An Introduction to IMS: Your Complete Guide to IBMs Information Management System

During IMS execution, all information that is necessary to restart the system in the event of hardware or software failure is recorded in a system log data set. The following critical system information is recorded in the logs:

• The receipt of an input message in the input queue

• The start of an MPP or BMP program

• The receipt of a message by the MPP for processing

• Before and after images of data base updates by the MPP or BMP program

• The insert of a message into the queue by the MPP

• The termination of an MPP or BMP program

• The successful receipt of an output message by the terminal

In This Chapter:

• "IMS System Checkpoints"

• "Database Recovery Control Facility (DBRC)" on page 368

• "IMS Log Components" on page 368