Identifying Startup Problems - Cisco 12404 Installation And Configuration Manual

Identifying Startup Problems

Identifying Startup Problems
Cisco 12404 Internet Router Installation and Configuration Guide
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cause the system to hang and crash. Two 4-character alphanumeric LED displays
at the right of each line card or RP faceplate display status and error messages,
which can aid in troubleshooting.
Startup problems are commonly due to power source or to a card not properly
seated in the backplane. Although an overtemperature condition is unlikely at
initial startup, the environmental monitoring functions are included here because
they also monitor internal voltages.
When you start up the router for the first time, you should observe the startup
sequence. This section contains a description of the normal startup sequence as
follows:
Each card in the system has an MBus module and at least one DC-DC
•
converter. Each MBus module controls the DC-DC converter. The MBus
module receives +5 VDC directly from the power supplies through the
backplane. When the power supply power switches are turned on, each MBus
module boots from an onboard electrically erasable programmable read-only
memory (EEPROM) device. Each MBus module processor reads a set of
identification pins on the card to the backplane connector telling the MBus
module processor what kind of card it is mounted on, which in turn,
determines how the MBus module will function.
The consolidated switch fabric (CSF) containing the system clock,
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immediately powers on.
The MBus module on the RP monitors the progress of the clock and scheduler
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card power on. When the CSF has powered up, the MBus module on the RP
turns on its DC-DC converter powering up the RP.
The RP sends the instructions to each line card to power on. Each line card
•
processor begins to perform its own boot process. Each line card, through its
MBus module, notifies the RP when the boot process is complete.
As the boot process progresses for each card, the card's status is displayed in
•
the alphanumeric LED displays. The left display is powered by the DC-DC
converter on the card; the right display is powered by the +5 VDC that powers
the MBus module.
Chapter 4 Troubleshooting the Installation
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