4-3
Cisco uBR905 Router Hardware Installation Guide
OL-0598-01 (9/2000)
Chapter 4
Troubleshooting
Initialization and Self-Test Problems
9.
If all self-tests passed, the Cisco uBR905 router turns off all LEDs except OK and boots the
Cisco IOS image stored in its Flash memory. The OK LED blinks during the boot process. If this
LED does not start to blink, or if it continues blinking for more than ten minutes, see the “Power
Subsystem” section on page 4-6.
10.
If the Cisco IOS image booted successfully, it takes control from the ROM monitor code and turns
the OK LED on solid.
11.
The router starts normal operations after it starts up the Cisco IOS image. At this point, the US,
DSNR and LINK LEDs remain on to indicate that the router is operational and is receiving a
healthy signal:
–
The OK LED indicates that power is supplied to the router and that it has successfully loaded
and is running a Cisco IOS image.
–
The DS LED indicates that the router is locked to a downstream channel.
–
The US LED indicates that the router has established connectivity with the CMTS and is
operating within 6 dB of desired power level (generally within 3 dB).
–
The LINK LED indicates that the cable interface is operational and is connected to the proper
coaxial cable.
–
The DSNR LED reveals that the router is receiving a quality downstream signal with a low
signal-to-noise ratio (SNR) and that is 5 dB above the downstream lock threshold.
–
The ACT LED blinks to indicate activity on the cable interface.
–
The Ethernet 1, 2, 3, 4 LEDs blink to indicate activity from the PCs and other customer
premises devices connected to the corresponding Ethernet ports.
Note
Because the signal-to-noise ratio and lock threshold can drift, they are regularly
checked and the DSNR LED is updated. While this might cause the DSNR LED
to occasionally blink briefly, under normal conditions the DSNR LED remains on.
12.
When the router and computer have booted successfully, you should be able to access an Internet
web site, which will confirm that the router is configured correctly. If you cannot access a web site,
proceed to the “PC Subsystem” section on page 4-8.
Table 4-1
LED Self-Test Failure Codes
LINK
DS
US
MSG
Error Description
ON
Initialization of the memory controller failed.
ON
ON
ON
ON
The self-test of the low registers of the DRAM failed.
ON
ON
The self-test of the processor cache failed.
ON
ON
ON
A memory or controller problem was detected while clearing the
BSS area of the DRAM.
ON
ON
A memory or controller problem was detected while clearing the
remaining DRAM.
