Chassis configuration is preprovisioned, on the Virtual Chassis primary, remove the removed switch’s member setting from the preprovisioned configuration.

    If the Virtual Chassis configuration is nonprovisioned, change the mastership-priority values of each member switch as needed to reconfigure the Virtual Chassis roles. See Configuring Primary Role of a Virtual Chassis.

  3. (Optional) If removing a member switch leaves only two remaining member switches in the Virtual Chassis, we recommend you disable split detection in a two-member Virtual Chassis. See Disabling Split and Merge in a Virtual Chassis for details.
  4. Commit any configuration changes made in previous steps.
  5. (For a mixed Virtual Chassis only) If removing this member switch changes the Virtual Chassis from a mixed to a non-mixed Virtual Chassis, you must also remove the mixed-mode setting from the Virtual Chassis. See Understanding Mixed EX Series and QFX Series Virtual Chassis for details on the combinations of switches that comprise a mixed Virtual Chassis. You must reboot the Virtual Chassis for the mode change to take effect. To do this, you can include the reboot option with the request virtual-chassis mode mixed disable command that turns off mixed mode, or reboot all member switches of the Virtual Chassis separately when ready to do so, as shown below.
    Note:

    Step 7 describes how to remove the mixed mode and other settings from the removed switch if needed.

  6. When you remove a member switch from a Virtual Chassis configuration, the primary keeps that member switch’s member ID in reserve. Use the following command on the Virtual Chassis primary to make that member ID available for reassignment:
  7. If you want to use the removed switch as a standalone switch, you must remove any Virtual Chassis configuration items and settings on that switch. For a smooth transition to a new role as a standalone switch, we recommend to revert the switch to its default factory configuration using the request system zeroize command, and then apply the configuration items you want on the switch.

    If you do not want to revert to default factory settings, use commands such as the following to remove Virtual Chassis settings for the mode and VCPs from the removed switch:

    1. If you removed the switch from a mixed-mode Virtual Chassis that is not an EX4300 mixed Virtual Chassis, disable the mixed-mode setting on the switch as follows:

      If you removed a non-multigigabit model EX4300 switch from a mixed EX4300 Virtual Chassis that contains multigigabit EX4300 switches (EX4300-48MP), when you disable mixed mode, you must also disable the special ieee-clause-82 port mode on the removed switch if you want to reconfigure it as a standalone switch or use it in any other type of mixed Virtual Chassis or non-mixed Virtual Chassis. Otherwise, the VCPs on the switch will not connect with other Virtual Chassis members or those ports will not operate properly as network ports.

      In this case, to disable mixed mode and the port mode on the switch:

      See Understanding EX4300 Multigigabit and Other EX4300 Model Switches in a Mixed EX4300 Virtual Chassis for more information about this special port mode on EX4300 switches.

    2. Delete the VCP settings for any ports that were used as VCPs:
    3. Reboot the standalone switch for settings such as mode changes to take effect.

Remove, Repair, and Reinstall the Same Switch

If you need to repair a member switch, you can remove it from the Virtual Chassis configuration without disrupting network service for the other member switches. The primary stores the configuration for the member ID so that it can be reapplied when the member switch (with the same base MAC address) is reconnected.

To remove, repair, and reinstall the member switch:

  1. Power off and disconnect the member switch to be repaired.
  2. Repair, as necessary.
  3. Reconnect the switch and power it on.

Remove a Member Switch, Replace It with a Different Switch, and Reapply the Old Configuration

If you are unable to repair a member switch, you can replace it with a different member switch of the same type while retaining the previous configuration. The primary stores the configuration of the member switch that was removed. When you connect a different member switch, the primary assigns a new member ID, but the old configuration is still stored under the previous member ID of the previous member switch.

To remove and replace a switch and reapply the old configuration:

  1. Power off and disconnect the member switch to be replaced.
    Note:

    See Step 7 in Remove a Member Switch and Make Its Member ID Available for Reassignment to a Different Switch for information on how to disable Virtual Chassis settings from the removed switch if you want to use that switch in a different configuration.

  2. If the replacement member switch has been previously configured, revert that switch’s configuration to the factory defaults. See the request system zeroize command.

    The replacement member switch should be powered on and running with the factory default configuration at the end of this step.

