Re: [keycloak-user] How to achieve "service continuity" with KeyCloak in Standalone Cluster mode ?

Hi all, I'm trying to deploy KeyCloak (v 4.8.3-final) in Standalone Cluster mode in order to answer a very specific requirement: get continuity of service 1/ in case of crash of a KeyCloak instance, 2/ during the upgrade of my solution. However, I unfortunately don't get such results :(, despite the fact the cluster looks to be properly configured. First, as I'm deploying KeyCloak in Kubernetes, I configured KeyCloak in Standalone Cluster by using the DNS_PING and a TCP transport for JGroups. Instances of the cluster can discover/see each other and the cluster is working fine as soon as it is used a couple of seconds/minutes after starting the instances. I've created a simple script that just get in a loop the JWT tokens using the Token endpoint of a Realm, and I always have a 200 Ok status code whatever the KeyCloak instance that is hit through the Kubernetes Service. However, coming back to the 2 uses cases I'm interested in, it looks the KeyCloak instances are getting crazy as soon as the cluster is not "stable". By "cluster is not stable", I mean: - When scaling down the number of Keycloak instances (whatever it is by killing a Container or by a smart scale down of the Kubernetes Deployment) - When performing a rolling update of the Pods In both cases, during a particular time, most of the calls to get a JWT return a HTTP 499 status code and KeyCloak logs show the following: 08:14:56,785 ERROR [org.infinispan.interceptors.impl.InvocationContextInterceptor] (timeout-thread--p13-t1) ISPN000136: Error executing command GetKeyValueCommand, writing keys ISPN000476: Timed out waiting for responses for request 1883 from id-provider-5c55bbd99d-kqr8v at org.infinispan.remoting.transport.impl.MultiTargetRequest.onTimeout(MultiTargetRequest.java:167) at org.infinispan.remoting.transport.jgroups.StaggeredRequest.onTimeout(StaggeredRequest.java:64) at org.infinispan.remoting.transport.AbstractRequest.call(AbstractRequest.java:87) at org.infinispan.remoting.transport.AbstractRequest.call(AbstractRequest.java:22) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) 08:14:56,790 ERROR [org.keycloak.services.error.KeycloakErrorHandler] (default task-992) Uncaught server error: org.infinispan.util.concurrent.TimeoutException: ISPN000476: Time-provider-5c55bbd99d-kqr8v at org.infinispan.interceptors.impl.AsyncInterceptorChainImpl.invoke(AsyncInterceptorChainImpl.java:259) at org.infinispan.cache.impl.CacheImpl.get(CacheImpl.java:479) at org.infinispan.cache.impl.CacheImpl.get(CacheImpl.java:472) at org.infinispan.cache.impl.AbstractDelegatingCache.get(AbstractDelegatingCache.java:348) at org.infinispan.cache.impl.EncoderCache.get(EncoderCache.java:659) at org.infinispan.cache.impl.AbstractDelegatingCache.get(AbstractDelegatingCache.java:348) at org.keycloak.models.sessions.infinispan.changes.InfinispanChangelogBasedTransaction.get(InfinispanChangelogBasedTransaction.java:120) at org.keycloak.models.sessions.infinispan.InfinispanUserSessionProvider.getLoginFailureEntity(InfinispanUserSessionProvider.java:678) at org.keycloak.models.sessions.infinispan.InfinispanUserSessionProvider.getUserLoginFailure(InfinispanUserSessionProvider.java:672) at org.keycloak.services.managers.DefaultBruteForceProtector.isTemporarilyDisabled(DefaultBruteForceProtector.java:306) at org.keycloak.authentication.authenticators.directgrant.ValidateUsername.authenticate(ValidateUsername.java:85) at org.keycloak.authentication.DefaultAuthenticationFlow.processFlow(DefaultAuthenticationFlow.java:221) at org.keycloak.authentication.DefaultAuthenticationFlow.processFlow(DefaultAuthenticationFlow.java:148) at org.keycloak.authentication.AuthenticationProcessor.authenticateOnly(AuthenticationProcessor.java:910) at org.keycloak.protocol.oidc.endpoints.TokenEndpoint.resourceOwnerPasswordCredentialsGrant(TokenEndpoint.java:554) at org.keycloak.protocol.oidc.endpoints.TokenEndpoint.processGrantRequest(TokenEndpoint.java:187) at sun.reflect.GeneratedMethodAccessor449.