IDP OS 5.0 does not support HA. IDP OS 5.1 does support HA. Please take a look at the documentation for the IDP Series HA feature to understand the requirements and limitations and see examples on how to implement HA.
We encourage you to provide feedback, comments, and suggestions so that we can improve the documentation. You can send your comments to firstname.lastname@example.org, or fill out the documentation feedback form.