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• 10MHZ (one input and one output)—The 10-MHz timing connectors connect the switch to external
clock signal sources. The clocking ports provide the synchronized output clocks from any one of the
reference clock inputs based on the clock’ s priority.
• PPS (one input and one output)—1-pulse-per-second (PPS) connectors connect the switch to external
clock signal sources. The clocking ports provide the synchronized output clocks from any one of the
reference clock inputs based on the clock’ s priority.
• USB—The USB port provides a removable media interface. Junos OS supports USB version 1.0 and
later.
describes the functions of the LEDs on the REs.
Table 6: LEDs on the Routing Engines in an EX9253 Switch
LED
Color
State
Description
ONLINE
Green
On steadily
Both Junos OS and Linux
are successfully loaded on
the switch.
Blinking
The switch is starting
Junos OS.
Red
On steadily
The switch has loaded
Linux.
Blinking
The switch is starting
Linux.
–
Off
The switch is offline.
OK/FAIL
Green
On steadily
The switch is functioning
normally.
Red
Blinking
The switch has failed.
–
Off
The switch is not
powered on.
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