Calculating database connections required by CDC Replication Engine for Event Server

As an administrator, you may find it necessary to calculate how many database connections are needed before installing CDC Replication on either a source or a target database. Calculating the upper bound (both permanent and temporary) database connections will help you plan your environment so that it can accommodate CDC Replication.

If you are installing the CDC Replication Engine for InfoSphere® DataStage® or the CDC Replication Engine for Netezza® Technology, then you only need to calculate database connections for the target database as this product only replicate to target-only destinations.

This topic includes the formulae and examples to help you calculate the number of connections required by CDC Replication.

Calculating connections required by CDC Replication on a target database

(4+G)*I + 3*S

Where:

  • G = number of Management Console GUI and CHCCLP scripting applications that are connected to your instances of CDC Replication.
  • I = number of CDC Replication instances.
  • S = number of subscriptions in all of your CDC Replication instances.

Example: How to calculate required connections for a target database

You want to set up CDC Replication in the target environment as follows:
  • 1 installed Management Console GUI application.
  • 2 CDC Replication instances.
  • 3 subscriptions.

The number of connections required on the target database will be:

(4 + 1)*2 + 3*3 = 19

You should plan for a maximum of 19 database connections before installing CDC Replication on the target database.