PKIX path building failed. unable to find valid certification path to requested target.

[#1]

Hi Team,

When I'm trying put a file in S3 through Nifi Web UI, getting below error.

Whether through Aws CLI, I can copy files to S3 from Nifi servers.

I have updated the cacerts file in below paths

/usr/jdk64/jdk1.8.0_112/jre/lib/security/cacerts

/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre/lib/security/cacerts

Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:387)
        at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292)
        at sun.security.validator.Validator.validate(Validator.java:260)
        at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)
        at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229)
        at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124)
        at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1491)
        ... 50 common frames omitted
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
        at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
        at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:382)
        ... 56 common frames omitted
2018-04-17 01:33:54,624 ERROR [Timer-Driven Process Thread-3] o.a.nifi.processors.aws.s3.PutS3Object PutS3Object[id=9d2034-02b3e9b22] Error checking S3 Multipart Upload list for non-prod-on-prem-dropoff: Unable to execute HTTP request: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
2018-04-17 01:33:54,694 ERROR [Timer-Driven Process Thread-3] o.a.nifi.processors.aws.s3.PutS3Object PutS3Object[id=9d202b3e9b22] Failed to put StandardFlowFileRecord[uuid=be294f52-c,claim=StandardContentClaim [resourceClaim=StandardResourceClaim[id=1523871738280-1, container=default, section=1], offset=50440, length=10088],offset=0,name=test3,size=10088] to Amazon S3 due to com.amazonaws.SdkClientException: Unable to execute HTTP request: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target: {}
com.amazonaws.SdkClientException: Unable to execute HTTP request: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target.

[#2]

@JZ Can you please suggest - as per https://community.hortonworks.com/questions/167502/nifi-ssl-unable-to-find-valid-certification-path-...