我正在尝试通过API从站点获取数据。我收到以下错误。
The exception occurred is : 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
我已经下载了证书（Base64编码的.cer格式），并按照here中的步骤添加了它。当我在Windows系统上运行此错误时，此错误已得到解决。但是，当我在CENT OS系统中采用相同的解决方案时，错误仍然存在。
为什么无法在CENT OS中识别证书。对于不同的OS系统，我是否必须以其他方式导入证书。
这里是完整的错误日志。
11:31:42 ERROR CaseManagementController {? ?} - The exception occurred is : 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
at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1946)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:316)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:310)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1639)
at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:223)
at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1037)
at sun.security.ssl.Handshaker.process_record(Handshaker.java:965)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1064)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1367)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1395)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1379)
at org.apache.http.conn.ssl.SSLSocketFactory.createLayeredSocket(SSLSocketFactory.java:573)
at org.apache.http.conn.ssl.SSLSocketFactory.connectSocket(SSLSocketFactory.java:557)
at org.apache.http.conn.ssl.SSLSocketFactory.connectSocket(SSLSocketFactory.java:414)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:180)
at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:326)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:610)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:445)
at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:835)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:83)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:108)
at com.gavs.gavel.controllers.CaseManagementController$$anonfun$getMEServiceDeskPlusPriorityList$1.apply(CaseManagementController.scala:2126)
at com.gavs.gavel.controllers.CaseManagementController$$anonfun$getMEServiceDeskPlusPriorityList$1.apply(CaseManagementController.scala:2103)
at scala.Function1$$anonfun$andThen$1.apply(Function1.scala:52)
at play.api.mvc.ActionBuilderImpl.invokeBlock(Action.scala:482)
at play.api.mvc.ActionBuilderImpl.invokeBlock(Action.scala:480)
at play.api.mvc.ActionBuilder$$anon$2.apply(Action.scala:419)
at play.api.mvc.Action$$anonfun$apply$2.apply(Action.scala:96)
at play.api.mvc.Action$$anonfun$apply$2.apply(Action.scala:89)
at play.api.libs.streams.StrictAccumulator$$anonfun$mapFuture$2$$anonfun$1.apply(Accumulator.scala:174)
at play.api.libs.streams.StrictAccumulator$$anonfun$mapFuture$2$$anonfun$1.apply(Accumulator.scala:174)
at scala.util.Try$.apply(Try.scala:192)
at play.api.libs.streams.StrictAccumulator$$anonfun$mapFuture$2.apply(Accumulator.scala:174)
at play.api.libs.streams.StrictAccumulator$$anonfun$mapFuture$2.apply(Accumulator.scala:170)
at scala.Function1$$anonfun$andThen$1.apply(Function1.scala:52)
at play.api.libs.streams.StrictAccumulator.run(Accumulator.scala:207)
at play.core.server.AkkaHttpServer$$anonfun$15.apply(AkkaHttpServer.scala:337)
at play.core.server.AkkaHttpServer$$anonfun$15.apply(AkkaHttpServer.scala:335)
at akka.http.scaladsl.util.FastFuture$.akka$http$scaladsl$util$FastFuture$$strictTransform$1(FastFuture.scala:41)
at akka.http.scaladsl.util.FastFuture$$anonfun$transformWith$extension1$1.apply(FastFuture.scala:51)
at akka.http.scaladsl.util.FastFuture$$anonfun$transformWith$extension1$1.apply(FastFuture.scala:50)
at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:36)
at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:55)
at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply$mcV$sp(BatchingExecutor.scala:91)
at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
at scala.concurrent.BlockContext$.withBlockContext(BlockContext.scala:72)
at akka.dispatch.BatchingExecutor$BlockableBatch.run(BatchingExecutor.scala:90)
at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:40)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(ForkJoinExecutorConfigurator.scala:43)
at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
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:397)
at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302)
at sun.security.validator.Validator.validate(Validator.java:262)
at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:330)
at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:237)
at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:132)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1621)
... 50 more
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:392)
... 56 more
当我在要尝试访问的站点上尝试'curl'命令时，得到以下信息：
curl: (60) Peer's Certificate issuer is not recognized.
More details here: http://curl.haxx.se/docs/sslcerts.html
curl performs SSL certificate verification by default, using a "bundle"
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn't adequate, you can specify an alternate file
using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
the -k (or --insecure) option.
您还需要从您的CA添加根证书的整个链。您可以检查this page了解更多信息。
证书链是证书的有序列表，其中包含SSL证书和证书颁发机构（CA）证书，使接收者能够验证发送者和所有CA值得信赖。链或路径以SSL证书开头，并且链中的每个证书均由以下实体标识：链中的下一个证书。
位于SSL证书和根之间的任何证书证书称为链证书或中级证书。的中间证书是SSL证书的签名者/发布者。根CA证书是中级的签名者/发行者证书。如果未在证书上安装中间证书服务器（已安装SSL证书的服务器）可能会阻止某些浏览器，移动设备，应用程序等信任SSL证书。为了使SSL证书与所有客户，有必要将中间证书已安装。
该链以根CA证书终止。根CA证书始终由CA自己签名。所有的签名链中的证书必须经过根CA的验证证书。