4-2
Cisco uBR905 Router Hardware Installation Guide
OL-0598-01 (9/2000)
Chapter 4
Troubleshooting
Initialization and Self-Test Problems
Initialization and Self-Test Problems
When the Cisco uBR905 router first powers on, it performs the following self-test and initialization
routines:
1.
The primary ROM monitor in Flash memory tests the secondary ROM monitor. If the secondary
ROM monitor is present in Flash memory and passes its verification tests, it assumes control and
continues with the initialization process; otherwise, the primary ROM monitor continues with the
initialization process.
2.
The system runs its diagnostic procedures, which ensure that all Cisco uBR905 components are
functioning. To complete the diagnostic procedures, the Cisco uBR905 processor must be able to:
–
Perform a system reset trap.
–
Fetch and execute instructions from the ROM Monitor area of the Flash memory.
–
Write several internal registers and reset the control processor successfully.
–
Correctly configure the port registers.
–
Perform conditional branches.
–
Verify that the software-controlled LEDs are functional.
If all diagnostic procedures are successful, all LEDs except for the four Ethernet and the ACT LEDs
briefly blink.
3.
The next step of the self-test initializes the memory controller. The US LED comes on if this test
succeeds.
4.
The console port is initialized and the banner is output to the console port.
5.
Next, the Cisco uBR905 router performs a self-test on the low memory area of the DRAM. When
this test starts, the LINK, DS, US, and MSG LEDs come on.
6.
After testing low memory, the processor clears the LEDs and then tests its memory cache. When
this test starts, the DS and MSG LEDs come on.
7.
The next step tests the BSS uninitialized data area of the DRAM. When this test starts, all LEDs go
off and the LINK, DS, and MSG LEDs come on. If this test succeeds, the OK LED begins blinking,
the DS and MSG LEDs go off, and the US LED goes on.
8.
The final step tests the remaining DRAM. When this test starts, all LEDs go out and then the DS
and US LEDs go on. If this test succeeds, the DS and US LEDs go out, and the LINK and DSNR
LEDs go on. The OK LED continues blinking until the Cisco uBR905 router has loaded the
Cisco IOS image.
Table 4-1 summarizes the self-test failure codes displayed by the LEDs; these patterns appear only
when the OK LED goes off and remains off during boot.
