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Configuring an EX4650 or a QFX Series Virtual Chassis

 

This topic discusses configuring an EX4650 or a QFX Series Virtual Chassis. For information on configuring a Virtual Chassis Fabric (VCF), see Understanding Virtual Chassis Fabric Configuration.

You configure a Virtual Chassis by configuring Virtual Chassis ports (VCPs) on the member switches and interconnecting the switches using the VCPs. The VCPs pass all data and control traffic between member switches in the Virtual Chassis. See Understanding QFX Series Virtual Chassis and Understanding Mixed EX Series and QFX Series Virtual Chassis for details on the switches that can be interconnected into a Virtual Chassis, and the ports on those switches that can be used as VCPs.

When you set up a Virtual Chassis, ideally all the proposed member switches should have the default factory configuration and operating in standalone mode.

  • All the switches interconnected into a Virtual Chassis must be running the same version of Junos OS. See Installing Software Packages on QFX Series Devices.

  • For QFX3500 or QFX3600 switches in a Virtual Chassis, you must download the Junos OS image that supports Virtual Chassis—an image that includes “jinstall-qfx-3-” in the filename when the Junos OS image is downloaded from the Software Center. QFX3500 and QFX3600 switches that are node devices in a QFabric system cannot be part of a Virtual Chassis.

  • For QFX5100 and EX4300 switches in a QFX5100 Virtual Chassis, you must download the software image for the standalone switch. EX Series and QFX switches that are in a Junos Fusion cannot be part of a Virtual Chassis.

  • For a QFX5110 Virtual Chassis with both QFX5110 and QFX5100 switches, all the switches must be running the same Junos OS image that includes “-qfx-5e-” in the Junos OS software package filename.

    Caution

    You must upgrade QFX5100 switches running a Junos OS image with “-qfx-5-” in the software package filename to a “-qfx-5e-” image filename before adding them to a QFX5110 Virtual Chassis, or the Virtual Chassis will not form. See Upgrading a QFX5100 Switch with a USB Device to Join a QFX5110 Virtual Chassis or Virtual Chassis Fabric.

You can set up the Virtual Chassis with either:

  • A preprovisioned configuration—With preprovisioning, you deterministically control the member ID and role assigned to a member switch by tying it to its serial number.

  • A nonprovisioned configuration—Without provisioning, the master sequentially assigns a member ID to other member switches, and determines the role of each member switch using the mastership priority value and other factors in the master election algorithm.

A Virtual Chassis configuration has two switches acting in the Routing Engine role—the master switch and the backup switch. With any Virtual Chassis configuration, we recommend that you always use commit synchronize rather than simply commit to save configuration changes. This make sure the configuration changes are saved to both switches acting as Routing Engines.

Be sure that all switches that are interconnected into a Virtual Chassis are running the same version of Junos OS. See Installing Software Packages on QFX Series Devices.

Understanding the Licensing Requirements for a Virtual Chassis

Feature licenses are required to configure advanced features on a Virtual Chassis.

For a Virtual Chassis deployment, two license keys are recommended for redundancy—one for the device in the master Routing Engine role and the other for the device in the backup Routing Engine role.

For information on the feature licensing requirements for a Virtual Chassis, see Licenses for EX Series or Software Features That Require Licenses on the QFX Series.

You can install the feature licenses after configuring the Virtual Chassis.

Configuring an EX4650 or QFX Series Virtual Chassis with a Preprovisioned Configuration

Preprovisioning a Virtual Chassis configuration allows you to assign the member ID and role for each switch in the Virtual Chassis.

Before you begin, note that you can configure a Virtual Chassis while the cables are or are not physically connected. However, when committing a preprovisioned configuration on the member switches, under certain conditions the switches will autoprovision the ports cabling the member switches together, which means that those ports are automatically converted into Virtual Chassis ports (VCPs) when the Virtual Chassis members detect the link. Conditions for autoprovisioning include having LLDP enabled on the interfaces being used for the VCP links, and neither side of the link already has the port set as a VCP.

Automatic conversion of VCP links can cause links to come up unexpectedly, so if you want to control when the VCP links become active during Virtual Chassis configuration on the member switches, before you start the configuration, you can disable the VCP auto-conversion feature or any of the conditions required for the feature. See Automatic Virtual Chassis Port (VCP) Conversion for details. If the conditions for autoprovisioning the links are not present, you must manually set the ports connecting the member switches as VCPs as described in this procedure.

To set up a Virtual Chassis using a preprovisioned configuration:

  1. Make a list of the serial numbers of all the switches to be connected in a Virtual Chassis configuration. Note

    Serial number values are case-sensitive.

