Chef attributes are global variables that are available for every cookbook on the node. There are multiple formats to declare and use an attribute. For important notes on the syntax, please see Undefined method or attribute error in a Chef recipe.
To override the value of an attribute that is defined in another cookbook, use the following syntax
node.override['ATTRIBUTE_NAME'] = 'NEW_VALUE'
During compilation, this line will replace the default value of the attribute with the NEW_VALUE.