3com S24x Manual De Usuario

3-24 

PathBuilder S24x, 26x, and 27x Switch Hardware Installation

Diagnostics run when a node is powered up. Basic tests are run from PROM and 
more extensive diagnostics are run during startup. 

If the node detects a lack of software, it sends a message to the CTP. The yellow LED 
lights and a 2-digit code is displayed. You must initiate a software coldload if 
needed. 

This is the power-up sequence.

The three types of restarts are:

• Coldstart

• Warmstart

• Default Node

A node coldstart is similar to a power-up. It follows the power-up sequence except 
that it is initiated when the operator presses the RESET button on the front panel or 
when certain software faults occur. All calls are cleared along with Event queues. A 
Node coldstart loads only configuration memory.

A node warmstart can be initiated by a software fault or an operator command. It is 
identical to a coldstart except for the following:

• No diagnostic testing is performed.

• Code downloads are not performed unless necessary.

• Event logs are not erased.

ROM-based diagnostics

Local core self-tests. Boots PROM 
checksum, MPU test, Program RAM test.

FLASH verification

Checksum FLASH image.

Loads RAM diagnostics

Uncompresses FLASH diagnostics image 
to RAM and executes.

RAM-based diagnostics

Tests I/O cards and everything else on card.

Loads RAM operational 
software

Uncompresses FLASH operational 
software image to RAM and executes.

Verifies Config database 

Verifies resident CMEM database.