The current access logs in the logs directory, does not contain the username. The sonar.properties configuration file do not seem to provide a way to customize the log format in a way to log the username. Is there any way to match the logged username in each access.log entry?
I take for good Simon's answer in the comment:
"I confirm that it's not possible to log username in access.log. It will be fixed in versions 6.x : jira.sonarsource.com/browse/SONAR-7581" -- Simon Brandhof - SonarSource