OpenVZ Virtualization Keeps E-mail Filtering Service Up and Running

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Jenny Ellis
+44 (0) 20 7436 0420

OpenVZ Virtualization Keeps E-mail Filtering Service Up and Running Uses Operating System Virtualization to Manage its Network of Servers

HERNDON, Va., November 15, 2007 -- works in the dangerous area of sorting through e-mail to filter out viruses and junk e-mails known as "spam," so that its clients receive only the e-mails they want to see. For higher levels of control and security, it uses open source virtualization software, known as OpenVZ.

"In our business, it's a necessity to have redundant systems in different locations in case bad things happen," says Marc Perkel, support manager at "People are dependent on us to get their e-mail through, so we cannot afford downtime."

The company has set up virtual servers with OpenVZ operating system server virtualization software and maintains backups so that, if necessary, a virtual server can be restored on another physical server and started up immediately.

There are four OpenVZ virtual servers on each of four physical servers that run e-mail server software, MySQL and SpamAssassin with virtual servers as large as 4 gigabytes.

"OpenVZ has almost no overhead, so we are giving up almost nothing in terms of performance to run virtual servers," says Perkel. "In our experience, OpenVZ has been compatible with most everything we run so it's one of those 'just works' solutions."

"We run different software programs in different virtual servers," says Perkel. "That way, one application isn't compromised if another application has an issue."

"With OpenVZ, we can also limit applications to specified amounts of memory and processing power, which allows us to tune our resources very precisely. If necessary, those can be adjusted on the fly," says Perkel.

The company has used OpenVZ software to create templates for different virtual servers, such as its VoIP phone system and SpamAssassin servers that process e-mail. Each virtual server is deployed on a physical server independent of others, which enables virtual servers to be moved among physical servers to balance workloads.


E-mail filtering is easy to set up and doesn't require users to change their existing e-mail server. Instead of e-mail coming from the Internet directly to the user's e-mail server, it goes to spam filtering e-mail servers. There, it is stripped of viruses and spam and within seconds is passed on to the user's existing e-mail server. is based in San Bruno, California. More information can be found at

About the OpenVZ Project

The OpenVZ project freely distributes and offers support to its users, promoting operating system virtualization through a collaborative, community effort. Supported by SWsoft, the OpenVZ project serves the needs of the community developers, testers, documentation experts, and other technology enthusiasts who wish to participate in and accelerate the technology development process. OpenVZ is open source software that is used as the basis for the SWsoft Virtuozzo virtualization software product.

Since going into full production late in 2005, the OpenVZ project has been very active with the user community with more than 20,000 message posts on its support Forum. The OpenVZ website attracts tens of thousands of visitors each month as more businesses and individuals explore and contribute to the leading open source operating system virtualization project.

About OpenVZ

OpenVZ is operating system server virtualization software technology, built on Linux, which creates multiple isolated, secure virtual environments on a single physical server – enabling greater server utilization and superior availability with fewer performance penalties. The virtual servers ensure that applications do not conflict and can be re-booted independently.

With the power of today's processors, hardware is often under utilized. With virtualization technology, the server can effectively be split into many small ones, each running its tasks so that the whole server is utilized more efficiently.

OpenVZ software can be used to help consolidate servers and increase server utilization rates, or for creating "sandboxes" for test and development, or when sharing resources so that every user can have root access while being kept isolated from each other.

The OpenVZ software comes with user tools that help automate management of virtual servers. With its unique architecture that uses a single operating system instance, the virtual servers perform and execute like independent servers with their own memory, configuration files, users and applications. Each can be re-booted independently. Using template-based application deployment provides a simple way to get new virtual servers up and running in minutes and OpenVZ can run several times more virtual servers per CPU than other virtualization technologies. Also, the OpenVZ project maintains a blog site discussing virtualization technology, which can be accessed here,