Message: NameError: undefined local variable or method `override' for main:Object

[hawksbill]

$ vagrant up --provider=aws
There was an error loading a Vagrantfile. The file being loaded
and the error message are shown below. This is usually caused by
a syntax error.

Path: <provider config: aws>
Line number: 6
Message: NameError: undefined local variable or method `override' for main:Object

The issue here was this line in the Vagrantfile

config.vm.provider "aws" do |aws|

The override configuration options were not being recognised because the override options were not added to the do list, like this.

config.vm.provider "aws" do |aws, override|