minMasterVersion

The minimum version of the master. GKE will auto-update the master to new versions, so this does not guarantee the current master version--use the read-only master_version field to obtain that. If unset, the cluster's version will be set by GKE to the version of the most recent official release (which is not necessarily the latest version). Most users will find the gcp.container.getEngineVersions data source useful - it indicates which versions are available. If you intend to specify versions manually, the docs describe the various acceptable formats for this field.

If you are using the gcp.container.getEngineVersions datasource with a regional cluster, ensure that you have provided a location to the datasource. A region can have a different set of supported versions than its corresponding zones, and not all zones in a region are guaranteed to support the same version.