SonarQube not starting on Ubuntu 16.04 - sonarqube

Question

I have followed these steps http://www.voyalab.com/2016/10/06/install-sonarqube-ubuntu/and install sonarqube on ubuntu 16.04
But i am not able to start it on my machine.
log file :-
2017.02.15 07:33:40 ERROR web[o.a.c.c.StandardContext] One or more listeners failed to start. Full details will be found in the appropriate container log file
2017.02.15 07:33:40 ERROR web[o.a.c.c.StandardContext] Context [/sonar] startup failed due to previous errors
2017.02.15 07:33:40 WARN web[o.a.c.l.WebappClassLoaderBase] The web application [ sonar] appears to have started a thread named [Timer-0] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
java.lang.Object.wait(Native Method)
java.util.TimerThread.mainLoop(Timer.java:552)
java.util.TimerThread.run(Timer.java:505)
2017.02.15 07:33:40 INFO web[o.a.c.h.Http11NioProtocol] Starting ProtocolHandler ["http-nio-127.0.0.1-6000"]
2017.02.15 07:33:40 INFO web[o.s.s.a.TomcatAccessLog] Web server is started
2017.02.15 07:33:40 INFO web[o.s.s.a.EmbeddedTomcat] HTTP connector enabled on port 6000
2017.02.15 07:33:40 WARN web[o.s.p.ProcessEntryPoint] Fail to start web
java.lang.IllegalStateException: Webapp did not start
at org.sonar.server.app.EmbeddedTomcat.isUp(EmbeddedTomcat.java:84) ~[sonar-server- 6.0.jar:na]
at org.sonar.server.app.WebServer.isUp(WebServer.java:47) [sonar-server-6.0.jar:na]
at org.sonar.process.ProcessEntryPoint.launch(ProcessEntryPoint.java:105) ~[sonar-process- 6.0.jar:na]
at org.sonar.server.app.WebServer.main(WebServer.java:68) [sonar-server-6.0.jar:na]
2017.02.15 07:33:40 INFO web[o.a.c.h.Http11NioProtocol] Pausing ProtocolHandler ["http-nio-127.0.0.1-6000"]
2017.02.15 07:33:41 INFO web[o.a.c.h.Http11NioProtocol] Stopping ProtocolHandler ["http-nio-127.0.0.1-6000"]
2017.02.15 07:33:42 INFO web[o.a.c.h.Http11NioProtocol] Destroying ProtocolHandler ["http-nio-127.0.0.1-6000"]
2017.02.15 07:33:42 INFO web[o.s.s.a.TomcatAccessLog] Web server is stopped
2017.02.15 07:33:42 INFO app[o.s.p.m.Monitor] Process[es] is stopping
2017.02.15 07:33:42 INFO es[o.s.p.StopWatcher] Stopping process
2017.02.15 07:33:42 INFO es[o.elasticsearch.node] [sonar-1487124198721] stopping ...
2017.02.15 07:33:42 INFO es[o.elasticsearch.node] [sonar-1487124198721] stopped
2017.02.15 07:33:42 INFO es[o.elasticsearch.node] [sonar-1487124198721] closing ...
2017.02.15 07:33:42 INFO es[o.elasticsearch.node] [sonar-1487124198721] closed
2017.02.15 07:33:43 INFO app[o.s.p.m.Monitor] Process[es] is stopped
<-- Wrapper Stopped
I guess this is our main problem :-
Caused by: com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host localhost, port 1433 has failed. Error: "Connection refused (Connection refused). Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.".
at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:191) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SQLServerException.ConvertConnectExceptionToSQLServerException(SQLServerException.java:242) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SocketFinder.findSocket(IOBuffer.java:2280) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.TDSChannel.open(IOBuffer.java:493) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1387) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:1068) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectInternal(SQLServerConnection.java:904) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:451) ~[sqljdbc42.jar:na]
at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1014) ~[sqljdbc42.jar:na]
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) ~[commons-dbcp-1.4.jar:1.4]
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582) ~[commons-dbcp-1.4.jar:1.4]
at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556) ~[commons-dbcp-1.4.jar:1.4]
at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545) ~[commons-dbcp-1.4.jar:1.4]
... 35 common frames omitted

Answer 1

Logs are reporting :
Connection refused (Connection refused). Verify the connection
properties. Make sure that an instance of SQL Server is running on the
host and accepting TCP/IP connections at the port. Make sure that TCP
connections to the port are not blocked by a firewall.
Please verify your database configuration