It’s difficult. But both VMware vSphere and Openstack offers the private cloud solutions.Openstack is made to enhance the existing technology and provide the on-demand basis virtual resources. This ecosystem software can help to reduce the power , Cost. Openstack has almost 30+ approved services within it where as VMware vSphere is offering less than 5 (compute, storage, image , networking, & Dashboard).
Unlike VMware , you no need to check for the hardware compatibility for Openstack. The Openstack controller node can even run on “whitebox” commodity hardware. Openstack has the block IO based storage(swift) for the instances but VMware doesn’t have it. Openstack is just 4 years old and only 10 release had in the past. So it requires some time to reach the enterprise computing.
But where as VMware reached high in the enterprise virtualization market. Since the Openstack’s icehouse release, most of the companies are joined with Openstack and aggressively they are making the progress to reach the customers. When it comes to cloud , people will be always questing about the security. I think openstack has considerably cleared that boundary with strong POC (Proof of concept). Note that VMware also supports the openstack development and they have integrated openstack with vCenter servers.
In VMworld 2015 , VMware has proudly announced VIO 2.0 (VMware Integrated OpenStack 2) with many new features including seamless upgrade, LBaaS ,Ceilometer , Qcow2 image support etc. Openstack supports almost all the hyper-visors in the world including VMware ESxi , Xen , KVM and Hyper-V. Its default hyper-visor is KVM. Where as VMware only supports their own hypervisor ESXi. This motivates to use Openstack than VMware. Another thing is that , VMware VIO (VMware Integrated Openstack) is an appliance which is deployed on top of VMware vCenter. vCenter also performs the similar tasks like Openstack.
Not sure how we can scale of the environment using the VIO2 . Some of the reports admitted that VMware Integrated Openstack customers are more than the Redhat Openstack customers. But those are existing VMware customers and they have shown the interest on VMware Integrated Openstack. Looks like customers would like evaluate the openstack on their existing environment without any additional cost since they may invested some millions of dollars on that. Openstack is free software but you have to pay bit more for the support. It also requires lot of skills and very difficult to get people from the market.
According to me , Openstack + KVM hypervisor would really save lot of money but you should get the right people to design it properly. At the same time , it can be integrated with VMware hypervisor & Hyper-V to utilize the existing infrastructure. VMware is already invested on the vCloud director (vCloud Automation centre) for the private cloud solutions. They have also invested in Openstack for the similar solutions. This increases the companies investment on the different technology for same solutions. EMC is the parent company of VMware. Recently they have acquired virtustream who is the hybrid cloud solutions provider.
In this case, Both Parent and child companies are investing on the different cloud technologies for the same solutions which makes more confusing. Looks like EMC is planning to buy the remaining stake of VMware to tighten the grip on VMware to save $ 1 Billion annually by avoiding the double investments for same solutions. It’s a right time for companies to start use of Openstack. At the same time , it better to use multiple hyper-visors like KVM , Xen , VMware ESXi to make the flexible environment in the private cloud.