OpenVZ is also known as Open virtualization is an operating system level platform that is based on Linux kernel and can run system that is based on Linux architecture. It can run multiple Linux system instances in what is called as containers. It contains Linux base operating system and gives very high performance compared to standalone servers. OpenVZ is free to use and imply. It provides custom level kernel to provide the support for its containers and user level tools.
The container consists of:
OpenVZ is a operating system level virtualization platform and provides features like:
OpenVZ utilizes the processing power to reduce the overhead by decreasing the load that is given on a system. It provides better methods to improve the handling of peak loads. It also reduces the complexity by providing standardized and centralized management of the server from one place. It provides a way to isolate the servers from the actual hardware. It uses high-end servers by isolating the server from hardware and with the servers bring added advantages like reliability, longer lifespan, etc.
OpenVZ uses tun/tap network module to configure a container. To setup the container using tun/tap device:
The commands that are required to manage OpenVZ are as follows:
To show a list of all running VPSs we require a command named vzlist that list the containers and its parameters.The command that is used with it is:
The commands can have many parameters like -o that displays only specified parameters with the name.
To calculate the usage for each container's resources a command named vzcalc is used that show all the shared host system resources that is used by a particular container.-v is the parameter that is used to show only the valid containers that are currently in use.
To over-commit the memory in OpenVZ few pages has to be modified like vmguarpages and oomguarpages that provides the resource management configuration files. Out of these vmguarpages provides the maxium memory a container can have and oomguarpages provides the maximum memory that is being consumed by the processes. These are used to set the limit. Limit also has some files like privvmpages that puts an upper limit on container memory. It is also used for non-swappable kernel memory. By using these functions over-commitment of the memory can be done by using OpenVZ.
Veth stands for virtual ethernet device and it is used as an ethernet device in OpenVZ. It is used inside a container and veth consists of MAC address. Veth uses bridged connection configurations with other devices to setup the networking between the two parties for the communication. It includes IPs and gateways to successfully setup the networking interface. This ethernet device contains two ports one is called as CT0 and another is CT. they are connected with each other and they work as interconnected device such that one's input is another's output.
Virtuozzo is an operating system that provides virtualization platform just like any other virtualization platform. It works well with the OpenVZ. It has it own containers that has the functionalities to provide the user with easiness and provide the environment in which management tools, recovery, etc can be incorporated. It provides the automation solution and built on top of OpenVZ.
The benefits of using virtuozzo are as follows:
Virtuozzo is a simple operating system to be used and managed. It allows the user to customize the platform using the built in management tools. It provides consistency between different platforms that are used. It maintains the tasks of different operating system together for easy maintenance and sharing. There are management tools that allow user to patch their product and if any difficulty can just upgrade the software version.
Physical to virtual tool for Linux is used while deploying virtuozzo. It is used a migration tool between physical and virtual machines. This makes it easy for the operating system to deploy all the necessary services and applications that are required by the operating system. It allows the testing processes to be migrated to ensure the performance and efficiency levels.
The density range talks about the resources of the server, content of the server and the virtual environment in which all the things are taking place. The two most important resources that are required by any virtualization platforms are CPU and RAM. The more the processing power the fewer requirements will be for the offload processing. Virtuozzo achieves a high density for example of 100 virtual environments as it has minimal content and applications when used with Linux operating system but when used with windows more resources is being taken up by windows operating system.
Virtuozzo allows one server that is dedicated to be split into multiple virtual servers and called as virtual environments. It doesn't add high amount of overhead but it keeps to minimal, as it adds only the native applications and operating system. It increases the performance by decreasing the overhead.
The disadvantages of using virtuozzo are as follows:
Virtual networks allow the creation and management of one or more virtual machines. It binds the container's virtual network adapter with the physical adapter that is associated with the network. It allows user to create virtual network on hardware node, remove an existing virtual network, and list all the networks that are present with their properties and configurations.
To enable the NAT services for virtuozzo container multiple servers has to be connected with the internet using the single IP address. The containers are running in host and bridged mode. NAT allows user to access the resources that are present on the internet. The command and properties combination that can be used to set the NAT for the container is
vzctl set 101 –nat on –save
This command will set the NAT for any container on the node. The 101 that is used is for a container that enables NAT for default virtual network adapter.
OpenVZ is a free and opensource portion of Virtuozzo. It includes core of Virtuozzo functionality, like kernel and command line management tools for creating and managing containers. Virtuozzo includes everything that OpenVZ does, plus additional features and services available with the commercial version only.
Previously, OpenVZ and Virtuozzo were built out of the same code base with some unique patches applied. That warranted the user interfaces to be similar but not identical. With Virtuozzo 7, the compatibility will be on the binary level - effectively the open source components will be the same between OpenVZ and Virtuozzo.
OpenVZ components will be undergoing the same testing procedures as the commercial product. Also, some new features previously available on Virtuozzo only (notably hypervisor) will become available on the product built for OpenVZ community users.
For the moment, only preview (beta) versions of Virtuozzo 7 are available. They are intended for development and testing only, not for production. Virtuozzo 7 is not yet commercially supported. For supported commercial version, please refer to Virtuozzo 6.
Our kernel developers work hard to merge containers functionality into the upstream Linux kernel, making OpenVZ team the biggest contributor to Linux Containers (LXC) kernel, with features such as PID and network namespaces, memory controller, checkpoint-restore and much more.
OpenVZ technology scales as well as standard Linux kernel — up to thousands of CPUs and terabytes of RAM.
There are two versions of OpenVZ available:
While there is no in-place upgrade, we prepared upgrade script for OpenVZ users to move their containers to the new platform. The script allows to transfer containers from old to new OpenVZ version (or from OpenVZ to Virtuozzo).