Thanks this is helpful, but I was curious. If there are versions of postgres installed on the system, how does ambari-server choose which one to run with? I actually have another system where I'm seeing the opposite. In this case postgresql-10 is running and postgresql (9.2) is not active after a restart. I'm just trying better understand how it choose which postgres service to start? ... View more

Thanks for your response. Sorry for my the late response, but I wanted to pass this along in case someone runs into this issue. So I did some more testing and what I found is that I had an incompatible postgresql-jdbc driver. So I was upgrading from 9.6 to 10.x and it appears the jdbc driver I was using was pretty old and incompatible with version 10.x. Once I upgraded the postgresql-jdbc driver everything worked just fine. Here is what I did to resolve my issue:   wget https://jdbc.postgresql.org/download/postgresql-42.2.9.jar mv /usr/share/java/postgresql-jdbc.jar /usr/share/java/postgresql-jdbc.jar.old  (backing up the old driver) cp ~/postgresql-42.2.9.jar /usr/share/java/postgresql-jdbc.jar ambari-server setup --jdbc-db=postgres --jdbc-driver=/usr/share/java/postgresql-jdbc.jar     ... View more