Vagrant/VirtualBox VM provisioning: rbenv installs successfully but subsequent uses in script fail

I had a similar problem because I was trying to install rbenv and the vagrant provisioning was giving me the error:

==> default: /tmp/vagrant-shell: line 10: rbenv: command not found

First of all, it is very important to understand that vagrant provisioning script is running in sudo mode. So, when in the script we refer to ~/ path, we are referring to /root/ path and not to /home/vagrant/ path. The problem is that I was installing rbenv for the root user and after trying to call rbenv command from a vagrant user and, of course, it didn't work!

So, what I did is specify the vagrant to run the provisioner NOT in sudo user, adding privileged: false:

config.vm.provision :shell, privileged: false, inline: $script

Then in my script I considered everything as being called from the vagrant user. Here @Casper answer helped me a lot, because it works only specifying: sudo -H -u vagrant bash -i -c '......'

Since you just updated .bashrc with a new path and other settings, you will want to run "sudo bash" with the -i option. This will force bash to simulate an interactive login shell, and therefore read .bashrc and load the correct path for rbenv.

Below is my final Vagrantfile.

# -*- mode: ruby -*-
# vi: set ft=ruby :

$script = <<SCRIPT
  sudo apt-get -y update
  sudo apt-get -y install curl git-core python-software-properties ruby-dev libpq-dev build-essential nginx libsqlite3-0 libsqlite3-dev libxml2 libxml2-dev libxslt1-dev nodejs postgresql postgresql-contrib imagemagick

  git clone https://github.com/sstephenson/rbenv.git ~/.rbenv
  echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
  echo 'eval "$(rbenv init -)"'               >> ~/.bashrc
  source ~/.bashrc

  git clone https://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
  sudo -H -u vagrant bash -i -c 'rbenv install 2.1.3'
  sudo -H -u vagrant bash -i -c 'rbenv rehash'
  sudo -H -u vagrant bash -i -c 'rbenv global 2.1.3'
  sudo -H -u vagrant bash -i -c 'gem install bundler --no-ri --no-rdoc'
  sudo -H -u vagrant bash -i -c 'rbenv rehash'
  sudo -u postgres createdb --locale en_US.utf8 --encoding UTF8 --template template0 development
  echo "ALTER USER postgres WITH PASSWORD \'develop\';" | sudo -u postgres psql
SCRIPT

VAGRANTFILE_API_VERSION = "2"

Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
  config.vm.box = "hashicorp/precise64"
  config.vm.network "forwarded_port", guest: 3000, host: 3000

  # config.vm.provider :virtualbox do |vb|
  #   vb.customize ["modifyvm", :id, "--memory", "1024"]
  # end

  config.vm.provision :shell, privileged: false, inline: $script
end

Hope it will be helpful to someone else.

I'm surprised the provisioning script exits, as running su vagrant should in theory hang the script at that point (you're running the command su which does not normally exit by itself).

The problem is you cannot change the user that is running a shell script "on the fly" by running su.
Your only option is to use sudo.

Since you just updated .bashrc with a new path and other settings, you will want to run "sudo bash" with the -i option. This will force bash to simulate an interactive login shell, and therefore read .bashrc and load the correct path for rbenv.

So, something like this should hopefully work:

echo "building ruby"
sudo -H -u vagrant bash -i -c 'rbenv install 2.2.1 ...'