Reading LEDs
The following table summarizes the LEDs on the chassis of the router. These LEDs are common to all chassis
models, however, these LEDs may be turned off using Cisco IOS CLIs. By default all three LEDs are enabled.
Description
Color/State
Function
LED Label
System is in ROM Monitor
(ROMMON) mode
Off
System status
1
No hardware failure detected;
system is in Cisco IOS prompt
mode
Green
Minor hardware failure
detected
Amber
Major hardware failure (critical
temperature or voltage)
detected
Red
No power
Off
Management status
2
System booted fine and is in
Cisco IOS prompt mode
Green
Software upgrade is in progress
(MCU or ROMMON)
Amber
Cisco IOS boot in progress or
in ROMMON mode
Red
Fast Ethernet port and slot not
connected
Off
Network status
3
Fast Ethernet port and
slot
—
link and line protocol is
up.
Green
Fast Ethernet port and
slot
—
administration is down
Amber
Fast Ethernet port and
slot
—
line protocol is down
Red
Cisco ASR 901S Series Aggregation Services Router Hardware Installation Guide
78
OL-29732-01
Troubleshooting
Reading LEDs