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Feature Description

Currently for the EBS builder, when using spot instances the user has the option of specifying the maximum spot price threshold. This is achieved through the spot_price parameter. However, the default value for this parameter is 0, which is the equivalent of using on-demand price. Due to the user wanting to user spot instances to reduce cost, it makes sense to have the default value be auto.

Use Case(s)

Any user wanting to user spot instances and is comfortable letting Packer use its logic to determine the best spot price.