VMware vSphere® 5.5 is the latest release of the flagship virtualization platform from VMware. VMware vSphere, known in many circles as "ESXi", for the name of the underlying hypervisor architecture, is a bare-metal hypervisor that installs directly on top of your physical server and partitions it into multiple virtual machines. Each virtual machine shares the same physical resources as the other virtual machines and they can all run at the same time. Unlike other hypervisors, all management functionality of vSphere is possible through remote management tools. There is no underlying operating system, reducing the install footprint to less than 150MB.
Improved Reliability and Security
The ESXi bare-metal hypervisor architecture no longer relies on a service console for command-line management. By moving management functionality to the VMkernel, VMware® ESXi™ hypervisor has reduced its overall footprint from 2 GB to 150 MB. With a smaller attack surface for malware and over-the-network threats, your vSphere environment is considerably more secure and reliable.
Streamlined Deployment and Configuration
Since it has fewer configuration options and simpler deployment and configuration, the ESXi architecture makes it easy to maintain a consistent virtual infrastructure.
Reduced Management Overhead
VMware vSphere ESXi uses an agentless approach to hardware monitoring and system management with an API-based partner integration model. Management tasks are on remote command lines with the vSphere Command Line Interface (vCLI) and PowerCLI. PowerCLI uses Windows PowerShell cmdlets and scripts for automated management.
Simplified Hypervisor Patching and Updating
The smaller size and limited number of components mean that ESXi requires fewer patches than its VMware® ESX® predecessor. Fewer patches mean smaller maintenance windows and fewer scheduled maintenance windows. Over its lifetime, the ESXi requires approximately 10 times fewer patches than the ESX service console.
There's no longer a dependency on a shared root account when using the ESXi Shell. Local users who are assigned administrative privileges automatically have full shell access—there's no need to "su" to run commands as the root user.
Extensive Logging and Auditing
vSphere 5.5 logs all user activity from both the Shell and the Direct Console User Interface under the user's account. This logging ensures user accountability and makes it easy to audit user activity.
Live virtual machine migration allows you to combine vMotion and VMware vSphere® Storage vMotion® into a single operation. For small virtual infrastructure implementations, combined vMotion migration means that the entire virtual machine (memory, CPU and disk) moves from one host to another. In larger environments, enhanced vMotion means that you can live-migrate entire virtual machines from one cluster to another, even if those clusters don't share storage.
New Virtual Hardware
vSphere 5.5 introduces a new generation of virtual hardware with virtual machine hardware version 10, which includes the following features:
- Virtual machines can now support up to 64 virtual CPUs.
- Virtual machines can support up to 1 TB of RAM.
- New Advanced Host Controller Interface (AHCI) supports up to 120 devices per virtual machine.
- Maximum VMDK size increased to 62TB.
- Guest OS Storage Reclamation returns disk space to the storage pool when it's de-allocated from within the guest OS.
- Improved CPU virtualization by exposing more information about the host CPU architecture to virtual machines. This improved CPU exposure allows for better debugging, tuning and troubleshooting of operating systems and applications within the virtual machine.
Active Directory Integration
You can join vSphere hosts to your Active Directory domain. Once added, Active Directory handles user authentication and removes the need to create user accounts on each host.
Centralized Management of Host Image and Configuration via Auto Deploy
Combining the features of host profiles, Image Builder and PXE, VMware vSphere® Auto Deploy™ simplifies host installation and upgrade. The Auto Deploy library centrally stores all vSphere host images. Administrators can automatically provision new hosts based on user-defined rules and host rebuilds are as simple as a reboot.
vSphere ESXi now features a service-oriented and stateless firewall, which you can configure using the vSphere client or at the command line with ESXCLI. The new firewall engine eliminates the use of IPTABLES and allows administrators to define port rules for services. Additionally, you can specify IP ranges or individual IP addresses that can connect to host services.
For more information on the vSphere ESXi hypervisor, visit the ESXi Information Center.