What Are the Prerequisites for Adding a New CDC Source to HVR?

Question

What are the prerequisites for adding a new CDC source (a database or data system where changes are monitored and captured using the Change Data Capture mechanism) to HVR?

Environment

HVR 6

Answer

To successfully add a new CDC source to HVR, we recommend that you do the following:

1. Make a note of the host, name, and port of the database you want to connect to.
2. Choose between using the HVR Agent or an agent-less connection method.
3. Select a log reading method based on the connection method.

   NOTE: The log reading method DIRECT requires the use of an HVR Agent.

4. Ensure that the necessary ports (HVR Agent listener port for Agent connections or the database port) are open from the HVR Hub to the source database.

   NOTE: The HVR Hub always initiates the connection.

5. Verify that the database user has the required privileges, including the ability to execute SELECT statements on all tables involved in the replication process. . For more information, see our Source and Target Requirements documentation.
6. Adjust the database's archive log retention policy to retain log files for at least 24 hours. If you store logs externally, such as with Backint, ensure that log files less than 24 hours old are not deleted from storage and that HVR can access them without missing log sequences in the chain.
7. For capture configured in the Archive Log-Only (ALO) mode, minimize latency during off-peak hours by setting a maximum time delay for log switches in your database settings. In addition, assess and adjust the target log file size as needed.
8. Enable supplemental logging or its equivalent at the instance level, if applicable.
9. Enable supplemental logging or its equivalent at the table level, if required.