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:140) at org.jboss.resteasy.core.ResourceMethodInvoker.internalInvokeOnTarget(ResourceMethodInvoker.java:509) at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTargetAfterFilter(ResourceMethodInvoker.java:399) at org.jboss.resteasy.core.ResourceMethodInvoker.lambda$invokeOnTarget$0(ResourceMethodInvoker.java:363) at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:358) at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:365) at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:337) at org.jboss.resteasy.core.ResourceLocatorInvoker.invokeOnTargetObject(ResourceLocatorInvoker.java:137) at org.jboss.resteasy.core.ResourceLocatorInvoker.invoke(ResourceLocatorInvoker.java:106) at org.jboss.resteasy.core.ResourceLocatorInvoker.invokeOnTargetObject(ResourceLocatorInvoker.java:132) at org.jboss.resteasy.core.ResourceLocatorInvoker.invoke(ResourceLocatorInvoker.java:100) at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:443) at org.jboss.resteasy.core.SynchronousDispatcher.lambda$invoke$4(SynchronousDispatcher.java:233) at org.jboss.resteasy.core.SynchronousDispatcher.lambda$preprocess$0(SynchronousDispatcher.java:139) at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:358) at org.jboss.resteasy.core.SynchronousDispatcher.preprocess(SynchronousDispatcher.java:142) at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:219) at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:227) at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56) at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51) at javax.servlet.http.HttpServlet.service(HttpServlet.java:791) at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:74) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:129) at org.keycloak.services.filters.KeycloakSessionServletFilter.doFilter(KeycloakSessionServletFilter.java:90) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84) at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) at io.undertow.servlet.handlers.ServletChain$1.handleRequest(ServletChain.java:68) at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:132) at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50) at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at org.wildfly.extension.undertow.deployment.GlobalRequestControllerHandler.handleRequest(GlobalRequestControllerHandler.java:68) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292) at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135) at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) at org.wildfly.extension.undertow.security.SecurityContextThreadSetupAction.lambda$create$0(SecurityContextThreadSetupAction.java:105) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272) at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81) at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104) at io.undertow.server.Connectors.executeRootHandler(Connectors.java:360) at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:830) at org.jboss.threads.ContextClassLoaderSavingRunnable.run(ContextClassLoaderSavingRunnable.java:35) at org.jboss.threads.EnhancedQueueExecutor.safeRun(EnhancedQueueExecutor.java:1985) at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.doRunTask(EnhancedQueueExecutor.java:1487) at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1378) at java.lang.Thread.run(Thread.java:748) Caused by: org.infinispan.util.concurrent.TimeoutException: ISPN000476: Timed out waiting for responses for request 1883 from id-provider-5c55bbd99d-kqr8v at org.infinispan.remoting.transport.impl.MultiTargetRequest.onTimeout(MultiTargetRequest.java:167) at org.infinispan.remoting.transport.jgroups.StaggeredRequest.onTimeout(StaggeredRequest.java:64) at org.infinispan.remoting.transport.AbstractRequest.call(AbstractRequest.java:87) at org.infinispan.remoting.transport.AbstractRequest.call(AbstractRequest.java:22) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ... 