Catalina Protocol handler start failed

I one server I get the following error in webtop/logs/cataloga.log.
What can be the reason and how to fix it?

11-Sep-2022 11:35:11.909 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service [Catalina]
11-Sep-2022 11:35:11.910 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.5.56
11-Sep-2022 11:35:11.934 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/var/lib/tomcats/webtop/webapps/webtop]
11-Sep-2022 11:35:22.789 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
11-Sep-2022 11:35:28.277 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/var/lib/tomcats/webtop/webapps/webtop] has finished in [16,343] ms
11-Sep-2022 11:35:28.284 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-nio-"]
11-Sep-2022 11:35:28.310 SEVERE [main] org.apache.catalina.core.StandardService.startInternal Failed to start connector [Connector[AJP/1.3-58009]]
	org.apache.catalina.LifecycleException: Protocol handler start failed
		at org.apache.catalina.connector.Connector.startInternal(
		at org.apache.catalina.util.LifecycleBase.start(
		at org.apache.catalina.core.StandardService.startInternal(
		at org.apache.catalina.util.LifecycleBase.start(
		at org.apache.catalina.core.StandardServer.startInternal(
		at org.apache.catalina.util.LifecycleBase.start(
		at org.apache.catalina.startup.Catalina.start(
		at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
		at sun.reflect.NativeMethodAccessorImpl.invoke(
		at sun.reflect.DelegatingMethodAccessorImpl.invoke(
		at java.lang.reflect.Method.invoke(
		at org.apache.catalina.startup.Bootstrap.start(
		at org.apache.catalina.startup.Bootstrap.main(
	Caused by: java.lang.IllegalArgumentException: The AJP Connector is configured with secretRequired="true" but the secret attribute is either null or "". This combination is not valid.
		at org.apache.coyote.ajp.AbstractAjpProtocol.start(
		at org.apache.catalina.connector.Connector.startInternal(
		... 12 more

The reasoning seems to be this:


This error happens because Apache Tomcat 8.5.51 and newer have the secretRequired parameter set to true by default. When secretRequired is true the AJP/1.3 Connector will not start unless the secret attribute is configured to a non-null, non-zero length String.


It is needed to inform a secret on the AJP connector in server.xml and it should match the existing AJP configuration at the proxy level. For reference on this configuration please visit the official mod_proxy_ajp documentation. Keep in mind that this secret password needs to be defined on the reverse proxy (eg. proxypass) as well, and that this option is available in Apache HTTPD since version 2.5. Another potential solution is to disable this requirement by specifying secretRequired="false" on server.xml , however, this is not recommended due to security concerns.

How to fix it exactly? Where do I have to insert the newly secret?
Why doesn’t nethserver install correct files?

cc// @lucag @Amygos , did you face the same problem?