Juniper EX4500 Hardware Manual page 219

CAUTION:
Virtual Chassis module is not supported.
EX4500 switches running Junos OS Release 10.4R2 or later 10.4 releases will not boot
if you do not install the intraconnect module in the switch.
EX4500 switches running Junos OS Release 11.1R1 or later releases will not boot if
you install neither the intraconnect module nor the Virtual Chassis module in the
switch.
Before you begin installing the Virtual Chassis module in the switch:
Ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage
(see "Prevention of Electrostatic Discharge Damage" on page
Have instructions and tools available for removing and installing the fan tray. If the fan tray is installed,
you must remove it as part of the procedure for installing the Virtual Chassis module. After you install
the module, you must install the fan tray. See
and "Installing a Fan Tray in an EX4500 Switch" on page
Ensure that you have the following parts and tools available:
ESD grounding strap
Phillips (+) screwdriver, number 2
A replacement Virtual Chassis module
NOTE: You must remove the fan tray from the EX4500 switch before installing the Virtual
Chassis module. See
Operating an EX4500 switch without the intraconnect module or the
"Removing a Fan Tray from an EX4500 Switch" on page 190
"Removing a Fan Tray from an EX4500 Switch" on page
305).
192.
190.
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