Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?


QFX5110-48S Port Panel

The port panel of the QFX5110-48S is primarily comprised of 48 small form-factor pluggable plus (SFP+) and 4 quad small form-factor pluggable solution (QSFP28) ports. It also provides a central location for the Precision Time Protocol (PTP) connections to a grandmaster clock.

This topic describes:

Switch Overview

The port panel of the QFX5110-48S supports 48 logical 10-GbE ports when operating as a standalone switch. These data ports (0 through 47) support either 1-Gbps or 10-Gbps SFP+ transceivers. You can also use SFP+ DAC cables and 10-Gbps active optical cables (AOC) in any access port. Starting in Junos OS Release 18.3R1, the 10-GbE ports also support 100 Mbps.

The remaining 4 QSFP28 ports (48 through 51) support speeds of 40 GbE or 100 GbE. Each port can be configured as an independent 100-GbE port or as an independent 40-GbE port. These port are usually used as uplinks or Virtual Chassis Ports (VCP) on QFX5110 Virtual Chassis or Virtual Chassis Fabric (VCF). In 40-GbE mode, these ports can be channelized using QSFP+ to SFP+ DAC breakout (DACBO) cables.

Figure 1 shows the port panel of the QFX5110-48S.

Figure 1: QFX5110-48S Port PanelQFX5110-48S Port Panel
Electrostatic discharge (ESD) terminal
4 QSFP28 ports
RJ-45 connection to grandmaster clock
Output clock at 10 Mhz
48 SFP+ ports
1 pulse per second (PPS) output connection

Network Ports


When you use the latest OEM part number FCLF8521P2BTL (printed on the transceiver label), you can install 1GbE transceivers (such as QFX-SFP-1GE-T) in any port with no restrictions. The same applies for devices that support 10GbE copper transceivers. However, if you are using the older OEM part number SP7041-M1-JN (not shipped in last 3+ years) instead, do not install 1GbE copper transceivers (such as QFX-SFP-1GE-T) directly above or below another 1GbE copper transceiver. Use only the top row or bottom row to avoid damage to the device caused when the transceivers are installed above or below each other.

The QFX5110-48S device ports (0 to 47) support:

  • 10-Gbps SFP+ transceivers

  • 1-Gbps SFP transceivers

  • SFP+ direct attach copper (DAC) cables

  • SFP+ active optical cables (AOC)

The QFX5110-48S uplink ports (48 to 51) support:

  • 100-Gbps QSFP28 transceivers

  • 40-Gbps QSFP+ transceivers

  • 100-Gbps AOC

  • 40-Gbps AOC (Junos OS 18.3R1 and later)

  • 100-Gbps QSFP28 DAC cables

  • 40-Gbps QSFP+ DAC cables

  • 40-Gbps QSFP+ to SFP+ DACBO cables (40-Gbps breaks out to 10-Gbps for copper connections)

  • 40-Gbps AOCBO cables (40-Gbps breaks out to 10-Gbps for fiber connections)

Channelizing Interfaces

For downstream traffic, the QFX5110-48S has 4 physical or 16 logical ports that can be used for port channelization. The default 100-Gigabit Ethernet ports can be configured as 40-Gigabit Ethernet, and in this configuration can either operate as dedicated 40-Gigabit Ethernet ports or can be channelized to 4 independent 10-Gigabit Ethernet ports using copper or fiber breakout cables.

To channelize the ports, manually configure the port speed using the set chassis fpc slot-number port port-number channel-speed speed command, where the speed can be set to 10-Gigabit Ethernet, 40-Gigabit Ethernet, or 100-Gigabit Ethernet. The ports do not support auto-channelization.

Virtual Chassis and Virtual Chassis Fabric

To connect QFX5110 switches as members in a QFX5110 Virtual Chassis, you need a pair of dedicated ports on each switch and cables that link each member in the Virtual Chassis into a ring topology. Each member in the ring has at least one direct Virtual Chassis port (VCP) connection to a upstream and downstream member. QFX5110 switches are recommended in the primary, backup, or line card role. You may only mix QFX5100 members with QFX5110 members in a QFX5110 Virtual Chassis; no other QFX Series or EX Series switches are supported. See Connecting QFX5110 and QFX5100 Members in a QFX5110 Virtual Chassis for a a diagram of cabling QFX5110 switches in a ring topology.

To connect a QFX5110 switch as a spine or leaf device in a Virtual Chassis Fabric (VCF), you need a pair of dedicated ports and cables that link each spine device and leaf device in the VCF. All spine devices have at least one direct VCP connection to each leaf device in the VCF. See Connecting QFX5110 in a QFX5110 Virtual Chassis Fabric for a cabling diagram.