Comment 2 for bug 1694391

To resolve the issue all I needed to do was:
$ sudo service postgresql start

I guess there is something in the sequencing of service start going wrong. I will try and look into it more later. I am not sure how Trac is packaged, how this server is setup and as a result how much of all this is a roll-your-own. I only raised this bug to keep track on things if this had all come out of a package upgrade in an odd way.