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Configuring an EX2300, EX3400, or EX4300 Virtual Chassis

 

You can use the procedures in this topic to configure:

  • A non-mixed Virtual Chassis composed of EX2300, EX3400, or EX4300 switches

  • A mixed EX4300 Virtual Chassis with EX4300 multigigabit model (EX4300-48MP) switches interconnected with other EX4300 model switches

You can mix non-multigigabit model EX4300 switches with other switches in a Virtual Chassis or Virtual Chassis Fabric (VCF) in the following supported combinations. In these cases, use the following configuration procedures instead of the procedures in this topic:

Use the following requirements and guidelines to plan the devices to include in your Virtual Chassis:

  • EX2300 switches:

    In Junos OS releases prior to 18.4R1, you can interconnect EX2300 and EX2300-C switches into a Virtual Chassis, or you can interconnect EX2300 multigigabit model switches (EX2300-24MP and EX2300-48MP) into a Virtual Chassis. You can’t combine EX2300 or EX2300-C switches with EX2300 multigigabit model switches in a Virtual Chassis.

    Starting in Junos OS Release 18.4R1, you can combine EX2300, EX2300-C, and EX2300 multigigabit switches in the same non-mixed Virtual Chassis, and use any of these switches in any role (master Routing Engine role, backup Routing Engine role, or linecard role).

  • EX3400 switches:

    You can interconnect EX3400 switches only with other EX3400 switches in a Virtual Chassis (no mixed mode).

  • EX4300 switches:

    You can interconnect EX4300 switches excluding multigigabit models into a non-mixed EX4300 Virtual Chassis.

    You can also connect EX4300 multigigabit model switches (EX4300-48MP) together into a non-mixed EX4300 Virtual Chassis.

    You can combine EX4300 multigigabit model switches with other EX4300 model switches as a mixed EX4300 Virtual Chassis with the following configuration:

    • You must configure the Virtual Chassis into mixed mode.

    • You must also include a special port mode option (ieee-clause-82) when you configure mixed mode on the EX4300 switches that are not multigigabit models. This port mode enables the Virtual Chassis ports (VCPs) on EX4300 non-multigigabit model switches to communicate with VCPs on multigigabit model members.

      Note

      If you remove a non-multigigabit model EX4300 switch from a mixed EX4300 Virtual Chassis with multigigabit model members, remember to disable 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 will not connect with other members in the new Virtual Chassis. (See Removing or Replacing a Member Switch of a Virtual Chassis Configuration.)

    • The members in the Routing Engine role must be multigigabit model (EX4300-48MP) switches.

Use these guidelines to plan the VCP connections:

  • In a non-mixed EX4300 Virtual Chassis with only EX4300 multigigabit model (EX4300-48MP) switches, interconnect the member switches using the dedicated VCPs—the 40-Gpbs QSFP+ ports on the rear panel. These are the only ports that can be used as VCPs on EX4300-48MP switches.

  • In a mixed EX4300 Virtual Chassis with a combination of EX4300 multigigabit model switches and other EX4300 model switches, you must use 40-Gbps QSFP+ ports on the other EX4300 model switches as VCPs and interconnect those ports with the dedicated VCPs on the multigigabit model switch members.

    Note

    All QSFP+ ports on EX4300 non-multigigabit switches are configured as VCPs in the default factory configuration.

  • In non-mixed EX2300, EX3400, and non-multigigabit model EX4300 Virtual Chassis, use uplink ports that you configure as VCPs or that are VCPs by default to interconnect the member switches. Keep the following in mind about VCPs on these switches:

    • EX2300 switches do not have any ports that are configured by default as VCPs. You must explicitly configure the ports you want to use as VCPs.

    • The QSFP+ uplink ports on EX3400 and EX4300 switches support 40-Gbps speeds and can connect switches that are up to 492 feet (150 m) apart. These are set as VCPs by default, so you don’t need to explicitly configure them.

    • You can configure the SFP+ uplink ports on any of these switches as VCPs. These ports support 10-Gbps speeds and can connect switches that are up to 6.2 miles (10 km) apart.

