Problem with Websockets

Hi,

I'm using Ubuntu 16.04

java version "1.8.0_181"
Java(TM) SE Runtime Environment (build 1.8.0_181-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.181-b13, mixed mode)

Recently I upgraded TC Server to 2017.2.4

Previously had 10.0.3 version and web sockets worked correctly.

Now I get such an error:

Any idea what it might be?

[http-nio-8111-exec-14] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [buildServer] in context with path [] threw exception [Filter execution threw an exception] with root cause
 java.lang.NoClassDefFoundError: org/apache/tomcat/websocket/server/WsHttpUpgradeHandler
 at org.apache.tomcat.websocket.server.UpgradeUtil.doUpgrade(UpgradeUtil.java:238)
 at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:77)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
 at jetbrains.buildServer.web.jsp.JspPrecompilerFilter.doFilter(JspPrecompilerFilter.java:26)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
 at jetbrains.buildServer.web.DisableSessionIdFromUrlFilter.doFilter(DisableSessionIdFromUrlFilter.java:9)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
 at jetbrains.buildServer.push.impl.jsr356.WebSocketHandshakeValidationFilter.doFilter(WebSocketHandshakeValidationFilter.java:23)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
 at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:107)
 at jetbrains.buildServer.diagnostic.web.DiagnosticFilter.doFilter(DiagnosticFilter.java:15)
 at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:112)
 at jetbrains.buildServer.web.DependencyParametersCalculationContextFilter.doFilter(DependencyParametersCalculationContextFilter.java:7)
 at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:112)
 at jetbrains.buildServer.web.ContentSecurityPolicyFilter.doFilter(ContentSecurityPolicyFilter.java:14)
 at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:112)
 at jetbrains.buildServer.web.CSRFFilter.doFilter(CSRFFilter.java:100)
 at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:112)
 at org.springframework.web.filter.CompositeFilter.doFilter(CompositeFilter.java:73)
 at jetbrains.buildServer.web.DelegatingFilter.doFilter(DelegatingFilter.java:53)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
 at jetbrains.buildServer.web.ResponseFragmentFilter.doFilter(ResponseFragmentFilter.java:13)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
 at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)
 at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
 at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
 at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
 at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
 at java.lang.Thread.run(Thread.java:748)