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Step 1: Begin


In this guide, we provide a simple, three-step path, to quickly get you up and running with your new EX3400. We’ve simplified and shortened the installation and configuration steps, and included how-to videos. You’ll learn how to install an AC-powered EX3400, power it up, and configure basic settings.


Are you interested in getting hands-on experience with the topics and operations covered in this guide? Visit Juniper Networks Virtual Labs and reserve your free sandbox today! You’ll find the Junos Day One Experience sandbox in the stand alone category. EX switches are not virtualized. In the demonstration, focus on the virtual QFX device. Both the EX and QFX switches are configured with the same Junos commands.

Meet the EX3400 Ethernet Switch

The Juniper Networks EX3400 Ethernet Switches are a cost-effective solution for today’s most demanding converged data, voice, and video enterprise access networks. The fixed-configuration 1-RU switches are perfect for campus wiring closet deployments. They offer levels of performance and management previously available only with high-end access switches.

The EX3400 switches support Power over Ethernet (PoE) and Power over Ethernet Plus (PoE+) ports for powering attached network devices.

You can interconnect up to 10 EX3400 switches to form a Virtual Chassis and thus manage these switches as a single logical device.

In this guide, we show you how to install the following EX3400 AC-powered switch models:

  • EX3400-24T: 24 10/100/1000BASE-T ports, four SFP+ uplink ports

  • EX3400-24P: 24 10/100/1000BASE-T PoE/PoE+ ports, four SFP+ uplink ports

  • EX3400-48T: 48 10/100/1000BASE-T ports, four SFP+ uplink ports

  • EX3400-48P: 48 10/100/1000BASE-T PoE/PoE+ ports, four SFP+ uplink ports

Install the EX3400 Switch

You can install the EX3400 switch on a desk or table, on a wall, or in a two-post or four-post rack. The accessory kit that ships in the box has the brackets you need to install the EX3400 switch in a two-post rack. In this guide, we walk you through how to do that.


If you want to mount the switch on a wall or in a four-post rack, you’ll need to order a wall mount or rack mount kit. The four-post rack mount kit also has brackets for mounting the EX3400 switch in a recessed position in the rack.

What’s in the Box?

  • EX3400 switch

  • An AC power cord appropriate for your geographical location

  • Two mounting brackets and eight mounting screws

  • An Ethernet cable with RJ-45 connectors attached and an RJ-45 to DB-9 serial port adapter

  • Power cord retainer clip

What Else Do I Need?

You’ll also need:

  • Someone to help you secure the switch to the rack

  • Mounting screws to secure the EX3400 to the rack

  • A number two Phillips (+) screwdriver

  • A serial-to-USB adapter (if your laptop doesn’t have a serial port)

Install the EX3400 in a Two-Post Rack

  1. Review General Safety Guidelines and Warnings
  2. Attach the mounting brackets to the sides of the EX3400 switch using the eight screws that came in the box and the screwdriver.

    You’ll notice there are three locations on the side panel where you can attach the mounting brackets: front, center, and rear. Attach the mounting brackets to the location that best suits where you want the EX3400 switch to sit in the rack.

  3. Lift the EX3400 switch and position it in the rack. Line up the bottom hole in each mounting bracket with a hole in each rack rail, making sure the EX3400 switch is level.
  4. While you’re holding the EX3400 switch in place, have someone insert and tighten the rack mount screws to secure the mounting brackets to the rack rails. Make sure to tighten the screws in the two bottom holes first and then tighten the screws in the two top holes.
  5. Check that the mounting brackets on each side of the rack are level.

Power On

Now you’re ready to connect the EX3400 switch to a dedicated AC power source. The switch comes with the AC power cord for your geographic location.

Here’s how to connect an EX3400 switch to AC power:

  1. On the rear panel, connect the power cord retainer clip to the AC power supply:
    1. Push the end of the power cord retainer strip into the slot above the power cord socket until the strip snaps into place. Ensure that the loop in the retainer strip faces the power cord. The power cord retainer clip extends out of the chassis by 3 in. (7.62 cm).
    2. Press the small tab on the retainer strip to loosen the loop. Slide the loop until there is enough space to insert the power cord coupler into the power cord socket.
    3. Plug in the power cord to the power cord socket.
    4. Slide the loop toward the power supply until it is snug against the base of the coupler.
    5. Press the tab on the loop and draw out the loop into a tight circle.

  2. If the AC power outlet has a power switch, turn it off.
  3. Plug in the power cord to the AC power outlet.
  4. If the AC power outlet has a power switch, turn it on.

The EX3400 switch powers up as soon you connect it to power. It doesn’t have a power switch. When the SYS LED on the front panel is lit solid green, the switch is ready to use.