      Note

      The only exceptions are the four built-in 10-Gbps SFP+ ports on 32-port EX4300 switches. You can’t use the built-in ports as VCPs.

    • You can’t use uplink ports installed with SFP transceivers as VCPs on any of these switches.

  • The simplest way to interconnect EX3400 or EX4300 switches into a non-mixed EX3400 or EX4300 Virtual Chassis is to install the switches within 492 feet of one another and interconnect them into a Virtual Chassis by using the QSFP+ ports.

    For an EX3400 or EX4300 Virtual Chassis, if you must install member switches in locations that are more than 492 feet apart (such as at a different site or at a distant location within the same site), or if you are using the QSFP+ ports for another purpose, or for any EX2300 Virtual Chassis, you must configure SFP+ uplink module ports into VCPs.

  • If you need additional VCP bandwidth between two member switches, you can configure additional ports as VCPs and create redundant links between the member switches.

    Redundant VCP links are not required to be the same speed, but the links with identical speeds automatically form a VCP link aggregation group (LAG) to provide resiliency to the Virtual Chassis. For example, if you have two 40-Gbps QSFP+ ports and two 10-Gbps SFP+ ports configured as VCPs connecting the same two member switches to each other, the member switches form two LAGs—one LAG with two 40-Gbps QSFP+ port links and another with two 10-Gbps SFP+ port links.

Note

A Virtual Chassis configuration has two Routing Engines—the master switch and the backup switch. We recommend that you always use commit synchronize rather than simply commit to save configuration changes made for a Virtual Chassis. This ensures that you save the configuration changes on both Routing Engines at the same time.

An EX2300, EX3400, or EX4300 Virtual Chassis can be configured with either of the following options:

  • A nonprovisioned configuration—The master sequentially assigns a member ID to other member switches. The role is determined by the mastership priority value and other factors in the master election algorithm.

  • A preprovisioned configuration—You can deterministically control the member ID and role assigned to a member switch by tying the member switch to its serial number.

All member switches must be running the same version of Junos OS to form a Virtual Chassis.

Note

You must configure a VLAN on all interfaces in the Virtual Chassis, except on member switch 0, before the interfaces can send or receive traffic. This is because the interfaces on member switch 0 are initially placed into the default VLAN, but the interfaces on all other member switches are not placed into any VLAN. See Configuring VLANs for EX Series Switches with ELS Support (CLI Procedure).

Note

On an EX4300 Virtual Chassis, STP is disabled on all interfaces except the interfaces on member switch 0 until some type of spanning-tree protocol is enabled. See Configuring RSTP on EX Series Switches (CLI Procedure) (RSTP is the default spanning-tree protocol), Configuring MSTP on Switches, or Configuring VSTP Protocol to enable a spanning-tree protocol on the interfaces in your EX4300 Virtual Chassis.

Configuring an EX2300, EX3400, or EX4300 Virtual Chassis with a Nonprovisioned Configuration File

You can use a nonprovisioned configuration to configure an EX2300, EX3400, or EX4300 Virtual Chassis.

This procedure shows example configuration steps for a Virtual Chassis with two to ten members. You can have up to 4 members in an EX2300 Virtual Chassis, and up to 10 members in an EX3400 or EX4300 Virtual Chassis.

Note

We recommend that you physically cable the interconnecting ports as the final step of this procedure.

You can, however, configure the Virtual Chassis while the cables are physically connected.

  1. Power on only the switch that you will use as the master switch.Note

    For a mixed EX4300 Virtual Chassis with EX4300 multigigabit model (EX4300-48MP) switches and other EX4300 model switches, the members in the master and backup Routing Engine roles must be EX4300 multigigabit model switches.

