We use a base tier MongoDB cluster (M20) and an analytics tier (M30), where they are of different sizes due to different business requirements.
Currently this is not supported by Terraform unless tiers use the same hardware (e.g. either both are set to M20 or M30).
See the error message below.
Error: error reading MongoDB Cluster (development): GET https://cloud.mongodb.com/api/atlas/v1.0/groups/1234567890/clusters/development: 400 (request "ASYMMETRIC_HARDWARE_INVALID") Asymmetric hardware is not supported by the v1.0 API. Please use the v1.5 API instead. Documentation for the v1.5 API is available at https://docs.atlas.mongodb.com/reference/api/clusters-advanced/.
Please add v1.5 API support to Terraform to support asymmetric hardware.