VC for EX3400

For uplink:   both QSFP+ ( 40G  ) or SFP+ ( 10G ) can be used

SPF, SPF+, QSPF, QSFP+, SFP28, QSFP28 and DAC



https://www.juniper.net/documentation/en_US/release-independent/junos/topics/topic-map/ex3400-system-overview.html#jd0e102

Virtual Chassis

You can interconnect a maximum of 10 EX3400 switches to form a Virtual Chassis. You can operate these interconnected switches as a single, logical device with a single IP address.

You can use the following ports to interconnect an EX3400 switch in a Virtual Chassis:

  • QSFP+ ports configured as VCPs by using QSFP+ transceivers

  • NOTE

    You cannot form a Virtual Chassis by using SFP transceivers.

    Uplink ports on the front panel configured as VCPs by using SFP+ transceivers

By default, the QSFP+ ports are configured as VCPs.