You can view the colors of the three LEDs remotely through the CLI by issuing the operaonal mode
command show chassis led.
user@host> show chassis led
-----------------------------------
LEDs status:
Alarm LED : Red
Beacon LED: Off
System LED: Green
Interface STATUS LED LINK/ACTIVITY LED
---------------------------------------------------------
et-0/0/0 N/A Off
et-0/0/1 N/A Off
et-0/0/2 N/A Off
et-0/0/3 N/A Off
et-0/0/4 N/A Off
et-0/0/5 N/A Off
et-0/0/6 N/A Off
et-0/0/7 N/A Off
et-0/0/8 N/A Off
et-0/0/9 N/A Off
et-0/0/10 N/A Green
et-0/0/11 N/A Off
et-0/0/12 N/A Off
et-0/0/13 N/A Off
et-0/0/14 N/A Off
et-0/0/15 N/A Off
et-0/0/16 N/A Green
et-0/0/17 N/A Off
et-0/0/18 N/A Green
et-0/0/19 N/A Off
et-0/0/20 N/A Off
et-0/0/21 N/A Off
et-0/0/22 N/A Off
et-0/0/23 N/A Off
et-0/0/24 N/A Off
et-0/0/25 N/A Off
et-0/0/26 N/A Green
et-0/0/27 N/A Green
et-0/0/28 N/A Green
et-0/0/29 N/A Off
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