CloudStack is described as 'Apache's CloudStack is a Project backed by Citrix and designed to be a direct competitor to OpenStack. It is designed to deploy and manage large networks of virtual machines, as a highly available, highly scalable Infrastructure as a Service (IaaS) cloud computing platform' and is a Cloud Computing service in the business & commerce category. There are more than 25 alternatives to CloudStack for a variety of platforms, including Web-based, Linux, Self-Hosted, SaaS and Windows apps. The best CloudStack alternative is OpenStack, which is both free and Open Source. Other great apps like CloudStack are OpenShift, Microsoft Azure, Laravel Cloud and Amazon Elastic Compute Cloud.
Its not a private cloud provider