Adding a New Switch to expand a preprovisioned virtual chassis

Steps to add a new switch to expand a preprovisioned virtual chassis

• Confirm that the new switch is supported as a member of the Virtual Chassis and in the role in which you want to add it. See Understanding EX Series Virtual Chassis and Understanding Virtual Chassis Components for details on the different EX Series switches, switch combinations, and switch roles that are supported or recommended in a Virtual Chassis.
• Ensure the new switch has the same version of Junos OS that is running on the Virtual Chassis primary switch, or the existing Virtual Chassis has the automatic software update feature configured.
• If you have configured the automatic software update feature in the existing Virtual Chassis, the primary switch updates newly added members with the correct software version automatically, if necessary. Otherwise, you must manually install the correct software version. See Understanding Automatic Software Update on Virtual Chassis Member Switches.
• Mounted the new switch in a rack.
• Determine which ports you will use as Virtual Chassis ports on the new switch, and the member ports in the existing Virtual Chassis to which you will interconnect the new switch.
• See Virtual Chassis Port Options for the ports that can be used as VCPs on switches that support Virtual Chassis.

• Made a note of the serial number (the number is on the back of the switch). You will need to edit the Virtual Chassis configuration to include the serial number of the new member switch.

NOTE: Serial number values are case-sensitive.

• Edit the existing Virtual Chassis configuration to include the serial number of the new member switch. The parameters specified in the primary Virtual Chassis configuration file are applied to the new switch after it has been interconnected to an existing member switch.

(If you are using the autoprovisioning feature to add a member switch to an existing preprovisioned Virtual Chassis) Confirmed that the member ports in the Virtual Chassis to which you will interconnect the new switch are not already configured as VCPs. One condition for automatic VCP conversion is that the ports on both sides of the new link must not already be configured as VCPs. See Automatic Virtual Chassis Port (VCP) Conversion for details on the requirements and conditions under which this feature will be invoked.

• (Optional) Configured Ethernet interfaces on different member switches into the same LAG.
• An active member switch might temporarily go down before coming back up as part of this procedure. Having traffic load-balanced across member switches using a LAG helps alleviate traffic loss during this procedure.
• Delete the no-split-detection configuration item if you are expanding a two-member Virtual Chassis with this option configured. We very strongly recommend that you enable the split detection and merge feature for Virtual Chassis configurations with more than two members. This feature is enabled in the default configuration when you initially set up a Virtual Chassis.

• zeroize the new switch >>> request system zeroize.

• If you are adding a new switch to mixed virutal-chassis, set the new switch into mixed mode, and reboot the switch for the mode change to take effect as follows:

user@device> request virtual-chassis mode mixed reboot

• Power off the new switch, and interconnect the unpowered new switch to one member of the existing Virtual Chassis configuration using a supported VCP.

• Connect only one VCP on the unpowered new switch to a VCP on a member switch in the existing Virtual Chassis at this point in the procedure.

• Power on the new switch.

• Set the interconnecting ports as Virtual Chassis Ports (VCPs), if needed:

user@switch> request virtual-chassis vc-port set pic-slot 1 port port-number

• Confirm that the new member switch is now included within the Virtual Chassis configuration by entering the show virtual-chassis command. The new member switch should be listed in the output and the Status is Prsnt.

• Cable the next port into the Virtual Chassis, configuring the ports into VCPs if needed.

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.

2023/06/16 -Creation date