NetBase for MPE Reference Guide

Chapter 5

5-54

Shadowing With TurboIMAGE Log Files

NetBase also provides the ability to shadow TurboIMAGE log files. The log files can be shadowed

to another log file or they can be used to shadow changes directly into a shadow copy of the

database. This method does not require the NetBase shell to be installed since it does not use the

intercept facility. A separate process known as NBILOG is used to read the transactions from the log

files and pass them to the shadow transport facility. The NBILOG process is controlled via NBCTRL.

The configuration parameter SHADOW - Use IMAGE Log Files must be set to Y to enable this feature.

Master System

NetBase Background Job

Image

Logfile

NBILOG

NBM.IPC

NBEXPORT

User Application

Use the following steps to configure a database to be shadowed using IMAGE logging. In this

example, we are shadowing the BANNER database in DATA.NETBASE. The master copy resides on

SYSA and the shadow copy resides on SYSB.

Method 1: To shadow TurboIMAGE log files into a shadowed database:

1. Configure NetBase to use IMAGE logging. This is done by setting the SHADOW - Use IMAGE

Log Files configuration parameter to Y on the master machine.

2. Add the database log file to NetBase's directory on the master machine: