NetBase for MPE Reference Guide

Welcome to NetBase
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How Does NetBase Work?
NetBase works by intercepting and looking at all calls and file requests to the file system. Requests
to local files are passed directly to MPE to be executed locally, while requests to remote files are
passed by NetBase to the appropriate computer where the file resides. To determine where a
particular file exists, NetBase uses its own directory. The directory is the key to the simplicity of
NetBase implementation.
Specifying the location of networked files is accomplished using the NetBase NBDIR utility program.
To distribute a file or database on the network, you enter the file or database name and its location
in the NetBase directory. A one-line command is all that is required to redirect access to a file or
database. Directory changes take effect immediately, and affect all subsequent access to the file.
Locally accessed files do not need to be entered into the directory.
The following discussions are of each of the NetBase services.
NetBase Shadowing
Integrated into NetBase is the ability to maintain concurrent multiple copies of files and databases.
Keeping multiple copies of data can be useful for a variety of reasons. A local copy of production
data can dramatically reduce I/O contention against the master copy. The production system can
remain online 24 hours a day if shadowed copies of files and databases are used for backup.
Disaster recovery is greatly simplified when current up-to-date copies are always ready in the event
of a disaster.
Master System
Shadow System
On-line users
Read only access
Master Copy
Master Copy
of Data
of Data
Shadow Copy
Shadow Copy
of Data
of Data