RDF/IMP and IMPX System Management Manual (RDF 1.4+)

Lockstep Operation

HP NonStop RDF/IMP and IMPX System Management Manual—524388-001

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NAME

This attribute must be $ZLSGW. If you specify anything else, the lockstep gateway

stops and you cannot perform lockstep operations. Note that this means you can only

have a single lockstep gateway process running on your primary system.

PROGRAM

This attribute specifies where the RDF gateway object code resides. Typically, that

location is the same volume and subvolume where all of the other RDF software

resides. Note that the object name is LSGO, and that you must fully qualify the name.

For example, you might specify the PROGRAM attribute as $SYSTEM.RDF.LSGO.

STARTUPMSG

This attribute must include the process name of your RDF extractor (for example,

STARTUPMSG "ENABLE $MEXT"). The startup message must also include either

ENABLE or DISABLE as the first parameter. Failure to include either of these

parameters will cause the gateway to stop. Note that the gateway can only

communicate with one extractor. If you have multiple RDF subsystems using the same

node as their primary system, only one of them can execute lockstep operations.

AUTORESTART

This attribute specifies the number of times SCF attempts to restart the gateway

process if it should stop unexpectedly. You should set this attribute to 10.

Disabling Lockstep

To disable lockstep processing:

1. Change ENABLE to DISABLE in the STARTUPMSG attribute script.

2. Manually delete the RDF lockstep gateway process from SCF.

3. Run the changed SCF script.

When SCF restarts the gateway, lockstep processing is disabled. Thus, if your

application calls DOLOCKSTEP, the gateway will return control immediately to the

application without doing lockstep processing.

Disabling lockstep processing is a very useful feature. Suppose that the

communications lines from your RDF primary to your RDF backup systems are down.

In such a case, the extractor cannot send audit data to the backup system, and

lockstep processing will hang until the communications lines are back up and the

extractor resumes sending audit data. This is desired behavior if you really want

lockstep processing. But suppose that the communications lines have been down for

so long that your applications are getting no work done at all. In such a case, you may