Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

Setting an Uplink Port on an EX Series or QFX Series Switch as a Virtual Chassis Port

 

Use the procedures described in this topic to set up Virtual Chassis ports (VCPs) to connect two switches togetherin an EX Series or a QFX Series Virtual Chassis.

Switches that can be members of a Virtual Chassis might have:

  • Dedicated VCPs—Ports you can use only as VCPs.

  • Default-configured VCPs—Ports that are already configured into VCPs with the default factory configuration. On some switches these ports can alternatively be converted back into and used as uplink or network ports.

  • Uplink or network ports that are also supported as VCPs—Ports you can configure into VCPs and convert back into uplink or network ports as needed.

If you don’t have or are not using dedicated or default-configured VCPs, you need to convert supported ports into VCPs to interconnect Virtual Chassis members. When a switch has uplink or network ports that can be converted into VCPs, you can use some ports as VCPs and others as network ports or uplinks to other devices in trunk mode. When you set a port as a VCP, you can’t use it for any other purpose.

You can set ports as VCPs on a standalone switch before interconnecting any links into a Virtual Chassis, or set them after interconnecting one link on the switch into an existing Virtual Chassis. Either way, after the VCP is connected into the Virtual Chassis, the master switch uses the link to detect the switch and complete the process of adding it as a member.

Note

Most Virtual Chassis also support autoprovisioning, which means that under certain conditions, when you interconnect a member switch into an existing Virtual Chassis, ports that are supported as VCPs will convert automatically into VCPs when you cable the link. This is an easy way to add member switches to a Virtual Chassis without needing to explicitly configure VCPs, but it only works if the ports on both sides of the link are not already configured as VCPs. If you want to use autoprovisioning, you might need to delete VCP settings (whether default-configured or those you previously set explicitly) on either or both sides of the links you are using to interconnect the new member switch. See Automatic Virtual Chassis Port (VCP) Conversion for details.

See Virtual Chassis Port Options for a list of supported VCP ports on each type of switch. For complete details about where a switch has dedicated VCPs, default-configured VCPs, or ports that can be configured as VCPs, and what transceivers and cables are supported to use for VCP connections on that switch, see the hardware documentation for the switch. In general, even if a port is supported as a VCP, you can’t use it as a VCP if it’s channelized.

When to Configure VCPs

You typically configure a port as a Virtual Chassis Port (VCP) for one of the following reasons:

  • You are configuring a Virtual Chassis composed of switches that support Virtual Chassis but do not have default-configured VCPs or dedicated VCPs.

  • You are using default-configured VCPs or dedicated VCPs to interconnect members in a Virtual Chassis, and want to add redundant VCP links between members using additional ports that can be configured into VCPs.

  • You want to interconnect two switches into a Virtual Chassis that have dedicated VCPs but are located in different wiring closets or sites, and the switches are farther apart then the maximum length of a dedicated VCP cable.

  • You previously changed a default-configured VCP to use it as a network or uplink port, and now you want to use it as a VCP again.

We recommend that you have two uplink VCP connections within each wiring closet for redundancy. VCPs automatically bundle into a Link Aggregation Group when two or more ports operating at the same speed are configured into VCPs between the same two member switches. See Understanding Virtual Chassis Port Link Aggregation for details.

Caution

If you set a port as a VCP to create a redundant link with a dedicated VCP connection on EX4200, EX4500, or EX4550 switches, to avoid traffic looping within the Virtual Chassis, you must reboot the Virtual Chassis after configuring the port conversion and cabling the VCP link. See Troubleshooting an EX Series Virtual Chassis for more information.

Prepare Virtual Chassis Member Switches Before Converting VCPs

Before converting a port into a VCP and interconnecting the switch into a Virtual Chassis:

  1. Verify which ports can be used as VCPs in your particular configuration. See Virtual Chassis Port Options for a summary of the VCP options on switches that support Virtual Chassis, and the hardware documentation for each type of switch for complete details about the ports and installed transceivers that can be used as VCPs.
  2. If you are configuring an uplink module port as a VCP, if needed, install the uplink module in the member switches that you want to interconnect.
  3. Log into the switch that is or will be the master of the Virtual Chassis.Note

    Do not power on the other switches at this point.