1 more Suppressed: org.infinispan.util.logging.TraceException at org.infinispan.interceptors.impl.SimpleAsyncInvocationStage.get(SimpleAsyncInvocationStage.java:41) at org.infinispan.interceptors.impl.AsyncInterceptorChainImpl.invoke(AsyncInterceptorChainImpl.java:250) at org.infinispan.cache.impl.CacheImpl.get(CacheImpl.java:479) at org.infinispan.cache.impl.CacheImpl.get(CacheImpl.java:472) at org.infinispan.cache.impl.AbstractDelegatingCache.get(AbstractDelegatingCache.java:348) at org.infinispan.cache.impl.EncoderCache.get(EncoderCache.java:659) at org.infinispan.cache.impl.AbstractDelegatingCache.get(AbstractDelegatingCache.java:348) at org.keycloak.models.sessions.infinispan.changes.InfinispanChangelogBasedTransaction.get(InfinispanChangelogBasedTransaction.java:120) at org.keycloak.models.sessions.infinispan.InfinispanUserSessionProvider.getLoginFailureEntity(InfinispanUserSessionProvider.java:678) at org.keycloak.models.sessions.infinispan.InfinispanUserSessionProvider.getUserLoginFailure(InfinispanUserSessionProvider.java:672) at org.keycloak.services.managers.DefaultBruteForceProtector.isTemporarilyDisabled(DefaultBruteForceProtector.java:306) at org.keycloak.authentication.authenticators.directgrant.ValidateUsername.authenticate(ValidateUsername.java:85) at org.keycloak.authentication.DefaultAuthenticationFlow.processFlow(DefaultAuthenticationFlow.java:221) at org.keycloak.authentication.DefaultAuthenticationFlow.processFlow(DefaultAuthenticationFlow.java:148) at org.keycloak.authentication.AuthenticationProcessor.authenticateOnly(AuthenticationProcessor.java:910) at org.keycloak.protocol.oidc.endpoints.TokenEndpoint.resourceOwnerPasswordCredentialsGrant(TokenEndpoint.java:554) at org.keycloak.protocol.oidc.endpoints.TokenEndpoint.processGrantRequest(TokenEndpoint.java:187) at sun.reflect.GeneratedMethodAccessor449.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:140) at org.jboss.resteasy.core.ResourceMethodInvoker.internalInvokeOnTarget(ResourceMethodInvoker.java:509) at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTargetAfterFilter(ResourceMethodInvoker.java:399) at org.jboss.resteasy.core.ResourceMethodInvoker.lambda$invokeOnTarget$0(ResourceMethodInvoker.java:363) at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:358) at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:365) at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:337) at org.jboss.resteasy.core.ResourceLocatorInvoker.invokeOnTargetObject(ResourceLocatorInvoker.java:137) at org.jboss.resteasy.core.ResourceLocatorInvoker.invoke(ResourceLocatorInvoker.java:106) at org.jboss.resteasy.core.ResourceLocatorInvoker.invokeOnTargetObject(ResourceLocatorInvoker.java:132) at org.jboss.resteasy.core.ResourceLocatorInvoker.invoke(ResourceLocatorInvoker.java:100) at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:443) at org.jboss.resteasy.core.SynchronousDispatcher.lambda$invoke$4(SynchronousDispatcher.java:233) at org.jboss.resteasy.core.SynchronousDispatcher.lambda$preprocess$0(SynchronousDispatcher.java:139) at org.jboss.resteasy.core.interception.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:358) at org.jboss.resteasy.core.SynchronousDispatcher.preprocess(SynchronousDispatcher.java:142) at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:219) at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:227) at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56) at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51) at javax.servlet.http.HttpServlet.service(HttpServlet.java:791) at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:74) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:129) at org.keycloak.services.filters.KeycloakSessionServletFilter.doFilter(KeycloakSessionServletFilter.java:90) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84) at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) at io.undertow.servlet.handlers.ServletChain$1.handleRequest(ServletChain.java:68) at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:132) at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50) at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at org.wildfly.extension.undertow.deployment.GlobalRequestControllerHandler.handleRequest(GlobalRequestControllerHandler.java:68) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292) at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135) at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) at org.wildfly.extension.undertow.security.SecurityContextThreadSetupAction.lambda$create$0(SecurityContextThreadSetupAction.java:105) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1502) at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272) at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81) at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104) at io.undertow.server.Connectors.executeRootHandler(Connectors.java:360) at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:830) at org.jboss.threads.ContextClassLoaderSavingRunnable.run(ContextClassLoaderSavingRunnable.java:35) at org.jboss.threads.EnhancedQueueExecutor.safeRun(EnhancedQueueExecutor.java:1985) at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.doRunTask(EnhancedQueueExecutor.java:1487) at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1378) ... 