Team, we have 6.8.4 setup and we are moving to 7.4.2.
we have slack and email alerts configured. email alerts are working fine. whoever slack alerts are not working. attached is the error and elasticsearch.yml file. this took place after following the steps mentioned in 7.x upgrade wizard. getting below error
[2019-11-09T15:31:26,078][ERROR][o.e.x.w.n.s.SlackService ] [Hotdata-node-10.130.0.53] failed to execute slack api http request
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.SSLConnectionSocketFactory.createLayeredSocket(SSLConnectionSocketFactory.java:394) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.conn.ssl.SSLConnectionSocketFactory.connectSocket(SSLConnectionSocketFactory.java:353) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:141) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:353) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:380) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:236) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:184) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:88) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184) ~[httpclient-4.5.2.jar:4.5.2]
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82) ~[httpclient-4.5.2.jar:4.5.2]
at org.elasticsearch.xpack.watcher.common.http.HttpClient.lambda$execute$0(HttpClient.java:175) ~[?:?]
at java.security.AccessController.doPrivileged(Native Method) ~[?:1.8.0_222]
at org.elasticsearch.xpack.core.common.socket.SocketAccess.doPrivileged(SocketAccess.java:32) ~[x-pack-core-6.8.4.jar:6.8.4]
at org.elasticsearch.xpack.watcher.common.http.HttpClient.execute(HttpClient.java:175) ~[?:?]
at org.elasticsearch.xpack.watcher.notification.slack.SlackAccount.send(SlackAccount.java:115) ~[?:?]
at org.elasticsearch.xpack.watcher.notification.slack.SlackAccount.send(SlackAccount.java:69) ~[?:?]
at org.elasticsearch.xpack.watcher.actions.slack.ExecutableSlackAction.execute(ExecutableSlackAction.java:50) ~[?:?]
at org.elasticsearch.xpack.core.watcher.actions.ActionWrapper.execute(ActionWrapper.java:144) ~[x-pack-core-6.8.4.jar:6.8.4]
at org.elasticsearch.xpack.watcher.execution.ExecutionService.executeInner(ExecutionService.java:526) ~[x-pack-watcher-6.8.4.jar:6.8.4]
at org.elasticsearch.xpack.watcher.execution.ExecutionService.execute(ExecutionService.java:308) ~[x-pack-watcher-6.8.4.jar:6.8.4]
at org.elasticsearch.xpack.watcher.execution.ExecutionService.lambda$executeAsync$5(ExecutionService.java:414) ~[x-pack-watcher-6.8.4.jar:6.8.4]
at org.elasticsearch.xpack.watcher.execution.ExecutionService$WatchExecutionTask.run(ExecutionService.java:615) [x-pack-watcher-6.8.4.jar:6.8.4]
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingRunnable.run(ThreadContext.java:681) [elasticsearch-6.8.4.jar:6.8.4]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_222]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_222]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_222]
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) ~[?:?]
... 34 more