  2. (Required for a mixed EX4300 Virtual Chassis only) Set the master switch into mixed mode, and reboot the switch for the change to take effect:
    user@device> request virtual-chassis mode mixed reboot

  3. If you are configuring a mixed Virtual Chassis, wait for the reboot to complete before performing this step.

    Run the EZSetup program on the master switch, specifying the identification parameters. See Connecting and Configuring an EX Series Switch (CLI Procedure) 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 (see Understanding Global Management of a Virtual Chassis):
    [edit]

    user@switch# set interfaces vme unit 0 family inet address /ip-address/mask/
  5. (Optional) Configure mastership priority for the other member switches. For example, for a ten-member Virtual Chassis:
    [edit virtual-chassis]

    user@switch# set member 0 mastership-priority 255

    user@switch# set member 1 mastership-priority 255

    user@switch# set member 2 mastership-priority 10

    user@switch# set member 3 mastership-priority 9

    user@switch# set member 4 mastership-priority 8

    user@switch# set member 5 mastership-priority 7

    user@switch# set member 6 mastership-priority 6

    user@switch# set member 7 mastership-priority 5

    user@switch# set member 8 mastership-priority 4

    user@switch# set member 9 mastership-priority 3

    The mastership priority value determines the roles in a non-provisioned Virtual Chassis configuration. The switches with the highest mastership priority values assume the master and backup roles. All other switches assume the linecard role.

    If you do not configure the mastership priority for any switch in your Virtual Chassis, including when you do not configure the Virtual Chassis, all switches assume the default mastership priority of 128. The master election algorithm selects the roles for the member switches. In most cases, the switches that have been powered on the longest assume the master and backup roles when all Virtual Chassis member switches are configured with the same mastership priority. See Understanding How the Master in a Virtual Chassis Is Elected for additional information on the master election algorithm.

    A switch with a mastership priority of 0 never assumes the master or backup role.

    Note

    We recommend that you specify the same mastership priority value for the intended master and backup members.

  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 EX4300 Virtual Chassis only) Set each additional individual EX4300 multigigabit model (EX4300-48MP) switch into mixed mode and reboot the switch for the change to take effect:
    user@device> request virtual-chassis mode mixed reboot

    Set each of the other EX4300 switches that are not multigigabit model switches into mixed mode with the ieee-clause-82 option, and reboot the reboot the switch for the change to take effect:

    user@device> request virtual-chassis mode ieee-clause-82 mixed reboot

  10. If needed, on each individual member switch, configure SFP+ uplink ports that will be used as VCPs to interconnect the member switches. Note

    This step is not needed for EX4300 multigigabit model (EX4300-48MP) switches, which have dedicated VCPs on the rear panel of the switch. Dedicated VCPs do not require configuration, and you must use the dedicated ports on these switches because no other ports on these switches are supported as VCPs.

    Note

    On EX3400 switches and on EX4300 member switches that are not multigigabit model switches, because QSFP+ ports are configured into VCPs by default, you do not usually have to perform this step when you are using a QSFP+ port as a VCP. You only need to configure a QSFP+ port as a VCP if you previously configured the QSFP+ port into a network port. If you previously configured the QSFP+ port into a network port, perform this step to configure the QSFP+ port back into a VCP.

    Use the request virtual-chassis vc-port command to configure SFP+ or QSFP+ ports into VCPs. For example, for a four-member Virtual Chassis:

    user@switch-0> request virtual-chassis vc-port set pic-slot 1 port 0
    user@switch-0> request virtual-chassis vc-port set pic-slot 1 port 1
    user@switch-1> request virtual-chassis vc-port set pic-slot 1 port 0
    user@switch-1> request virtual-chassis vc-port set pic-slot 1 port 1
    user@switch-2> request virtual-chassis vc-port set pic-slot 1 port 0
    user@switch-2> request virtual-chassis vc-port set pic-slot 1 port 1
    user@switch-3> request virtual-chassis vc-port set pic-slot 1 port 0
    user@switch-3> request virtual-chassis vc-port set pic-slot 1 port 1
  11. Cable the ports interconnecting the members if they were not connected earlier.
Note

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

Configuring an EX2300, EX3400, or EX4300 Virtual Chassis with a Preprovisioned Configuration File

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

This procedure shows example configuration steps applicable to a Virtual Chassis with two to ten members; up to 4 members are supported in an EX2300 Virtual Chassis, and up to 10 members are supported in an EX3400 and EX4300 Virtual Chassis.