  3. (Recommended for a QFX5100 Virtual Chassis under certain conditions) When you add or replace a QFX5100-24Q switch that is configured in the Routing Engine role in a QFX5100 Virtual Chassis, if the new switch has two EX4600-EM-8F expansion modules, we recommend that you set the primary role priorities on the routing engine members and the new switch to prevent a primary-role switchover to the new switch until after the new switch is completely initialized in the Virtual Chassis.

    Before interconnecting the new switch into the Virtual Chassis in this case, see Add or Replace a QFX5100-24Q Switch with Two Expansion Modules in a QFX5100 Virtual Chassis for details on why, when, and how you should do this step.

    Note:

    You might need to do this even if the new switch has the default factory configuration.

  4. (Required when automatic software update is not enabled on the Virtual Chassis and the new member switch is running a version of Junos OS that is different than the version of Junos OS running on the Virtual Chassis) Ensure that the correct version of Junos OS is or will be installed on the new member switch by performing either of the following tasks:
  5. Connect one link from the replacement member switch to the Virtual Chassis as follows, depending on which type of ports you are using:

    • If you are interconnecting a switch using dedicated Virtual Chassis Ports (VCPs), connect one dedicated VCP on the replacement member switch to a dedicated VCP on another member switch in the Virtual Chassis.

    • If you are interconnecting a switch using optical ports configured as VCPs:

      On the replacement switch, configure the optical ports that you are using to connect to the Virtual Chassis as VCPs. (You should also configure the optical ports on the existing member switches in the Virtual Chassis where the replacement member switch will be connected, if they are not already configured.) To configure an optical port as a VCP:

      Connect one configured optical port VCP on the replacement switch to a configured optical port VCP on another member switch in the Virtual Chassis.

      Note:

      You can set optical port VCPs on a standalone switch before interconnecting one link into an existing Virtual Chassis, or set them after connecting the link. In either case, you must set the ports as VCPs for the primary to detect and complete the process of adding the switch as a member. For more information on setting up VCPs on EX Series switches, see Setting an Uplink Port on an EX Series or QFX Series Switch as a Virtual Chassis Port, and for details on which ports can be configured as VCPs in a QFX Series Virtual Chassis, see Understanding Virtual Chassis Components.

  6. Confirm that the new member switch is now included in the Virtual Chassis configuration on switches with a front-panel LCD by checking the display for the member ID. It should show a member ID in the range from 0 through 9.

    If you are using a switch that does not have an LCD interface, enter theshow virtual-chassis command and view the output to confirm the switch is part of the Virtual Chassis configuration.

  7. Cable the other VCP on the replacement member switch into the Virtual Chassis based on how you planned to interconnect the switch in Step 5 of this procedure.
    CAUTION:

    If you immediately cable both VCPs on the new switch into the existing Virtual Chassis at the same time, a member switch that was already part of the Virtual Chassis might become nonoperational for several seconds. Network traffic to this switch is dropped during the downtime.

    The member switch will return to the normal operational state with no user intervention, and normal operation of the Virtual Chassis will resume after this downtime.

  8. IF you need to update the new member switch’s current member ID to the member ID of the switch that was removed from the Virtual Chassis configuration:

    • In a nonprovisioned Virtual Chassis, issue the request virtual-chassis renumber command on the primary member switch.

    • In a preprovisioned Virtual Chassis, on the primary member switch, reconfigure the member information for the new member switch using the [edit virtual-chassis] member configuration statement.

      To use the same member ID as the member that was replaced, associate the new switch’s serial number (on the back of the switch) with the replaced member ID, as follows:

      Note:

      You can alternatively use the replace configuration editing command to substitute the serial number of the replacement member switch for the replaced member’s serial number in the existing configuration item for the replaced member.

      To configure the new member switch with a different member ID, associate the new switch’s serial number with the desired member ID and then delete the configuration item for the replaced member switch, as follows:

Replace a Member Switch With a Different Type of Switch That Changes the Virtual Chassis to Mixed Mode

If you want to replace a member switch with a different type of switch that changes the Virtual Chassis from a non-mixed to a mixed Virtual Chassis:

  1. Remove the member switch as described in Remove a Member Switch and Make Its Member ID Available for Reassignment to a Different Switch.
  2. Use the configuration procedure for adding a new switch to an existing Virtual Chassis based on the type of switch you are adding. (See the list of related documentation at the bottom of this page.)

See Understanding Mixed EX Series and QFX Series Virtual Chassis for the combinations of switches that comprise a mixed Virtual Chassis.

Related Documentation