SharePlex 11.4 - Administration Guide

SharePlex parameters control and tune various aspects of replication.

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View and Set Parameters

A SharePlex Administrator (defined as a member of the SharePlex Admin group) can change parameters that are designated as user-configurable and is the only user authorized to do so.

View parameters

Use the list param command in sp_ctrl to view user-configurable SharePlex parameters. It displays parameter names, current settings, default values (if the parameter has been changed), and set-at points. The set-at point indicates when changes to a parameter will take effect. Possible set-at points are:

• Live means a change takes effect immediately.
• Restart Process means a change takes effect after the affected SharePlex process is restarted.
• Restart Cop means a change takes effect after sp_cop is restarted.

Additional options are available for viewing:

• All SharePlex parameters.
• Only parameters whose values have changed.
• Parameters relating to a specific SharePlex module.

To view descriptions of the SharePlex parameters, see theSharePlex Reference Guide.

Set parameters

Parameters can be set in the following ways:

• With the set param command through the sp_ctrl interface. This is the preferred method because the new value remains intact no matter how many times replication stops and starts. The syntax is:

  set param parameter_name value

  Example:

• set param SP_OCT_REPLICATE_ALL_DDL 1
• As environment variables on Unix and Linux systems prior to starting sp_cop. The new value remains in effect only for that session of sp_cop.

Parameters for the Capture, Read, Export, Import, and Post processes can be set on a per-process basis when there are multiple instances of a process for an instance of SharePlex.

Set SharePlex parameters through sp_ctrl

The recommended way to change a SharePlex parameter is to use the set param command in sp_ctrl.

To restore a parameter’s setting to its default value, use the reset param command.

To view descriptions of the SharePlex commands, see theSharePlex Reference Guide.

Set SharePlex parameters as environment variables

On Unix and Linux, a SharePlex parameter can be set as an environment variable. The environment variable overrides the setting in the param-defaults files, but only for the session of sp_cop for which it was set. If you shut down sp_cop and restart it without resetting the environment variable, SharePlex uses the default setting in the param-defaults file.

To set a SharePlex parameter as an environment variable on Unix and Linux systems, use one of the following commands. Set the environment variable before starting sp_cop or, if sp_cop is running, restart sp_cop for the new setting to take effect.

Because of the temporary nature of environment variables, avoid using them if possible; instead make your changes with the set param command. When you rely on environment variables, especially when there are multiple users of SharePlex, you incur the risk of someone forgetting to set them (or using an incorrect value) when they restart sp_cop. That can have a significant, negative impact on replication and can result in the need to resynchronize the data.

The following files store SharePlex parameter settings:

• The param-defaults file stores default settings that were set by developers for optimal replication performance under most conditions. The param-defaults file resides in the data sub-directory of the SharePlex product directory. The data in this file does not change unless a new version of SharePlex is installed.

  Important: Never edit this file.

• The paramdb file stores user-defined parameter settings — values that were changed from their defaults by a SharePlex Administrator using the set param command. Also stored in this file are the SharePlex Oracle user and the SharePlex user’s password.

  When users execute the Reset Param command on sp_ctrl, the earlier entry stored in the paramdb gets removed.

  The paramdb resides in the data sub-directory of the SharePlex variable-data directory. It starts out empty, and as SharePlex Administrators change parameter values, those values are added to it. User-defined parameter values override SharePlex default values when SharePlex is running. All of the settings in the paramdb file remain intact when a new version of SharePlex is installed.

SharePlex uses a configuration file to determine which tables to replicate and where to send the replicated data. This file also provides any special processing instructions, such as column mapping and data filtering. This chapter contains the information that you need to know in order to create a configuration file.

Once you understand the basics of how to create a configuration file and route data to your targets, you can move on to any of the more advanced configurations as needed. Documentation for those configurations is included in this guide.

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