Juniper QFX5120 Series User manual

Quick Start Guide
QFX5120 Switch Quick Start
IN THIS GUIDE
System Overview | 1
Tools and Parts Required for Installation | 2
Step 1: Unpack the QFX5120 Switch | 3
Step 2: Mount the Switch on Four Posts of a Rack | 4
Step 3: Connect the QFX5120 Switch to Earth Ground | 9
Step 4: Connect Power to the Switch | 10
Step 5: Perform Initial Configuration | 16
Safety Warnings Summary | 19
Contacting Juniper Networks | 20
System Overview
The Juniper Networks®QFX5120 Switch delivers low-latency, rich Layer 2 and Layer 3 features, VXLAN overlay support,
and 100-Gigabit Ethernet (100GbE) uplinks, making it the ideal switch for access and top-of-rack deployments and for
enterprise multicloud deployments. Featuring Layer 3 gateway capabilities for routing between virtualized and bare-metal
servers, the QFX5120 is designed for extremely agile data centers that demand support for overlay and underlay network
architectures.
The QFX5120 switches are available in three models—QFX5120-32C, QFX5120-48Y, and QFX5120-48T. Each model is
available in two variants featuring AC power supplies with front-to-back or back-to-front airflow and two variants featuring
DC power supplies with front-to-back or back-to-front airflow.
QFX5120-32C switches offer 32 100GbE ports that support quad small form-factor pluggable 28 (QSFP28) transceivers
and 2 10GbE ports that support small form-factor pluggable plus (SFP+) transceivers. Junos OS Release 19.1R1 is the first
Junos OS release that supports QFX5120-32C switches.

QFX5120-48Y switches offer 48 25GbE SFP (SFP28) ports and 8 100GbE QSFP (QSFP28) ports. You can operate each
SFP28 port as a 25GbE, 10GbE, or 1GbE port by using the appropriate transceivers. You can operate each QSFP28 port
as a 100GbE or 40GbE port by using the appropriate transceivers.Junos OS Release 18.3R1 is the first Junos OS release
that supports QFX5120-48Y switches.
QFX5120-48T switches offer 6 100GbE QSFP28 ports and 48 10GbE BASE-T ports. The six QSFP28 ports can operate
at 100-Gbps speed (with QSFP28 transceivers) or 40-Gbps speed (with QSFP+ transceivers). Junos OS Release 20.2R1
is the first Junos OS release that supports QFX5120-48T switches.
You can channelize the QSFP28 ports and connect breakout cables.
NOTE: See the complete documentation at https://www.juniper.net/documentation/product/en_US/qfx5120.
Tools and Parts Required for Installation
Ensure that you have the following parts and tools available:
•Number 2 Phillips (+) screwdriver—not provided
•Electrostatic discharge (ESD) grounding strap—not provided
•Screws to secure the mounting brackets to the rack—not provided
To mount a QFX5120-32C switch on a rack, you need:
•Front mounting brackets—2 (provided with the rack mount kit)
•Side mounting rails—2 (provided with the rack mount kit)
•Flat head M4X8 screws to attach the front mounting brackets and side mounting rails to the switch chassis—20 (provided
with the rack mount kit)
•Rear mounting (L-shaped) brackets—2 (provided with the rack mount kit)
•Pan head M4X8 screws to attach the rear mounting brackets to the side mounting rails—2 (provided with the rack mount
kit)
To mount a QFX5120-48Y or QFX5120-48T switch on a rack, you need:
•Front mounting bracket assembly for mounting the switch flush with the front posts of a rack—2 (provided with the
rack mount kit)
The front mounting bracket assembly is made up of a side rail to which an L-shaped bracket is attached.
•Recessed mounting brackets for mounting the switch in a recessed position from the front posts of a rack—2 (provided
with the rack mount kit)
•Flat head 4x6-mm Phillips screws for attaching the front mounting brackets to the chassis—12 (provided with the rack
mount kit)
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•Flat head 4-40 Phillips screws for attaching the recessed mounting brackets to the side rails—6 (provided with the rack
mount kit)
•Rear mounting brackets—2 (provided with the rack mount kit)
To connect the QFX5120-32C switch to earth ground, you need:
•A grounding cable (minimum 12 AWG (1.5 mm²), minimum 90° wire, or as permitted by the local code), a grounding lug
(4.3-mm circular lug), and one 8-mm screw—not provided
To connect the QFX5120-48Y or QFX5120-48T switch to earth ground, you need:
•A grounding cable (minimum 14 AWG (2.5 mm²), minimum 90° C wire, or as permitted by the local code), a grounding
lug (Panduit LCD10-10A-L or equivalent), and a pair of 10-32 x .25 in. screws with #10 split-lock washers—not provided
To connect power to the switch, you need:
•For all the AC-powered model variants (QFX5120-32C-AFO, QFX5120-32C-AFI, QFX5120-48Y-AFO2,
QFX5120-48Y-AFI2, QFX5120-48T-AFO, and QFX5120-48T-AFI)—An AC power cord with a plug appropriate for your
geographical location, and a power cord retainer—provided.
