HP-UX System Administrator's Guide: Overview

NOTE: It is possible to analyze a crash dump directly from dump devices using a

debugger that supports this feature

. But, if you need to save it to removable media or

send it to someone you will first need to copy the memory image to the HP-UX file

system area.

For More Information on Defining Dump Devices

The following resources have additional information on defining dump devices:

• The manpage crashconf(1M) describes the primary command used to configure

crash dumps.

• The manpage savecrash(1M) describes the various options for saving crash dumps

to a file system area for later analysis or archiving.

• The manpage crashutil(1M) describes the utility for converting crash dumps into

various formats for later analysis. Similar to savecrash, crashutil can also be

used to retrieve crash dump information from raw dump devices into the HP-UX

file system area.

• The HP-UX System Administrator's Guide: Routine Management Tasks (Chapter 2:

Booting and Shutdown) has a list of additional relevant manpages in the

Configuring Dump Devices section.

What Happens When the System Crashes

An HP-UX system crash (system panic) is an unusual event. When a panic occurs, it

means that HP-UX encountered a condition that it did not know how to handle (or

could not handle). Sometimes you know right away what caused the crash. Other times

the cause is not readily apparent. It is for this reason that HP-UX is equipped with a

dump procedure to capture the contents of memory at the time of the crash for later

analysis.

You define in advance:

• Where you want memory contents dumped (dump devices)

• Whether or not you want the dump to be compressed to save space on your dump

devices (dump compression)

• Whether or not to dump to multiple devices in parallel to save time, allowing

(dump concurrency)

7. Analyzing crash dumps is not a trivial task. It requires intimate knowledge of HP-UX internal structures

and the use of debuggers. It is beyond the scope of this document to cover the actual analysis process.

If you need help analyzing a crash dump, contact your HP representative.

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