I am guess I was not sure exactly what needs to change in sonar.properties to connect to an external RDS Postgres and if I need to do anything (such as create the schema and user) in it but I did get it to work this time.
This is what I am doing after launching the ec2 instance using the bitnami sonarqube ami:
* sudo systemctl stop bitnami
* edit /opt/bitnami/apps/sonarqube/sonarqube/conf/sonar.properties
- comment out sonar.jdbc.url=jdbc:mysql...
- uncomment sonar.jdbc.url=jdbc:postgresql:... and change localhost to my rds endpoint
* change sonar.jdbc.username and password to what i used when creating the rds instance
* sudo systemctl start bitnami
This time it looks like it worked correctly (at least I see the connections in the rds console).
I think previously I changed the mysql jdbc property to be the postgres entry instead of commenting and uncommenting.
I notice that it still starts mysql on the ec2 host so I thought it trying to talk to it.
Is the mysql still used even though sonar is connecting to the RDS?