  2. Note the desired role (routing-engine or line-card) of each switch. If you configure the member with a routing-engine role, it is eligible to function as the master or backup Routing Engine . If you configure the member with a line-card role, it is not eligible to function as the master or backup. See Understanding Virtual Chassis Components and Understanding Mixed EX Series and QFX Series Virtual Chassis for details on which switches are recommended or required to be configured into each role depending on the types of switches in the Virtual Chassis.
  3. Power on only the switch that you plan to use as the master switch.
  4. Specify the identification parameters for the switch by completing the initial configuration. See Configuring Junos OS on the EX4650, Configuring a QFX3500 Device as a Standalone Switch or Configuring a QFX3600 Device as a Standalone Switch, Configuring a QFX5100 Device, Configuring a QFX5110, Configuring Junos OS on the QFX5120, or Performing the Initial Software Configuration for QFX5200 Switches.Note

    The properties that you specify for the master switch apply to the entire Virtual Chassis configuration.

  5. (Optional) Configure the master switch with the virtual management Ethernet (VME) interface for out-of-band management of the Virtual Chassis:
    user@switch# set interfaces vme unit 0 family inet address /ip-address/mask/
  6. (Required for a mixed Virtual Chassis only) Set the master switch into mixed mode and reboot the switch to complete the configuration:Note

    You must complete this step if your Virtual Chassis includes a combination of different types of switches, except when you are configuring a Virtual Chassis that includes only QFX3500 and QFX3600 switches or only QFX5110 and QFX5100 switches (which are considered to be non-mixed Virtual Chassis). See Understanding Mixed EX Series and QFX Series Virtual Chassis for details.

    user@device> request virtual-chassis mode mixed reboot

  7. After the reboot is complete, specify the preprovisioned configuration mode:
    [edit virtual-chassis]

    user@switch# set preprovisioned

  8. Specify all the members that you want included in the Virtual Chassis, listing each switch’s serial number with the desired member ID and role:
    [edit virtual-chassis]

    user@switch# set member 0 serial-number abc123 role routing-engine

    user@switch# set member 1 serial-number def456 role routing-engine

    user@switch# set member 2 serial-number ghi789 role line-card

    user@switch# set member 3 serial-number jkl012 role line-card



  9. (Optional. Recommended for a two-member Virtual Chassis) Disable the split and merge feature:
    [edit virtual-chassis]

    user@switch# set no-split-detection



  10. Commit the configured items.
  11. Power on the other member switches. The member IDs and roles have been determined by the configuration, so you can power on the member switches in any order.
  12. (Required if you are configuring a mixed Virtual Chassis) Set each individual switch into mixed mode and reboot the switch to complete the configuration:Note

    You must complete this step if your Virtual Chassis includes a combination of different types of switches, except when you are configuring a Virtual Chassis that includes only QFX3500 and QFX3600 switches or only QFX5110 and QFX5100 switches (which are considered to be non-mixed Virtual Chassis). See Understanding Mixed EX Series and QFX Series Virtual Chassis for details.

    user@device> request virtual-chassis mode mixed reboot

  13. (Optional, if the VCP links will not be autoprovisioned) On each individual member switch, configure the ports that you will use to interconnect the member switches into VCPs:Note

    SFP+, QSFP+, and 10-Gbps copper links between two member switches will be automatically set as VCPs (auto-provisioned) in a preprovisioned configuration under certain conditions. The required conditions on both sides of the link include having automatic VCP conversion enabled on the switches, LLDP enabled on the interfaces being used as VCPs, and those ports are not already set as VCPs. . (See Automatic Virtual Chassis Port (VCP) Conversion.)

    This step is optional and should only be used when a VCP link is not automatically created.



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

    where pic-slot-number is the PIC slot number.

    For example, if you wanted to set port 0 on the QSFP+ interface on PIC slot 2 as a VCP:



    user@switch> request virtual-chassis vc-port set pic-slot 2 port 0
    Note

    You can include the local option if you want to make sure the command applies only to that port locally on the switch where you’re running the command.

    The VCPs automatically bundle into a Link Aggregation Group when two or more interfaces of the same speed are configured into VCPs between the same two member switches. See Understanding Virtual Chassis Port Link Aggregation.

Note

You cannot modify the mastership priority when you are using a preprovisioned configuration. The mastership priority values are generated automatically and controlled by the role that is assigned to the member switch in the configuration file. The two Routing Engines are assigned the same mastership priority value. However, the member that was powered on first has higher priority according to the master election algorithm. See Understanding How the Master in a Virtual Chassis Is Elected.

