Installation of EPICS archiver on a single Centos7 machine

[Andrea Celentano via Tech-talk <tech-talk at aps.anl.gov>]

Dear colleagues,

I am currently developing the slow-controls system for a small-scale 
experiment (~ 100 PVs), and I'd like to use the EPICS archiver to 
properly track them.
I am using the following setup:

* Centos7 machine (I cannot change this at the moment)

* Java JDK version 16.0.2

* Archiver release 2.0.5 
(https://urldefense.us/v3/__https://github.com/archiver-appliance/epicsarchiverap/releases/tag/2.0.5__;!!G_uCfscf7eWS!dfP3pgsViV5i5uqOcqz-MWHrFko78Ypy28FydNixfzs_o8UBmRRyBJPjpqZGCwptaFyl7HX0PwxiW6n-WE7VLlepoB0sdgprJNw$ )
* Tomcat version apache-tomcat-9.0.20

* mysql connector version 5.1.21

Following the guide 
(https://urldefense.us/v3/__https://epicsarchiver.readthedocs.io/en/latest/sysadmin/installguide.html__;!!G_uCfscf7eWS!dfP3pgsViV5i5uqOcqz-MWHrFko78Ypy28FydNixfzs_o8UBmRRyBJPjpqZGCwptaFyl7HX0PwxiW6n-WE7VLlepoB0seOqUtEE$ ), 
I am using the script "single_machine_install.sh". Everything goes well, 
I obtain the script "sampleStartup.sh" in the folder where Tomcat 
Instances are located.
If I execute it, and then I open the file "mgmt/logs/catalina.err", I 
see the following error. and the archiver does not start.
...

java.sql.SQLException: Unable to load class: com.mysql.jdbc.Driver from 
ClassLoader:java.net.URLClassLoader@4617c264;ClassLoader:ParallelWebappClassLoader
  context: mgmt
  delegate: false
----------> Parent Classloader:
java.net.URLClassLoader@4617c264

    at 
org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:292)
    at 
org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:212)
    at 
org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:744)
    at 
org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:676)
    at 
org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:483)
    at 
org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154)
    at 
org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118)
    at 
org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107)
    at 
org.apache.tomcat.jdbc.pool.DataSourceFactory.createDataSource(DataSourceFactory.java:560)
    at 
org.apache.tomcat.jdbc.pool.DataSourceFactory.getObjectInstance(DataSourceFactory.java:244)
    at 
org.apache.naming.factory.FactoryBase.getObjectInstance(FactoryBase.java:94)
    at 
java.naming/javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:341)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:840)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173)
    at 
org.apache.catalina.core.NamingContextListener.addResource(NamingContextListener.java:1017)
    at 
org.apache.catalina.core.NamingContextListener.createNamingContext(NamingContextListener.java:557)
    at 
org.apache.catalina.core.NamingContextListener.lifecycleEvent(NamingContextListener.java:253)
    at 
org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:123)
    at 
org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5048)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at 
org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:713)
    at 
org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:690)
    at 
org.apache.catalina.core.StandardHost.addChild(StandardHost.java:705)
    at 
org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:978)
    at 
org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1849)
    at 
java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at 
org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at 
java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:123)
    at 
org.apache.catalina.startup.HostConfig.deployWARs(HostConfig.java:773)
    at 
org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:427)
    at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1576)
    at 
org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:309)
    at 
org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:123)
    at 
org.apache.catalina.util.LifecycleBase.setStateInternal(LifecycleBase.java:423)
    at 
org.apache.catalina.util.LifecycleBase.setState(LifecycleBase.java:366)
    at 
org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:929)
    at 
org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at 
org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1377)
    at 
org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1367)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at 
org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at 
java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:145)
    at 
org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:902)
    at 
org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at 
org.apache.catalina.core.StandardService.startInternal(StandardService.java:421)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at 
org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:932)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:633)
    at 
java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native 
Method)
    at 
java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
    at 
java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:567)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:344)
    at 
java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native 
Method)
    at 
java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
    at 
java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:567)
    at 
org.apache.commons.daemon.support.DaemonLoader.start(DaemonLoader.java:241)
Caused by: java.lang.ClassNotFoundException: Unable to load class: 
com.mysql.jdbc.Driver from 
ClassLoader:java.net.URLClassLoader@4617c264;ClassLoader:ParallelWebappClassLoader
...

Has anyone ever seen this?

Thanks,

Andrea