Aruba Certified ClearPass Professional (ACCP) is a retired exam. I suppose you intend to take the new HPE Advanced Product Certification - ClearPass exam?
As far as I know there are no study guide for this exam. General knowledge about authentication protocols, PKI and certificates, understanding of how to integrate with Active Directory etc is a good foundation.
Online ClearPass documentation, video series by Herman at YouTube are also good sources of information.
Also check the objectives for the exam.
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Best Regards
Jonas Hammarbäck
MVP Guru, ACEX, ACDX #1600, ACCX #1335, ACX-Network Security
Aranya AB
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