eWeek Labs tests have shown that server blade systems will provide performance scalability, plug-and-play serviceability and management advantages over industry-standard server systems. However, blades are not the only path to these benefits. IT departments considering blade systems should not make a final decision until theyve also evaluated the return on server virtualization investment.
Server virtualization software can be used to deploy multiple virtual partitions within an industry-standard server. The partitions, called virtual machines, can run operating systems independent of one another. The operating systems that run in the virtual machines are called guest operating systems, and each guest system can run different applications without conflicts within the same physical server.
Companies can use server virtualization software to consolidate resources and solve application or operating system compatibility problems. Server virtualization is also a good choice for sites that have idle server hardware or have already made significant investments in server hardware and are reluctant to make the leap to newer technology.
Last month, virtualization pioneer VMware Inc. released the latest version of its enterprise server virtualization software, ESX Server 1.5, which provides advanced virtualization capabilities to enterprise environments.
Once installed, ESX Server takes over the server and creates a virtual architecture for partitioning—a VMware virtualization layer over the physical hardware in the server. The virtual machines, resource manager and service console run independently on top of the virtualization layer. Standard hardware such as processors, memory, network cards, I/O devices and video are isolated and virtualized as resources for allocation to virtual machines.
The ESX guest operating systems access the virtual hardware as if the devices were natively installed. The virtual machines are encapsulated in several files for easy duplication and can be easily migrated to another virtual machine within the same server or to another server. This makes the deployment of virtual machines to environments such as server farms easy and flexible.
The latest version of ESX Server allows for the deployment of as many as 64 virtual machines per server and boosts the maximum memory supported to 64GB (with a 3.6GB limit per virtual machine). ESX supports Windows NT and 2000 Server/ Advanced Server, Linux, and FreeBSD.
The total cost of ESX Server depends on the hardware and the number of virtual machines running because each will require an operating system license. Running ESX on high-end four-way or eight-way servers can easily cost more than $30,000—about the price of a filled blade chassis from Hewlett-Packard Co. or RLX Technologies Inc. Bear in mind, though, that ESX can be installed on existing hardware, and a high-end eight-way server can support as many as 64 virtual machines.
ESX Server and the virtual machines in a physical server can be managed via the ESX Web interface or using a remote keyboard, video and mouse console on another PC. The ESX Server also supports SNMP for integration with network management tools such as HP OpenView.
Virtutech ABs Simics, SWsoft Inc.s Virtuozzo, Ensim Corp.s ServerXchange and the User-Mode Linux project also offer software-based virtualization, while Unisys Corp.s ES7000 Intel Corp.-based servers have partitioning in hardware.
Technical Analyst Francis Chu can be reached at email@example.com. Links to additional articles in this Special Report:
- Blade to Order
- Two Blades Cut Path to Manageability
- F5, Jareva Management Tools Rein in Blade Systems