Juniper Networks ERX Hardware 8 - Manual (Page 123)

Troubleshooting
familiarize yourself with LED activity so that you can easily detect and correct
a module-related problem with minimal or no system downtime.
LED Identification
The system’s modules have two sets of status LEDs. The top set indicates
overall router and module status. The bottom set indicates module-specific
status, such as port status (line modules) or fan status (SRP module).
The number next to the port status LED on a line module corresponds to the
number of the port on the I/O module. Some line modules have more port
status LEDs than the number of ports on the I/O module. In these cases, only
the LEDs for the corresponding ports on the I/O modules are active.
For example, an OCx/STMx line module can pair with either an OC3-4 or
an OC12/STM4 I/O module. Consequently, the line module has four port
status LEDs for OC3/STM1 operation. However, only the top set of port
status LEDs is active during OC12/STM4 operation.
Table 11 presents the functions of the module LEDs and port status LEDs.
Table 11: LED Identification and Activity Descriptions
LED Location LED Label LED Indicator LED Color OFF to ON ON to OFF
OK Module status Green Self-test passed Failure detected
FAIL Module status Red Failure detected Diagnostic test
running
All modules
ONLINE Module status Green Module online Module offline
All modules REDUNDANT Redundancy Green See “Redundancy Status” on page 113.
NOTE: The REDUNDANT LED on the cOCx/STMx, FE-8, GE/FE, HSSI, OCx/STMx,
and X.21/V.35 line modules is nonfunctional.
SRP module POWER A OK Power Green Power online on
source A Power off
POWER B OK Power Green Power online on
source B Power off
FAN OK Fan Green Fan online Critical fan failure
FAN FAIL Fan Red Critical fan failure Fan online
NOTE: When the LED alternates between OK and FAIL at 10-second intervals, a
noncritical fan failure exists.
LINK Ethernet Green Ethernet link up Ethernet link
down
ACTIVITY Ethernet Green Blinks when
Ethernet traffic
on link No Ethernet traffic
on link
Understanding Status LEDs to Troubleshoot 105