VMware's Project Photon is a technology preview of a lightweight Linux operating system designed to be used as a container host.
Project Photon supports several common container formats including Docker, CoreOS's Rocket and Pivotal's Garden. The operating system is optimized to run as a guest operating system on VMware's vSphere hypervisor, giving developers and system administrators a lightweight host on which to deploy application containers.
In this example, vSphere would be installed on a physical server as a bare-metal hypervisor. An administrator would use vSphere to create a virtual machine and install Project Photon as the guest operating system. Then, and administrator could deploy one or more application containers – which all share a common Linux kernel – on top of that guest. The portability advantages containers offer allow administrators to more easily move a developer's application from a test or development environment into production. Hosting containers within a virtual machine means that administrators can use existing VM-management tools (such as vSphere) to manage those workloads.
Project Photon's small footprint allows a virtual machine to boot faster than a one running a conventional operating system, such as Windows Server. In addition to faster boot times, a lightweight operating system can save significant disk space. Project Photon has an installation footprint of about 300 MB, compared to 6.3 GB for a full installation of Windows Server 2012.
The open source project is not commercially supported by VMware.
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