imageId

The ID of the Amazon Machine Image (AMI) to use for instances launched with this override. When using Instance Refresh with ReplaceRootVolume strategy, this specifies the AMI for root volume replacement operations.

For ReplaceRootVolume operations:

• All overrides in the MixedInstancesPolicy must specify an ImageId

• The AMI must contain only a single root volume

• Root volume replacement doesn't support multi-volume AMIs