IBM RedBooks SAN24B-5, Installation, Service And User Manual

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POST includes the following tasks:
v
Conducts preliminary POST diagnostics
v Initializes the operating system
v
Initializes hardware
v Runs diagnostic tests on several functions, including circuitry, port functionality,
memory, statistics counters, and serialization
Boot
In addition to POST, boot includes the following tasks after POST is complete:
v Performs universal port configuration
v
Initializes links
v Analyzes fabric. If any ports are connected to other switches, the switch
participates in a fabric configuration
v
Obtains a domain ID and assigns port addresses
v Constructs unicast routing tables
v
Enables normal port operation
Interpreting POST results
POST is a system check that is performed each time the switch is powered on,
rebooted, or reset. During POST, the LEDs flash either amber or green. Any errors
that occur during POST are listed in the error log.
Complete the following steps to determine whether POST completed successfully
and whether any errors were detected.
1. Verify that the switch LEDs indicate that all components are healthy.
See Table 4 on page 27 and Table 5 on page 28 for descriptions and
interpretations of LED patterns. If one or more LEDs do not display a healthy
state, verify that the LEDs on the switch are not set to “beacon” by entering the
switchShow command to detect if beaconing is active.
2. Verify that the switch prompt displays on the terminal of a computer
workstation connected to the switch.
If there is no switch prompt when POST completes, press
Enter . If the switch
prompt still does not display, try opening a Telnet session or accessing the
switch through another management tool. If this is not successful, the switch
did not successfully complete POST. Contact IBM.
3.
Review the switch system log for errors. Any errors detected during POST are
written to the system log, accessible through the
errShow command.
For information about all referenced commands, and on accessing the error log,
refer to the
Fabric OS Administrator’s Guide . For information about error messages,
refer to the Fabric OS Message Reference Manual .
SAN24B-5 maintenance
The SAN24B-5 is designed for high availability and low failure; it does not require
any regular physical maintenance. It includes diagnostic tests and field-replaceable
units, described in the following sections.
Chapter 3. Using and maintaining the switch
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