I was having:
2022-12-07 09:21:25.077 ERROR 25057 --- [nio-8001-exec-4] o.k.adapters.OAuthRequestAuthenticator : failed to turn code into tokenjava.net.ConnectException: Connection timed out (Connection timed out)at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.8.0_352]at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_352]at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_352]at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_352]at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_352]at java.net.Socket.connect(Socket.java:607) ~[na:1.8.0_352]at org.apache.http.conn.ssl.SSLSocketFactory.connectSocket(SSLSocketFactory.java:542) ~[httpclient-4.5.3.jar!/:4.5.3]at org.keycloak.adapters.SniSSLSocketFactory.connectSocket(SniSSLSocketFactory.java:109) ~[keycloak-adapter-core-4.5.0.Final.jar!/:4.5.0.Final]at org.apache.http.conn.ssl.SSLSocketFactory.connectSocket(SSLSocketFactory.java:414) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:180) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:144) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:134) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:610) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:445) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:835) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:83) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:108) ~[httpclient-4.5.3.jar!/:4.5.3]at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:56) ~[httpclient-4.5.3.jar!/:4.5.3]at org.keycloak.adapters.ServerRequest.invokeAccessCodeToToken(ServerRequest.java:111) ~[keycloak-adapter-core-4.5.0.Final.jar!/:4.5.0.Final]at org.keycloak.adapters.OAuthRequestAuthenticator.resolveCode(OAuthRequestAuthenticator.java:335) ~[keycloak-adapter-core-4.5.0.Final.jar!/:4.5.0.Final]at org.keycloak.adapters.OAuthRequestAuthenticator.authenticate(OAuthRequestAuthenticator.java:280) ~[keycloak-adapter-core-4.5.0.Final.jar!/:4.5.0.Final]at org.keycloak.adapters.RequestAuthenticator.authenticate(RequestAuthenticator.java:139) ~[keycloak-adapter-core-4.5.0.Final.jar!/:4.5.0.Final]at org.keycloak.adapters.tomcat.AbstractKeycloakAuthenticatorValve.authenticateInternal(AbstractKeycloakAuthenticatorValve.java:203) ~[keycloak-tomcat-core-adapter-4.5.0.Final.jar!/:4.5.0.Final]at org.keycloak.adapters.tomcat.KeycloakAuthenticatorValve.authenticate(KeycloakAuthenticatorValve.java:50) [keycloak-tomcat8-adapter-4.5.0.Final.jar!/:4.5.0.Final]at org.keycloak.adapters.tomcat.KeycloakAuthenticatorValve.doAuthenticate(KeycloakAuthenticatorValve.java:57) [keycloak-tomcat8-adapter-4.5.0.Final.jar!/:4.5.0.Final]at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:556) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.keycloak.adapters.tomcat.AbstractKeycloakAuthenticatorValve.invoke(AbstractKeycloakAuthenticatorValve.java:181) ~[keycloak-tomcat-core-adapter-4.5.0.Final.jar!/:4.5.0.Final]at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:677) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:798) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1434) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_352]at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_352]at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.11.jar!/:8.5.11]at java.lang.Thread.run(Thread.java:750) [na:1.8.0_352]
Found out that server couldn't curl to keyclock which installed on the same machine by using public domain:
curl https://your.public.keycloak.com
curl: (7) Failed connect to your.public.keycloak.com:443; Connection timed out