Problem Solving with Subsystems
Cisco AS5800 Universal Access Server Hardware Installation Guide5-2
Problem Solving with Subsystems
The key to problem solving is isolating the problem to a specif ic subsyst em. The fi rst step in solving
startup problems is to compare what the system is doing to what it should be doing. T r y to isolate
the problem to one of the following three router shelf or dial shelf subsystems:
•Power
•Cooling
•Processor
Start by checking the rout er sh elf p ower co mponent s. If the pro blem does n ot se em t o orig inat e the re,
check the dial shelf power components.
Router shelf power components include the following:
•AC-input or DC-input power supplies
•Cisco7206 router shelf midplane
•External-power cable connection
Dial shelf power components include the following:
•Power-entry modules (PEMs)
•Filter module
•AC-input power shelf
•Cisco5814 dial shelf backplane
•External-power cable connection
•External monitor syst em
Next, check the router shelf cooling components. If the problem does not seem to origi nate there,
check the dial shelf cooling components. Router shelf and dial shelf fans should all be operating
whenever system power is o n .
•Router shelf cooling components include the fan tray.
•Dial shelf cooling components include the blower assembly.
Last, check the router shelf p roc essor cards. If the problem doe s no t see m to originate there, check
the dial shelf processor cards .
Most processor cards contain LEDs that indicate the status of the card. Observing these LEDs can
help you isolate the problem to a particular card. (See Chapter4, “Powering On the CiscoAS5800
and Observing Initial Startup Conditions,” for LED descriptions and troubleshooting tips.)
The system memory and management functions reside on the router shelf I/O control ler card and the
network processor card. The enabled LED on each port adapter lights when the port adapter is
initialized. A port adapter that is partially plugged into the midplane can cause the system to hang
and crash.
The router shelf processor subsystem includes the following:
•I/O controller card
•Network processor card
•Dial shelf interconnect po rt ad ap t er
•Other port adapters