Lots of companies these days are stretching their hardware and energy dollars by consolidating print, file, DNS, and Web servers on virtualization platforms such as VMware. But not many companies boast of running their entire production infrastructure on virtual machines. An exception is Arvato Mobile, a division of Bertelsmann that builds mobile solutions for network operators, media companies, and Internet portals and delivers digital entertainment content to consumers around the globe.

Based in Hamburg, Germany, Arvato Mobile handles mobile game management for O2 Germany, fixed-line ring-back tones for Vodafone, and general mobile content delivery for a number of telcos, including Connex, Orange, and T-Mobile. The company also provides DRM-protected music to Mobilcom and delivers high-definition movies for JPC, Terra Lycos, and Warner through its own peer-to-peer distribution network on the same day the DVDs become available in stores.

"For music labels such as EMI, we do the central content aggregation, partner distribution, and transcoding of their soon-to-be-released albums," says Lukas Losche, the company's director of IT operations. "All of these applications need to have 100 percent uptime, and they are very demanding in terms of system resources, system scalability, and especially system security. Imagine an unreleased music album being stolen from our systems prior to its release -- this must never happen."

Despite these heavy demands, all of these applications run on a virtualized infrastructure. The server virtualization platform is SWsoft's Virtuozzo. As opposed to hypervisors such as VMware ESX and Xen, Virtuozzo virtualizes the operating system, meaning that all of the guest operating systems must share the same kernel. The downside is that Linux and Windows VMs -- which SWsoft dubs VPSes (Virtual Private Servers) -- cannot share the same physical hardware. The upside is very low overhead, allowing many virtual servers to share the same hardware without affecting performance.

Arvato Mobile is running about 600 virtual servers, both Linux and Windows, comprising nearly the entire infrastructure for development and testing, internal apps, and critical applications, including content processing, licensing, distribution, royalty management, and user support. Even the company's Microsoft SQL Server and MySQL database clusters and Business Objects reporting servers run on Virtuozzo. Behind the servers, several hundred terabytes of disc and tape storage are virtualized, using grid storage components, into a single file system namespace.

Every VPS has a specific purpose, says Losche, either a particular application or specialized service. Five to 10 virtual servers are loaded on each physical server, with the exception of databases, each of which is loaded on a single box. All take advantage of the real-time resource management, integrated backup, live migration, and disaster recovery that Virtuozzo provides.

"If we detect a hardware error, we are able to move a database server from one hardware node to another with practically zero downtime," Losche reports.

Migrating applications from physical to virtual systems has become easier since SWsoft provided a P2V (physical to virtual) wizard late last year.

"Until now, we've always had physical servers inside different VLANs and security zones," Losche says. "In the future, we'll loosen this concept so that only the VPSes reside in different VLANs, but the hardware nodes have fixed trunks inside the same VLAN. That way we won't need spare resources for each security zone but instead can have a pool of spare resources for all zones and assign them dynamically."