My Vagrant configuration for Ubuntu 12.04 LTS 64-bit and PostgreSQL 9.3 database.
You need to install omnibus plugin to ensure that the latest Chef is installed (minimum required version is 11.0):
vagrant plugin install vagrant-omnibus
Then execute the usual:
vagrant up
And you're good to go. Now you have PostgreSQL running on a virtual machine with the default port 5432 mapped outside and ready to accept connections.
Username is vagrant, password is password, initial db is vagrant, but you can change these in Vargant file.
For example you can connect to PostgreSQL with psql:
psql -h localhost -p 5432 -U vagrant vagrant