Permission problems Phusion Passenger Standalone must be able to write to the following directory: <%= @dir %> But it can't do that, despite the fact that it's running as root. There's probably a permission problem, or (if you're running on a RedHat/CentOS-based Linux distribution) SELinux might be interfering. Please fix the permissions for the aforementioned directory and/or disable SELinux, and re-run Phusion Passenger Standalone.