Parallels, Inc.#Server software
Virtuozzo (pronounced " Virtuoso" ) is a proprietary software to virtualize operating systems, and is used by Parallels, Inc. ( prior to 2008 SWsoft, Inc.) developed and distributed. The Linux version is available since 2001, the Microsoft Windows version has been available since 2005. The Linux version of Virtuozzo based on OpenVZ.
Description
Virtuozzo creates multiple isolated virtual instances of operating systems on a single physical server. Thus there is the possibility to use existing hardware for multiple (virtual) servers to reduce the management of systems and even to save on licensing costs, depending on the installation. The virtual servers behave mostly as if they were a single physical server. All instances have their own computer management (administration of groups and users, services, disk management), its own IP address (es), processes, data, applications, system libraries and administrative files. Each virtual instance has its own network range and is therefore accessible via network. Each instance can have its own routing tables and firewall rules, however, do not load your own kernel modules (eg for advanced firewall functionality ) due to the shared kernel.
Operating system virtualization
Virtuozzo virtualizes not hardware-based - as other software often does - but on the base operating system. All instances running on a single kernel (similar to the KVM). The virtualization mechanism Virtuozzo " multiplied " this kernel, so that the instances seem to run as its own operating system, especially from the point of view of applications, users, and network services. Thus, the software generates less load on the system than other virtualization software. On a physical server as more virtual instances can run at the same time as usual. Virtuozzo supports up to 64 x 86 processors and 64 GB of RAM, but usually are 1 - to be found far more often in practice to 4 - processor machines.
Compared with other techniques
Virtuozzo is fundamentally different from other, more common techniques. The objectives of the developers were to produce much server load and as simple as possible to make the management. The technique based on a particular operating system, is less suitable since they usually require testing environments with many different operating systems for developers. For several years, Virtuozzo is successfully used at different hosters with hundreds of different users.