title: How to update soanr.properties of docker based installation
body: <p>I am pretty new to Docker. Now I want to run a docker version of Sonarqube and upate the property file (sonar.properties) inorder to point my databsae to mysql rather than the default H2. </p>
  
  <p>I am able to run the image with default configuration and even performed a scan on it. While following the instructions in its official docker page (<a href="https://hub.docker.com/_/sonarqube/?tab=description" rel="nofollow noreferrer">Sonarqube docker documentation</a>), I am not able to proceed further from the second point under the "First Installation" heading. Second point is as follows</p>
  
  <pre><code>Initialize SONARQUBE_HOME folder tree with --init. This will initialize the default configuration, copy embedded plugins, and prepare the data folder:
  
  $ docker run --rm \
  -v $SONARQUBE_HOME/conf:/opt/sonarqube/conf \
  -v $SONARQUBE_HOME/extensions:/opt/sonarqube/extensions \
  -v $SONARQUBE_HOME/data:/opt/sonarqube/data \
  sonarqube --init
  </code></pre>
  
  <p>which I believe will help me to have a custom configurations folder. Following error shows up while running this command.</p>
  
  <blockquote>
    <p>renju@renju-pc:~$ sudo docker run --rm -v
    $SONARQUBE_HOME/conf:/opt/sonarqube/conf -v
    $SONARQUBE_HOME/extensions:/opt/sonarqube/extensions -v
    $SONARQUBE_HOME/data:/opt/sonarqube/data sonarqube --init tail: cannot
    open './logs/es.log' for reading: No such file or directory
    01:33:11.950 [main] WARN
    org.sonar.application.config.AppSettingsLoaderImpl - Configuration
    file not found: /opt/sonarqube/conf/sonar.properties Exception in
    thread "main" java.lang.IllegalArgumentException: Command-line
    argument must start with -D, for example -Dsonar.jdbc.username=sonar.
    Got: --init   at
    org.sonar.application.config.CommandLineParser.argumentsToProperties(CommandLineParser.java:56)
      at
    org.sonar.application.config.CommandLineParser.parseArguments(CommandLineParser.java:37)
      at
    org.sonar.application.config.AppSettingsLoaderImpl.load(AppSettingsLoaderImpl.java:66)
      at org.sonar.application.App.start(App.java:51)     at
    org.sonar.application.App.main(App.java:98)</p>
  </blockquote>
  
  <p>My asumption is that it is because of the unavailability of the folder "opt/sonarqube/conf". </p>
  
  <p>Why is that folder missing? As per doc,</p>
  
  <pre><code>Use bind-mounted folders
  The images contain the SonarQube installation at /opt/sonarqube. You need to use bind-mounted folders to override selected files or directories :
  
  /opt/sonarqube/conf: configuration files, such as sonar.properties
  /opt/sonarqube/data: data files, such as the embedded H2 database and Elasticsearch indexes
  /opt/sonarqube/logs: contains SonarQube logs about access, web process, CE process, Elasticsearch logs
  /opt/sonarqube/extensions: plugins, such as language analyzers
  </code></pre>
  
  <p>Am I missing any intermediate steps here?</p>
  
  <p>I work on Ubuntu 19.10.</p>