Review: VMware vSphere 5.1 looms large

With the release of VMware vSphere 5.1, VMware's product line underwent some naming and positioning changes. In the past, there were two different bare-metal hypervisors, one free and one sold as part of the vSphere suite. Now there is just one. The new standard is ESXi 5.1, which still comes in a free version. However, the free version is now limited to 32GB of physical RAM.

The ESXi hypervisor is required for all vSphere installations starting with version 5.0. ESXi does not use Linux, as did ESX, for the service console that executed scripts and provided hooks for third-party agents. The new ESXi code base has shrunk, presenting a smaller attack surface and requiring less maintenance and patching. Higher reliability and stability in the hypervisor translate to fewer headaches for IT administrators and longer uptime for mission-critical applications.

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VMware has also introduced three different offerings under the label vCloud Suite, which include bundled products targeted at specific use cases. They are licensed on a per-CPU basis and come in Standard, Advanced, and Enterprise editions. These products provide the functionality to implement infrastructure-as-a-service (IaaS) clouds for large data centers or service providers. For this review I focused on the basic VMware vSphere functionality along with the VMware vCenter Server management system.

Installation and configuration
For the purpose of this review I used a Dell PowerEdge R715 server as the primary VMware ESXi host. Dell is a longtime VMware partner, and it has many convenient features, such as the ability to boot the base ESXi image from either an SD card or a USB disk. Dell provides this image on its website, and I used it to create a bootable USB device. Installing and configuring an ESXi host is pretty simple for most any supported hardware.

Configuring a vSphere environment is a different story. If you plan on using any of the more advanced features available from VMware, you will need to install vCenter Server. Here you have several options, such as using an existing Windows Server or deploying the vCenter Server as a virtual appliance (VA). The VA option uses Suse Linux as the base OS and a local database for small installations of less than 50 VMs. For larger installations you must use an external Oracle database. If you go the Windows Server route, you'll also need to have SQL Server installed to house the inventory database.

You must configure a separate network for all vMotion traffic before any virtual machine migrations can be accomplished. Each host participating in vMotion must have a minimum of two Ethernet adapters with at least one supporting Gigabit speeds. Each host must have a port group designated for vMotion traffic with source and destination hosts on the same subnet. That's quite a bit of configuration required to accomplish a migration -- especially when compared to Microsoft's Hyper-V live migration feature, which requires almost no configuration.