About System Error States - Sun Microsystems Sun Fire V440 Diagnostics And Troubleshooting Manual

About System Error States

When troubleshooting, it is important to understand what kind of error has
occurred, to distinguish between real and apparent system hangs, and to respond
appropriately to error conditions so as to preserve valuable information.
Responding to System Error States
Depending on the severity of a system error, a Sun Fire V440 server might or might
not respond to commands you issue to the system. Once you have gathered all
available information, you can begin taking action. Your actions depend on the
information you have already gathered and the state of the system.
Guidelines to remember:
Avoid power cycling the system until you have gathered all the information you
can. Error information might be lost when power cycling the system.
If your system appears to be hung, attempt multiple approaches to get the system
to respond. See "Responding to System Hang States" on page 123.
Responding to System Hang States
Troubleshooting a hanging system can be a difficult process because the root cause
of the hang might be masked by false error indications from another part of the
system. Therefore, it is important that you carefully examine all the information
sources available to you before you attempt any remedy. Also, it is helpful to
understand the type of hang the system is experiencing. This hang state information
is especially important to Sun support services engineers, should you contact them.
A system soft hang can be characterized by any of the following symptoms:
Usability or performance of the system gradually decreases.
New attempts to access the system fail.
Some parts of the system appear to stop responding.
You can drop the system into the OpenBoot ok prompt level.
Some soft hangs might dissipate on their own, while others will require that the
system be interrupted to gather information at the OpenBoot prompt level. A soft
hang should respond to a break signal that is sent via the system console.
Chapter 7 Troubleshooting Hardware Problems 123