Java HotSpot(TM) Server VM warning: You have loaded library /soft/sonar/sonarqube-6.7.6/bin/linux-x86-64/lib/libwrapper.so which might have disabled stack guard. The VM will try to fix the stack guard now.
It's highly recommended that you fix the library with 'execstack -c <libfile>', or link it with '-z noexecstack'.

WARNING - Unable to load the Wrapper's native library 'libwrapper.so'.
          The file is located on the path at the following location but
          could not be loaded:
            //soft/sonar/sonarqube-6.7.6/bin/linux-x86-64/./lib/libwrapper.so
          Please verify that the file is readable by the current user
          and that the file has not been corrupted in any way.
          One common cause of this problem is running a 32-bit version
          of the Wrapper with a 64-bit version of Java, or vica versa.
          This is a 32-bit JVM.
          Reported cause:
            //soft/sonar/sonarqube-6.7.6/bin/linux-x86-64/lib/libwrapper.so: //soft/sonar/sonarqube-6.7.6/bin/linux-x86-64/lib/libwrapper.so: wrong ELF class: ELFCLASS64 (Possible cause: architecture word width mismatch)
          System signals will not be handled correctly.

2019.05.14 15:20:12 INFO  web[][o.sonar.db.Database] Create JDBC data source for jdbc:mysql://localhost:3306/sonar?           useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useConfigs=maxPerformance&useSSL=false
2019.05.14 15:20:12 ERROR web[][o.s.s.p.Platform] Web server startup failed
java.lang.IllegalStateException: Can not connect to database. Please check connectivity and settings (see the prope           rties prefixed by 'sonar.jdbc.').
        at org.sonar.db.DefaultDatabase.checkConnection(DefaultDatabase.java:108)
        at org.sonar.db.DefaultDatabase.start(DefaultDatabase.java:75)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.picocontainer.lifecycle.ReflectionLifecycleStrategy.invokeMethod(ReflectionLifecycleStrategy.java:11           0)
        at org.picocontainer.lifecycle.ReflectionLifecycleStrategy.start(ReflectionLifecycleStrategy.java:89)
        at org.picocontainer.injectors.AbstractInjectionFactory$LifecycleAdapter.start(AbstractInjectionFactory.jav           a:84)
        at org.picocontainer.behaviors.AbstractBehavior.start(AbstractBehavior.java:169)
        at org.picocontainer.behaviors.Stored$RealComponentLifecycle.start(Stored.java:132)
        at org.picocontainer.behaviors.Stored.start(Stored.java:110)
        at org.picocontainer.DefaultPicoContainer.potentiallyStartAdapter(DefaultPicoContainer.java:1016)
        at org.picocontainer.DefaultPicoContainer.startAdapters(DefaultPicoContainer.java:1009)
        at org.picocontainer.DefaultPicoContainer.start(DefaultPicoContainer.java:767)
        at org.sonar.core.platform.ComponentContainer.startComponents(ComponentContainer.java:134)
        at org.sonar.server.platform.platformlevel.PlatformLevel.start(PlatformLevel.java:90)
        at org.sonar.server.platform.Platform.start(Platform.java:211)
        at org.sonar.server.platform.Platform.startLevel1Container(Platform.java:170)
        at org.sonar.server.platform.Platform.init(Platform.java:86)
        at org.sonar.server.platform.web.PlatformServletContextListener.contextInitialized(PlatformServletContextLi           stener.java:45)
        at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4745)
        at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5207)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1419)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1409)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Unknown system vari           able 'query_cache_size')
        at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549)
        at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388)
        at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
        at org.sonar.db.profiling.NullConnectionInterceptor.getConnection(NullConnectionInterceptor.java:31)
        at org.sonar.db.profiling.ProfiledDataSource.getConnection(ProfiledDataSource.java:323)
        at org.sonar.db.DefaultDatabase.checkConnection(DefaultDatabase.java:106)
        ... 29 common frames omitted
Caused by: java.sql.SQLException: Unknown system variable 'query_cache_size'
        at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3973)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3909)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2527)
        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2680)
        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2486)
        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2444)
        at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1381)
        at com.mysql.jdbc.ConnectionImpl.loadServerVariables(ConnectionImpl.java:3766)
        at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3229)
        at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2238)
        at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2024)
        at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:779)
        at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
        at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
        at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389)
        at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
        at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
        at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582)
        at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556)
        at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545)
        ... 34 common frames omitted
2019.05.14 15:21:07 WARN  web[][o.a.c.u.SessionIdGeneratorBase] Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [55,334] milliseconds.

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