Connecting a QFX3600 Node Device to a QFX3600-I Interconnect Device
Before you begin to cable the QFX3000-M QFabric system data plane:
Review The Hardware Compatibility Tool for information about the optical interface characteristics.
Ensure that you have taken the necessary precautions for safe handling of lasers (see Laser and LED Safety Guidelines and Warnings for the QFX Series).
Ensure you have installed QSFP+ transceivers in each port you are using. See Installing a Transceiver in a QFX Series Device.
Ensure that you have appropriate fiber-optic cables (see Cable Specifications for QSFP+ and QSFP28 Transceivers).
To form the data plane in a QFX3000-M QFabric system, you connect the QSFP+ uplink ports (labeled Q0 through Q7) on the QFX3600 Node device to the QSFP+ ports (labeled Q0 through Q15) on the QFX3600-I Interconnect device (see Figure 1).
By default, four ports (labeled Q0 through Q3) are configured for 40-Gbps uplink connections between your QFX3600 Node device and your Interconnect device. Optionally, you can choose to configure the first eight ports (labeled Q0 through Q7) for the uplink connections (see Configuring the Port Type on QFX3600 Node Devices).

For redundancy, each QFX3600 Node device must be connected to each QFX3600-I Interconnect device. For example, if you have two QFX3600-I Interconnect devices, then at least one uplink port on each QFX3600 Node device must be connected to each QFX3600-I Interconnect device. If you are connecting all four uplink ports to two QFX3600-I Interconnect devices, we recommend connecting two uplink ports to each Interconnect device.
To connect a QFX3600 Node device to a QFX3600-I Interconnect device (see Figure 1):
Do not look directly into a fiber-optic transceiver or into the ends of fiber-optic cables. Fiber-optic transceivers and fiber-optic cables connected to transceivers emit laser light that can damage your eyes.