Note

If you want to change the member ID of a preprovisioned member switch later, you must re-configure the member information for that member switch using the member configuration statement. For example, to re-configure member 3 (which has serial number “jkl012”) to have 6 as its new member ID, you associate member ID 6 with the serial number of member 3, and then delete the configuration item for member ID 3, as follows:

[edit virtual-chassis]

user@switch# set member 6 serial-number jkl012

user@switch# delete member 3



The request virtual-chassis renumber command can only be used to change a Virtual Chassis member ID in a nonprovisioned Virtual Chassis.

Configuring an EX4650 or a QFX Series Virtual Chassis with a Nonprovisioned Configuration

You can use a nonprovisioned configuration to set up an EX4650 or a QFX Series Virtual Chassis.

To configure the Virtual Chassis using a nonprovisioned configuration:

Note

You can configure the Virtual Chassis while the cables are or are not physically connected.

  1. Power on only the switch that you plan to use as the master switch.
  2. (Required for a mixed Virtual Chassis only) Set the master switch into mixed mode and reboot the switch to complete the configuration:Note

    You must complete this step if your Virtual Chassis includes a combination of different types of switches, except when you are configuring a Virtual Chassis that includes only QFX3500 and QFX3600 switches or only QFX5110 and QFX5100 switches (which are considered to be non-mixed Virtual Chassis). See Understanding Mixed EX Series and QFX Series Virtual Chassis for details.

    user@device> request virtual-chassis mode mixed reboot

  3. After the master switch reboots, specify the identification parameters for the switch by completing the initial configuration. See Configuring Junos OS on the EX4650, Configuring a QFX3500 Device as a Standalone Switch, Configuring a QFX3600 Device as a Standalone Switch, Configuring a QFX5100 Device, Configuring a QFX5110, Configuring Junos OS on the QFX5120, or Performing the Initial Software Configuration for QFX5200 Switches for details. Note

    The properties that you specify for the master switch apply to the entire Virtual Chassis configuration.

  4. (Optional) Configure the master switch with the virtual management Ethernet (VME) interface for out-of-band management of the Virtual Chassis:
    user@switch# set interfaces vme unit 0 family inet address /ip-address/mask/
  5. (Optional) Configure mastership priority for the member switches:
    [edit virtual-chassis]

    user@switch# set member 0 mastership-priority 255

    user@switch# set member 1 mastership-priority 255

  6. (Optional. Recommended for a two-member Virtual Chassis) On the master switch, disable the split and merge feature:
    [edit virtual-chassis]

    user@switch# set no-split-detection

  7. Commit the configured items.
  8. Power on the other member switches.
  9. (Required for a mixed Virtual Chassis only) Set each individual switch into mixed mode and reboot the switch to complete the configuration:Note

    You must complete this step if your Virtual Chassis includes a combination of different types of switches, except when you are configuring a Virtual Chassis that includes only QFX3500 and QFX3600 switches or only QFX5110 and QFX5100 switches (which are considered to be non-mixed Virtual Chassis). See Understanding Mixed EX Series and QFX Series Virtual Chassis for details.

    user@device> request virtual-chassis mode mixed reboot

  10. On each individual member switch, configure the ports that will be used to interconnect the member switches into VCPs using the following command:


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

    where pic-slot-number is the PIC slot number.

    For example, if you wanted to set port 0 on the QSFP+ interface on PIC slot 2 as a VCP:



    user@switch> request virtual-chassis vc-port set pic-slot 2 port 0
    Note

    You can include the local option if you want to make sure the command applies only to that port locally on the switch where you’re running the command.

    The VCPs automatically bundle into a Link Aggregation Group when two or more interfaces of the same speed are configured into VCPs between the same two member switches. See Understanding Virtual Chassis Port Link Aggregation.

Note

If you don’t set mastership priorities on any member switches, the default mastership priority value is128. If the mastership priorities are the same on all members, the master election algorithm determines the member switches in the master and backup Routing Engine roles based on the other factors in the algorithm. You control the role settings by configuring the mastership priority to a higher number on the switches you want to be the master and backup members. .(see Configuring Mastership of a Virtual Chassis). We recommend that you specify the same mastership priority value for the members you want to be the master and backup members. This example assigns the highest possible mastership priority to two members. However, the member that was powered on first has higher priority according to the master election algorithm. See Understanding How the Master in a Virtual Chassis Is Elected for details on all the factors considered when electing the master. The other members have the default mastership priority in this example, and they become linecard role members.

Note

If you want to change the member ID that the master automatically assigned to a member switch, use the request virtual-chassis renumber command.