1 more It looks that the KeyCloak instances that is still alive and receiving the call for generation of the JWT is trying to contact the other instances in order to get some data from the distributed cache... In particular, it tries to contact the instance that is no longer here (because killed, shutdown, rolled...), received a Timeout error, and then terminates the incoming request in error. As I'm making the same request within a loop, I see the error happening during a couple of seconds (around 10 to 15 secs), i.e. during the time the cluster composition is not stabilized yet. When the re-discovery of the cluster has been performed, the new composition of the cluster is updated, and everything goes back to normal! I can understand, from KeyCloak documentation on server caches (https://www.keycloak.org/docs/4.8/server_installation/index.html#_replica...) that "By default, Keycloak only specifies one owner for data. So if that one node goes down that data is lost. This usually means that users will be logged out and will have to login again. You can change the number of nodes that replicate a piece of data by change the owners attribute in the distributed-cache declaration.", but unfortunately, setting the "owner" field to 2 (or more !) for all distributed caches does not remove the issue. I even tried to change the type of cache from "distributed-cache" to "replicated-cache", but then KeyCloak is not starting: <replicated-cache name="sessions"/> <replicated-cache name="authenticationSessions"/> <replicated-cache name="offlineSessions"/> <replicated-cache name="clientSessions"/> <replicated-cache name="offlineClientSessions"/> <replicated-cache name="loginFailures"/> <replicated-cache name="actionTokens"> <object-memory size="-1"/> <expiration interval="300000" max-idle="-1"/> </replicated-cache> Error during startup: 15:07:13,942 ERROR [org.infinispan.topology.LocalTopologyManagerImpl] (transport-thread--p14-t10) ISPN000230: Failed to start rebalance for cache authenticationSessions: java.lang.ClassCastException: org.infinispan.distribution.ch.impl.DefaultConsistentHash cannot be cast to org.infinispan.distribution.ch.impl.ReplicatedConsistentHash at org.infinispan.distribution.ch.impl.SyncReplicatedConsistentHashFactory.union(SyncReplicatedConsistentHashFactory.java:26) at org.infinispan.topology.LocalTopologyManagerImpl.doHandleRebalance(LocalTopologyManagerImpl.java:512) at org.infinispan.topology.LocalTopologyManagerImpl.lambda$handleRebalance$3(LocalTopologyManagerImpl.java:475) at org.infinispan.executors.LimitedExecutor.runTasks(LimitedExecutor.java:175) at org.infinispan.executors.LimitedExecutor.access$100(LimitedExecutor.java:37) at org.infinispan.executors.LimitedExecutor$Runner.run(LimitedExecutor.java:227) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.wildfly.clustering.service.concurrent.ClassLoaderThreadFactory.lambda$newThread$0(ClassLoaderThreadFactory.java:47) at java.lang.Thread.run(Thread.java:748) Did I forgot one thing? How to get a real continuity of service with KeyCloak? Is Standalone Cluster mode the good way, and how? Thanks a lot for your help. Patrice ________________________________ This message and any attachments are intended solely for the addressees and may contain confidential information. Any unauthorized use or disclosure, either whole or partial, is prohibited. E-mails are susceptible to alteration. Our company shall not be liable for the message if altered, changed or falsified. If you are not the intended recipient of this message, please delete it and notify the sender. Although all reasonable efforts have been made to keep this transmission free from viruses, the sender will not be liable for damages caused by a transmitted virus. _______________________________________________ keycloak-user mailing list keycloak-user(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/keycloak-user