Hi, i have upgrade to 6.2, server and client works fine. The web interface can be loaded

here the error

[2026-07-01 17:50:14] [crit] One or more listeners failed to start. Full details will be found in the appropriate container log file
[2026-07-01 17:50:14] [crit] Context [/nxmc-6.2.0] startup failed due to previous errors
[2026-07-01 17:50:14] [warning] Failed to clear soft references from ObjectStreamClass$Caches for web application [nxmc-6.2.0]
[2026-07-01 17:50:14] [warning] java.lang.ClassCastException: class java.io.ObjectStreamClass$Caches$1 cannot be cast to class java.util.Map (java.io.ObjectStreamClass$Caches$1 and java.util.Map are in module java.base of loader 'bootstrap')
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.loader.WebappClassLoaderBase.clearCache(WebappClassLoaderBase.java:2325)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesObjectStreamClassCaches(WebappClassLoaderBase.java:2300)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.loader.WebappClassLoaderBase.clearReferences(WebappClassLoaderBase.java:1669)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.loader.WebappClassLoaderBase.stop(WebappClassLoaderBase.java:1597)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.loader.WebappLoader.stopInternal(WebappLoader.java:463)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:257)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5515)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:257)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:187)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.manager.ManagerServlet.start(ManagerServlet.java:1437)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.manager.HTMLManagerServlet.start(HTMLManagerServlet.java:703)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.manager.HTMLManagerServlet.doPost(HTMLManagerServlet.java:221)
[2026-07-01 17:50:14] [warning]     at javax.servlet.http.HttpServlet.service(HttpServlet.java:681)
[2026-07-01 17:50:14] [warning]     at javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.filters.CsrfPreventionFilter.doFilter(CsrfPreventionFilter.java:211)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
[2026-07-01 17:50:14] [warning]     at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.filters.HttpHeaderSecurityFilter.doFilter(HttpHeaderSecurityFilter.java:126)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:659)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:687)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
[2026-07-01 17:50:14] [warning]     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:359)
[2026-07-01 17:50:14] [warning]     at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)
[2026-07-01 17:50:14] [warning]     at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
[2026-07-01 17:50:14] [warning]     at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:889)
[2026-07-01 17:50:14] [warning]     at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1735)
[2026-07-01 17:50:14] [warning]     at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
[2026-07-01 17:50:14] [warning]     at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
[2026-07-01 17:50:14] [warning]     at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
[2026-07-01 17:50:14] [warning]     at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
[2026-07-01 17:50:14] [warning]     at java.base/java.lang.Thread.run(Thread.java:1583)

Apache Tomcat/9.0.58 (Ubuntu)   21.0.11+10-1-22.04.2-Ubuntu

i had the problem with openjdk 17, i have updated to openjdk 21 but same result

can you help?

Hi,

The problem is the servlet container version, not Java.

The NetXMS 6.2 web client (nxmc-6.2.0.war) is built against the Jakarta Servlet API (jakarta.servlet.* namespace) and requires a container that supports it. You are running Tomcat 9.0.58, which still uses the older javax.servlet.* namespace. Because of that, Tomcat 9 cannot load the application's context listeners, which is exactly the "One or more listeners failed to start" / "Context startup failed" error you see.

The ClassCastException about ObjectStreamClass$Caches is a harmless secondary warning. It comes from Tomcat's cleanup routine running on a newer JDK while it tears down the already-failed context - it is not the cause. That is also why switching from JDK 17 to 21 made no difference; the JDK was never the issue.

To fix it, deploy the WAR on a container that supports the Jakarta Servlet API:

- Tomcat 10.1 or later - on Ubuntu use the tomcat10 package, webapps directory /var/lib/tomcat10/webapps.
- Jetty 11 or later is also fine (Jetty 11/12 support the Jakarta Servlet API).

Java 17 or 21 works with either. Do not run it under Tomcat 9 - the javax vs jakarta namespace difference cannot be bridged by a config change or a different JDK.