Some functions disturbed: Search hangs, creating new page from templates not possible

[OK]

Hi everybody,
unfortunately the search in our Confluence system doesn't work anymore. As soon as you click on the search it hangs in a loading loop.
The same issue, when I want to create a page from a template. (See screenshots)

The following can be seen in the log:

13-Aug-2019 09:32:27.289 SEVERE [http-nio-8090-exec-8] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [dispatcher] in context with path [/synchrony-proxy] threw exception [Request processing failed; nested exception is java.lang.IllegalArgumentException: No converter found for return value of type: class com.atlassian.synchrony.proxy.web.HealthCheckResult] with root cause
java.lang.IllegalArgumentException: No converter found for return value of type: class com.atlassian.synchrony.proxy.web.HealthCheckResult
at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:178)
at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:153)
at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:165)
at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:80)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:126)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:817)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:731)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:968)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:859)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:844)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at com.atlassian.synchrony.proxy.web.SynchronyProxyFilter.doFilter(SynchronyProxyFilter.java:78)
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262)
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:202)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
at org.apache.catalina.valves.StuckThreadDetectionValve.invoke(StuckThreadDetectionValve.java:206)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587)
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)

Confluence version: 6.15.7

Has anyone ever had a similar problem?

[Shannon S]

Hello Onur,

Welcome to Atlassian Community. It's nice to have you!

First, I wanted to let you know that I saw that you raised another ticket for the same issue with our Advocates in the billing and licensing queue. I have closed this case as a duplicate of this thread.

I see you had some concerns that there is no support included with your Starter License, but I wanted to let you know that is not accurate. As a Starter License customer, you are entitled to Community Support according to the Atlassian Support Offerings. 

Community Support includes a team of Atlassian Support Engineers, many of whom have already worked for several years within the Atlassian support organization, or externally, as a Partner or Expert. In addition to the Community Support Team, you may also receive assistance from many Atlassian Experts, AUG leaders, and enthusiasts of our products. I just want to ensure you that we are here and ready to help you with anything you need. 

I hope that clarifies things but do let me know if you have any other questions about that.

Now, in terms of the issue you are experiencing, the error you have included is a result of the following bug:

• CONFSERVER-58522 stdout.log is flooded with Synchrony Healthcheck exceptions

This error can safely be ignored and will be resolved in a feature release of Confluence.  I also believe it may not be related to the issue you are experiencing creating pages.

Could you let us know the following about your problem?

1. Since when did the issue start occurring? Did it begin after a network change, upgrade, or migration? Or perhaps after a specific 3rd party add-on was installed?
2. Are you behind a firewall or proxy? If so, you can try bypassing the proxy and see if the issue persists.
3. Does the issue occur for all users? Does it persist across various browsers, networks, and computers? 
4. Try disabling all add-ons by putting Confluence into Safe Mode. If the issue doesn't happen again then it may be related to one of your add-ons.
5. Please confirm also your Confluence database version and your Java version, for our reference.
6. Lastly, you can tail your Confluence server logs to see exactly which errors show at the same time you are initiating a search or the create page action. 

Thank you for your help!

Regards,

Shannon

[OK]

Problem identified. It was the load balancer.

[Shannon S]

Onur,

Thank you for the update! Glad to hear you were able to resolve it so quickly. :) 

Take care, and have a pleasant rest of your week.

Regards,

Shannon