To configure a Virtual Chassis using a preprovisioned configuration:

Note

We recommend that you physically cable the optical ports as the final step of this procedure.

You can, however, configure the Virtual Chassis while the cables are physically connected.

  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 intended role (routing-engine or line-card) of each switch. If you configure the member with a routing-engine role, it is eligible to function in the master or backup role. If you configure the member with a line-card role, it is not eligible to function in the master or backup role.Note

    For a mixed EX4300 Virtual Chassis with EX4300 multigigabit model (EX4300-48MP) switches and other EX4300 model switches, the members in the master and backup Routing Engine roles must be EX4300 multigigabit model switches.

  3. Power on only the switch that you plan to use as the master switch.
  4. (Required for a mixed EX4300 Virtual Chassis only) Set the master switch into mixed mode, and reboot the switch for the change to take effect:
    user@device> request virtual-chassis mode mixed reboot

  5. If you are configuring a mixed Virtual Chassis, wait for the reboot to complete before performing this step.

    Run the EZSetup program on the master switch, specifying the identification parameters. See Connecting and Configuring an EX Series Switch (CLI Procedure) for details.Note

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

  6. (Optional) Configure the master switch with the virtual management Ethernet (VME) interface for out-of-band management of the Virtual Chassis (see Understanding Global Management of a Virtual Chassis):
    [edit]

    user@switch# set interfaces vme unit 0 family inet address /ip-address/mask/
  7. 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. For example, for a ten-member Virtual Chassis:Note

    You can retrieve the switch’s serial number using the show chassis hardware command output or by viewing the serial number ID label on the switch. See Locating the Serial Number on an EX2300 Switch or Component, Locating the Serial Number on an EX3400 Switch or Component, or Locating the Serial Number on an EX4300 Switch or Component. Serial number values are case-sensitive.

    [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

    user@switch# set member 4 serial-number mno013 role line-card

    user@switch# set member 5 serial-number pqr014 role line-card

    user@switch# set member 6 serial-number stu015 role line-card

    user@switch# set member 7 serial-number vwx016 role line-card

    user@switch# set member 8 serial-number yzz017 role line-card

    user@switch# set member 9 serial-number aaa018 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 for a mixed EX4300 Virtual Chassis only) Set each additional individual EX4300 multigigabit model (EX4300-48MP) switch into mixed mode and reboot the switch for the change to take effect:
    user@device> request virtual-chassis mode mixed reboot

    Set each of the other EX4300 switches that are not multigigabit model switches into mixed mode with the ieee-clause-82 option, and reboot the reboot the switch for the change to take effect:

    user@device> request virtual-chassis mode ieee-clause-82 mixed reboot

  13. If needed, on each individual member switch, configure the SFP+ uplink ports that will be used as VCPs to interconnect the member switches. Note

    This step is not needed for EX4300 multigigabit model (EX4300-48MP) switches, which have dedicated VCPs on the rear panel of the switch. Dedicated VCPs do not require configuration, and you must use the dedicated ports on these switches because no other ports on these switches are supported as VCPs.

    Note

    On EX3400 switches and on EX4300 member switches that are not multigigabit model switches, because QSFP+ ports are configured into VCPs by default, you do not usually have to perform this step when you are using a QSFP+ port as a VCP. You only need to configure a QSFP+ port as a VCP if you previously configured the QSFP+ port into a network port. If you previously configured the QSFP+ port into a network port, perform this step to configure the QSFP+ port back into a VCP.

    Use the request virtual-chassis vc-port command to configure SFP+ or QSFP+ ports into VCPs. For example, for a four-member Virtual Chassis:

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

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

    user@switch-2> request virtual-chassis vc-port set pic-slot 1 port 0
    user@switch-2> request virtual-chassis vc-port set pic-slot 1 port 1

    user@switch-3> request virtual-chassis vc-port set pic-slot 1 port 0
    user@switch-3> request virtual-chassis vc-port set pic-slot 1 port 1

  14. Cable the ports interconnecting the members if they were not connected earlier.
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 prioritization according to the master election algorithm. See Understanding How the Master in a Virtual Chassis Is Elected.