IBM SY44-5902-05 manual Working with Storage Dumps, Main storage dump introduction

Chapter 10. Working with Storage Dumps

Main storage dump introduction	.	269	Additional help	.	277
Automatic main storage dump	. 270		Performing an IOP storage dump to disk (Models
Performing a main storage dump to disk (manual			150, 170, 250, 4xx, 50x, 51x, 530, 53S, 6xx, 7xx, SB1,
MSD)	.	271	S20, S30, and S40)	.	277
Copying a main storage dump	. 272		Performing a service processor storage dump
Work with current main storage dump . . .	. 273		(Models 270, 8xx, SB2, SB3, and 890) . . . .	. 277
Display main storage dump	. 274		Copying the IOP storage dump to removable
Copy main storage dump to media . . .	. 274		media (All Models)	. 278
Copy main storage dump to MSD copy .	. 274		Copying the service processor storage dump to
Work with copies of main storage dumps . .	. 274		removable media (Models 270, 8xx, SB2, SB3, and
Main storage dump status	.	275	890)	.	278
Terminating System Reference Code (SRC) .	. 275		Performing an IOP dump using hardware service
Error recovery for dumps	.	276	manager (All Models)	.	279
Determining whether main storage dump data			IOP dump information in the Product Activity Log
was written to disk	.	276	(All Models)	.	279
Reporting the error	.	276

Main storage dump introduction

A main storage dump (MSD) is a process of collecting data from the system’s main storage. A main storage dump can be performed in the following ways:

vAutomatically - by the service processor as the result of a system failure.

vManually - by use of Function 22 on the control panel when the system waits, loops, or appears to have an operating system failure.

For more information on automatic and manual MSDs, see “Automatic main storage dump” on page 270 and “Performing a main storage dump to disk (manual MSD)” on page 271.

A complete MSD consists of the following:

vMain storage data

vLicensed Internal Code (LIC) module information (link map)

vMSD control data (SID 82)

Main storage dump data can be stored in three places:

vOn the load-source disk

All MSD data is stored on the load-source disk during the dump process. While it is on the load-source disk, it is called the current MSD. You can display or copy the current MSD until either the next main storage dump occurs (writes over it), or the next IPL is performed. To ensure that the current MSD is available to assist in problem analysis, you must copy the dump to removable media or the MSD library. Once an IPL occurs, some main storage data for the current MSD may be lost. Also the link map for the current MSD may be inaccurate. What remains of the current MSD is called residue.

vOn removable media

This is a copy of the data that was first stored on the load-source disk, plus a current link map and any MSD data still in main storage. The MSD that is copied to removable media (for example, tape) can assist in problem analysis.

vIn the MSD library

© Copyright IBM Corp. 1997, 2002 269