Pivotal opted to partner with Rackspace because Rackspace is capable to supporting instances of Cloud Foundry running on a public cloud, in a hosting center or on-premises, he says, adding that 60 percent of the Pivotal instances run on VMware vSphere platform, while the rest are distributed across multiple clouds and other on-premises environments. Pivotal is a sister company of VMware, operating under the umbrella of Dell Technologies.