There may be occassions where it’s useful to specify the subnet used in your Bake stage. Targeting a specific subnet can ensure your Packer Builders (which Spinnaker relies on for baking images) are assigned a subnet which meets the requirements of the network (e.g. a subnet which does not auto-assign a public IP).
Specifying a subnet is handled through the Extended Attributes of the Bake stage’s Bake Configuration. You will need to know the id of your subnet and associate it with the aws_subnet_id key.