•For the DC-powered model variants QFX5120-32C-DC-AFO and QFX5120-32C-DC-AFO—12 AWG DC power cable
with a plug—provided
•
•For the DC-powered model variants QFX5120-48Y-DC-AFO2, QFX5120-48Y-DC-AFI2, QFX5120-48T-DC-AFO,
and QFX5120-48T-DC-AFI—14–16 AWG DC power source cables with Molex 190700069 or equivalent ring lugs
attached—not provided
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 https://tools.juniper.net/svcreg/SRegSerialNum.jsp.
Update your installation base at https://www.juniper.net/customers/csc/management/updateinstallbase.jsp.
Step 1: Unpack the QFX5120 Switch
We ship QFX5120 switches in a cardboard carton, secured with foam packing material.
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CAUTION: QFX5120 switches are maximally protected inside the shipping carton. Do not unpack
the switches until you are ready to begin installation.
To unpack the switch:
1. Move the shipping carton to a staging area as close to the installation site as possible, but where you have enough
room to remove the system components.
2. Position the carton so that the arrows marked on the carton are pointing up.
3. Open the top flaps on the shipping carton.
4. Pull out the packing material holding the switch in place.
5. Verify the parts received against the inventory on the label attached to the carton.
6. Save the shipping carton and packing materials in case you need to move or ship the switch later.
Step 2: Mount the Switch on Four Posts of a Rack
You can mount a QFX5120 switch on four posts of a 19-in. rack or a 19-in. cabinet by using a rack mount kit. (The remainder
of this topic uses rack to mean rack or cabinet). You can mount QFX5120-48Y and QFX5120-48T switches in a recessed
position inside the rack.
NOTE:
To ensure that the protective earthing terminal is accessible:
•Ensure that the rack is 27.5 in. (70 cm) through 30.5 in. (77.5 cm) deep if you are mounting the switch flush
with the rack front on four posts of a rack.
•Ensure that the rack is 29.5 in. (75 cm) through 32.5 in. (82.5 cm) deep if you are mounting the switch 2 in.
recessed from the rack front on four posts of a rack.
Before mounting a QFX5120 switch:
•Verify that the site meets the requirements described in Site Preparation Checklist for QFX5120 Switches.
•Place the rack in its permanent location, allowing adequate clearance for airflow and maintenance, and secure the rack
to the building structure.
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•Read General Safety Guidelines and Warnings.
•Ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage (see Prevention
of Electrostatic Discharge Damage).
NOTE: One person must be available to lift the switch while another person secures the switch to the rack.
CAUTION: If you are mounting multiple units on a rack, mount the heaviest unit at the bottom of the
rack, and then mount the other units from the bottom of the rack to the top in decreasing order of
the weight of the units.
To mount a QFX5120 switch:
1. Place the switch on a flat, stable surface.
2. Attach the front mounting brackets.
•If you are mounting a QFX5120-32C switch:
a. Align the front mounting brackets along the side panel of the switch such that the front of the bracket is flush
with the front panel of the switch chassis. Insert the flat head M4X8 screws for attaching the front mounting
brackets into the aligned holes on the chassis and tighten the screws (see Figure 1).
Figure 1: Attach the Front Mounting Brackets to a QFX5120-32C Switch Chassis
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b. Align the side mounting rails along the side panel of the switch. Insert the flat head M4X8 screws for attaching
the side mounting rails into the aligned holes on the chassis and tighten the screws (see Figure 2).
Figure 2: Attach the Side Mounting Rails to a QFX5120-32C Switch Chassis
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•If you are mounting a QFX5120-48Y or QFX5120-48T switch flush with the front posts of a rack:
a. Align the front mounting bracket assembly (provided with the rack mount kit) along the side panel of the switch
such that the front of the bracket is flush with the front panel of the switch chassis.
b. Insert the flat head 4x6-mm Phillips screws for attaching the front mounting brackets (provided with the rack
mount kit) into the aligned holes on the chassis (see Figure 3). Tighten the screws.
Figure 3: Attach the Flush Front Mounting Brackets to a QFX5120-48Y or QFX5120-48T Switch Chassis
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If you are mounting a QFX5120-48Y or QFX5120-48T switch in a recessed position from the front posts of a rack:
a. Unscrew and detach the L-shaped bracket from the side rail in the front mounting bracket assembly (provided
with the rack mount kit).
b. Attach the recessed mounting bracket (provided with the rack mount kit) to the side rail by using the flat head
4-40 Phillips screws provided with the rack mount kit.
c. Align the recessed mounting bracket assembly along the side panel of the switch.
d. Insert the flat head 4x6-mm Phillips screws for attaching the recess mounting bracket assembly (provided with
the rack mount kit) into the aligned holes on the chassis. Tighten the screws.
