Authentication request failed: net.sf.acegisecurity.AuthenticationServiceException: sun.security.validator.ValidatorException: PKIX path building fail

CAS can be major pain to set up if you miss some not well documented steps. The major problem with the internet is in general that you have overwhelming mass of poor quality information accessible which covers the real stuff.

Problem:

Authentication request failed: net.sf.acegisecurity.AuthenticationServiceException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target.

Solution:

"A very common mistake in SSL is certificate CN mismatching. Make sure you use the same hostname used in the CN field of the certificate."