To display QSFP+ interface information on a Juniper EX4300 switch, use the show interfaces terse command. You can also use show interfaces or show interfaces <interface_name> for more detailed information about a specific QSFP+ port. The show chassis hardware command can also be helpful in identifying and verifying the presence of QSFP+ ports. 

Detailed Explanation:

• show interfaces terse

  This command provides a concise overview of all configured interfaces, including QSFP+ ports. It displays basic information such as the interface name, status, speed, and link status. 

• show interfaces

  This command shows detailed information about all interfaces, including QSFP+ ports. It provides more comprehensive data compared to the terse version, including statistics, counters, and other operational details. 

• show interfaces <interface_name>

  This command displays detailed information about a specific interface, allowing you to focus on a particular QSFP+ port. Replace <interface_name> with the name of the QSFP+ port (e.g., et-0/1/0). 

• show chassis hardware

  This command provides a detailed view of the switch's hardware components, including the presence and type of QSFP+ ports. It's helpful for verifying the existence and configuration of QSFP+ modules. 

Example:

To see all interfaces, including QSFP+ ports, you would use:

show interfaces terse

To see detailed information about the et-0/1/0 port: 

Code

show interfaces et-0/1/0

Additional Notes:

• The EX4300 switches can utilize QSFP+ ports for various purposes, including Virtual Chassis backplane connections and high-speed uplinks. 
• If a QSFP+ port is not listed in the show interfaces terse output, it may indicate that the interface driver (IFD) is not being created for the optics. In such cases, you can try enabling LLDP (Link Layer Discovery Protocol) on the interface to restore it, according to Juniper Support Portal. 
• It's crucial to verify that the correct QSFP+ optics (transceivers) are installed in the ports for proper operation.