3. Wrap and fasten one end of the ESD wrist strap around your bare wrist, and connect the other end of the strap to a
site ESD point.
4. Have one person grasp both sides of the switch, lift the switch, and position it in the rack, aligning the holes of the
mounting brackets with the threaded holes in the front post of the rack. Align the bottom hole in both the mounting
brackets with a hole in each rack rail, making sure that the chassis is level.
5. Have a second person secure the front of the switch to the rack by using the screws appropriate for your rack. Tighten
the screws (see Figure 4,Figure 5, and Figure 6).
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Figure 4: Secure the QFX5120-32C Switch to the Front Posts of a Rack to Mount the Switch Flush with the Front
Posts of a Rack
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Figure 5: Secure the QFX5120-48Y Switch to the Front Posts of a Rack to Mount the Switch Flush with the Front
Posts of a Rack
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Figure 6: Secure the QFX5120-48T Switch to the Front Posts of a Rack to Mount the Switch Flush with the Front
Posts of a Rack
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6. Attach the rear mounting brackets.
If you are mounting a QFX5120-32C switch:
a. Ensure that the chassis is level. Align the holes of the rear mounting (L-shaped) brackets with the threaded holes
in the rear post of the rack. Align the bottom hole in both the mounting brackets with a hole in each rack rail. Align
the bottom hole in both the rear mounting brackets with the bottom hole in the front mounting brackets.
b. Secure the rear mounting brackets to the rear post of the rack by using screws appropriate for your rack (see
Figure 7). Tighten the screws.
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Figure 7: Secure the QFX5120-32C Switch to the Rear Post of the Rack by Using the Rear Mounting Brackets
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c. Secure the rear mounting brackets to the side mounting rails by using the pan head M4X8 screws provided. Tighten
the screws.
If you are mounting a QFX5120-48Y or QFX5120-48T switch:
a. Slide the rear mounting bracket blades into the side rails of the front mounting brackets attached to the switch
chassis.
b. Ensure that the chassis is level. Align the holes of the rear mounting brackets with the threaded holes in the rear
post of the rack. Align the bottom hole in both the mounting brackets with a hole in each rack rail. Align the bottom
hole in both the rear mounting brackets with the bottom hole in the front mounting brackets.
c. Secure the rear mounting brackets to the rear post of the rack by using screws appropriate for your rack (see Figure 8
and Figure 9).
Figure 8: Secure the QFX5120-48Y Switch to the Rear Post of the Rack by Using the Rear Mounting Brackets
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Figure 9: Secure the QFX5120-48T Switch to the Rear Post of the Rack by Using the Rear Mounting Brackets
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NOTE: We recommend that you install covers in all unused power supply slots.
Step 3: Connect the QFX5120 Switch to Earth Ground
To ensure proper operation and to meet safety and electromagnetic interference (EMI) requirements, you must connect
the switch to earth ground before you connect power to the switch. You must use the protective earthing terminal on
the switch chassis to connect the switch to ground.
NOTE: A ground connection to the protective earthing terminal is not required for an AC-powered switch. The
AC power cords provide adequate grounding when you connect the power supply in the switch to a grounded
AC power outlet by using the AC power cord appropriate for your geographical location.
WARNING: The switch is installed in a restricted-access location.
CAUTION: If an external ground connection is required, ensure that a licensed electrician has attached
an appropriate grounding lug to the grounding cable that you supply. Using a grounding cable with an
incorrectly attached lug can damage the switch.
To ground the QFX5120:
1. Connect one end of the grounding cable to a proper earth ground, such as the rack in which the switch is mounted.
2. Place the grounding lug attached to the grounding cable over the protective earthing terminal (see Figure 10 and
Figure 11). The protective earthing terminal is on the rear panel on a QFX5120-32C switch and on the left panel on a
QFX5120-48Y switch and a QFX5120-48T switch.
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Figure 10: Connect a Grounding Cable to a QFX5120-32C Switch
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Figure 11: Connect a Grounding Cable to a QFX5120-48Y or QFX5120-48T Switch
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3. Secure the grounding lug to the protective earthing terminal with the washers and screws.
4. Dress the grounding cable and ensure that it does not touch or block access to other switch components.
WARNING: Ensure that the cable does not drape where people could trip over it.
Step 4: Connect Power to the Switch
We ship the QFX5120 switches with two power supplies preinstalled. Each power supply is a hot-removable and
hot-insertable field-replaceable unit (FRU) when the second power supply is installed and running: You can install power
supplies in the slots next to the fan modules without powering off the switch or disrupting switch functions.
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