Understanding Virtual Chassis EX 4200 Switch Version Compatibility
For EX 4200 switches to be interconnected as a Virtual Chassis configuration, the switches must be running the same software versions. The master checks the hardware version, JUNOS software version, and other component versions running in a switch that is physically interconnected to its Virtual Chassis port (VCP). Different hardware models can be members of the same Virtual Chassis configuration. However, the master will not assign a member ID to a switch that is running a different software version. A switch that is running a different version of software will not be allowed to join the Virtual Chassis configuration.
