While trying to run a deployment the artifact distribution stage receives the following error: Failed to download artifact[Artifact[NameOfArtifactType.NameOfArtifactDefinition.ArtifactName_ArtifactVersion'] to retrieve agent [NameOfArtifactRetrievalAgent]
Release Automation v5.x and above.
In this case the artifact retrieval agent was setup to pull the file from an https URL. For this to work the agent needs the certificate for the https site imported into its java keystore. The nolio_all.log file from the artifact retrieval agent confirms the cause and will generate the following error message when it tries to access an https site that it doesn't have a certificate for to establish a proper SSL Handshake:
2018-06-26 10:40:58,617 [ArtifactsHandlers-1] DEBUG (com.nolio.platform.shared.datamodel.Action:167) - Accessing URL [https://yourUrl/path/to/file] with parameters [],
2018-06-26 10:40:58,758 [ArtifactsHandlers-1] ERROR (com.nolio.platform.shared.datamodel.Action:181) - exception caught
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target