When VMware launched ESX Server 3.5 in September 2007 it also introduced a parallel architecture for its hypervisor: 3i.
The main difference between traditional ESX Server and the 3i version is the lack of the Console Operating System (COS), the customized Red Hat Enterprise Linux distribution that VMware uses to manage and give access to a series of features in the hypervisor.
ESX Server 3i doesn’t really drop the RHEL-based COS but replaces it with a much smaller distro called BusyBox, tailored to provide a minimal set of services.
The modifications that VMware introduced into ESX Server 3i along with the adoption of BusyBox allowed to produce a small-footprint hypervisor with doesn’t need installation: just like ubiquitous LiveCD distribution slike Knoppix, it boots from a CD, a USB key or a new Solid-State Drive (SSD) and is ready to go.
At launch time VMware executives reported in different occasions that over time the 3i architecture would replace the traditional one, so that newer versions of ESX Server wouldn’t come in two different editions.
VMware didn’t provide any roadmap for the take-over but a new interview with Raghu Raghuram, Vice President of Products and Solutions at VMware, published by RedmondMag seems to imply that it’s about to happen sooner than later.
Raghuram says that the 3i architecture will become mainstream over the course of this year, which may just mean that VMware expects a major adoption of ESX Server 3i during the 2008. But it also may mean that the company is preparing to release an ESX Server update with 3i architecture only.
The second speculation seems more likely considering that ESX Server 3i is on the market since just three months, and it would hardly replace most of the existing installations in the upcoming nine months.