If you do not want to invest in any physical hardware, you might be interested in a cloud-based option. In this case, you are renting virtual resources like any other customer on the public cloud, but inside the virtual machine, a virtualized ESXi server is running.

This approach might be ideal for short-term projects, where you pay only for resources that you have used over a period of time. For a long-term project, however, the price might not be that attractive when compared to physical servers.

The advantages of using cloud-based solutions are as follows:

• They can be deployed within minutes
• They can be cheap for short-term projects
• They are software defined, so there is no need for any additional infrastructure

The disadvantages of using cloud-based solutions are as follows:

• They can be expensive for long-term projects
• The solution is delivered as is, and you can't customize some of the components

Note that you can't run ESXi inside a virtual machine. The service provider must explicitly support this function (nested virtualization). If you try to install an ESXi hypervisor on an Amazon AWS EC2 instance, for example, it won't work correctly. Several companies specialize in nested environments. These include Ravello (https://cloud.oracle.com/en_US/ravello) and VMlabs (https://www.vmlabs.io).