Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?


Tools and Parts Required for Installation


See the complete hardware documentation at

To mount a Juniper Networks QFX5120 Ethernet Switch on four posts of a rack, you need:

  • Four mounting brackets and eight mounting screws—provided

  • Screws to secure the chassis to the rack or cabinet—not provided

  • Phillips (+) screwdriver, number 2—not provided

  • Electrostatic discharge (ESD) grounding strap—not provided

  • Fan module—if not installed

To connect the switch to earth ground, you need:

  • A grounding cable (minimum 14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code), a grounding lug (Panduit LCC10-14BWL or equivalent), a pair of 10-32 x .25-in. screws with #10 split-lock washers, and a pair of #10 flat washers—none provided

To connect power to the switch, you need:

  • For models that are powered by AC power—An AC power supply (if not already installed), an AC power cord with a plug appropriate for your geographical location, and a power cord retainer

  • For models that are powered by DC power—A DC power supply (if not already installed) and DC power source cables (12-14–AWG—not provided) with ring lugs (Molex 0190700067 or equivalent—not provided) attached

To perform initial configuration of the switch, you need:

  • An Ethernet cable with an RJ-45 connector attached—provided

  • An RJ-45 to DB-9 serial port adapter—provided

  • A management host, such as a PC, with an Ethernet port—not provided

Register product serial numbers on the Juniper Networks website and update the installation base data if there is any addition or change to the installation base or if the installation base is moved. Juniper Networks will not be held accountable for not meeting the hardware replacement service-level agreement for products that do not have registered serial numbers or accurate installation base data.

Register your product at

Update your install base at

The fan modules and the power supply modules in the QFX5120 switches are hot-removable and hot-insertable field-replaceable units (FRUs) installed in the rear panel of the switch. You can remove and replace them without powering off the switch or disrupting switch functions.


Do not mix:

  • AC and DC power supplies in the same chassis.

  • Power supplies and fan modules with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.


Ensure that you understand how to prevent ESD damage. Wrap and fasten one end of an ESD wrist strap around your bare wrist, and connect the other end of the strap to the ESD point on the switch.


Power supplies and fan modules must have same airflow direction (all AFI or all AFO). The AIR IN (AFI) or AIR OUT (AFO) labels, respectively, on the power supplies and must match with the AIR IN (AFI) or AIR OUT (AFO) labels respectively on the fan modules.