  4. (EX Series switches only) Run EZSetup on the switch that you are configuring to be the master member switch. Make sure the hostname and other identification, time zone, and network properties are set up on the master. See Connecting and Configuring an EX Series Switch (CLI Procedure) for details. The parameters you specify for the master apply to the entire Virtual Chassis, including all the member switches that you interconnect later.
  5. If you want to configure and manage the Virtual Chassis remotely, specify the VME global management interface. You can configure the VME global management interface when you are setting up the master or you can do it after completing the other configuration steps for the Virtual Chassis. See Configuring the Virtual Management Ethernet Interface for Global Management of an EX Series Virtual Chassis (CLI Procedure).
  6. Configure mastership of the Virtual Chassis using either a nonprovisioned or preprovisioned configuration. See Configuring Mastership of a Virtual Chassis for details.
Note

A Virtual Chassis has two Routing Engines, one in the master role and the other in the backup role. Therefore, we recommend that you always use commit synchronize rather than simply commit to save configuration changes made for a Virtual Chassis. This ensures that the configuration changes are saved in both Routing Engines.

Before you begin to interconnect new Virtual Chassis members across long distances, such as between wiring closets:

  • Prepare the existing Virtual Chassis for interconnecting with a potential member switch that is beyond the reach of a dedicated Virtual Chassis cable by setting at least one uplink VCP on an existing member of the Virtual Chassis.

  • Prepare the potential member switch for interconnecting with the existing Virtual Chassis by setting at least one uplink VCP on the standalone switch.

From the Virtual Chassis, you can set an uplink port on the local member or on a specified member as a VCP.

Note

On EX4200 switches, if you use an SFP+ uplink module, you must configure all member switches to support either 1-gigabit SFP transceivers or 10-gigabit SFP+ transceivers. See Setting the Mode on an SFP+ or SFP+ MACSec Uplink Module .

To set the uplink ports for the local member switch (for example, member 0) and for a different member switch (for example, member 1) to function as VCPs:

  1. Set one uplink port of member 0 as a VCP. You don’t need to specify the member member-id option, because the command applies by default on the member where it is executed.


    user@switch> request virtual-chassis vc-port set pic-slot 1 port 0
  2. Set one uplink port of member 1 as a VCP. This step includes the member member-id option because it acts on a different member switch than the local member switch.


    user@switch> request virtual-chassis vc-port set pic-slot 1 port 0 member 1

    Note

    You can also connect to a member switch individually using the request session member command, and set a VCP locally on that member. (As in Step 1, you don’t specify the member option in that case.)

You can set an uplink VCP on a standalone switch before interconnecting the link into an existing Virtual Chassis. You must set the port as a VCP for the Virtual Chassis master to detect the switch and complete the process of adding it as a member.

To set one uplink VCP on the potential member, which is currently operating as a standalone switch:

  1. Power on the standalone switch.
  2. Set one uplink port as a VCP. You do not need to specify the member member-id option, because the command applies by default on the member where it is executed.


    user@switch> request virtual-chassis vc-port set pic-slot 1 port 0
    Note

    If you do specify the member member-id option, use member ID 0. Because the switch is not yet interconnected with the other members of the Virtual Chassis, its current member ID is 0. Its member ID will change when it is interconnected with the Virtual Chassis. It does not impact the functioning of the uplink VCP that its VCP is set with 0 as the member ID. The VCP has significance only on the local switch.

  3. After you have set the uplink VCP on the standalone switch, physically interconnect its uplink port with a VCP uplink port on one of the members in the existing Virtual Chassis.

    The new member switch reboots and joins the now expanded Virtual Chassis with a different member ID.

    Note

    The setting for the new member switch's uplink VCP remains intact and is not affected by the change of member ID.

  4. Repeat the steps above to interconnect the new switch to another member of the Virtual Chassis or to create redundant VCP links to the same member.

You might want to convert a VCP back into an uplink or network port if:

  • You want to use a default-configured VCP on a switch as a network or uplink port instead of as a VCP.

  • You want to add a new member switch or a new VCP link in an existing Virtual Chassis using autoprovisioning, where the VCP links form automatically when you cable them only if the ports on both sides of the link are not already set as VCPs. (See Automatic Virtual Chassis Port (VCP) Conversion for details.)

  • You remove a switch from a Virtual Chassis and want to use it as a standalone switch again.

    Note

    In this case, whenever possible we recommend that you revert the switch back to its default factory configuration to guarantee the smoothest transition back to standalone operation. See Removing or Replacing a Member Switch of a Virtual Chassis Configuration.

To remove the VCP setting on a port:

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

You usually do this on the switch with the VCP itself, so you don’t need to include the member member-id option because the command applies by default on the member where you run it.