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(General: added What applications can run inside an OpenVZ container?)
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{{Virtuozzo}}
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== General ==
 
== General ==
===== What is a container (Virtual Environment, Virtual Private Server, VPS, VE)? =====
 
:See [[Container]].
 
  
===== Who needs OpenVZ? How it can be used? =====
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===== So what is Virtuozzo? =====
:See [[Use cases]].
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Virtuozzo is a Linux based virtualization platform, combining container and hypervisor virtualization, into a single product. While primarily built for service providers to run cloud services and applications, it is used by variety of businesses, including MSP, SMB and Enterprises.
  
===== What applications can run inside an OpenVZ container? =====
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===== What is OpenVZ and how it compares to Virtuozzo? =====
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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.
  
Most of applications can be installed to a container without any modifications. Oracle, DB/2, Weblogic, Websphere and other big applications run just find inside an OpenVZ container. Applications and services do not have to be aware of OpenVZ. However, direct access to hardware is not available by default.
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===== How does Virtuozzo 7/OpenVZ pair compares to its predecessor (Virtuozzo versions 4.x and 6/OpenVZ) =====
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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.
  
===== How is OpenVZ different from other technologies? =====
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===== How OpenVZ users will benefit from it? =====
:See [[Introduction to virtualization]].
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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.
  
===== How is OpenVZ updated and why it is secure? =====
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===== What support options are available for Virtuozzo 7? =====
:See [[Security]].
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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 [http://www.odin.com/products/virtuozzo/ Virtuozzo 6].
  
===== I want to show my appreciation to OpenVZ and put some logo to my site. Where to get it? =====
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===== Why I need Virtuozzo/OpenVZ when LXC exist? =====
:See [[Artwork]].
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See our [[comparison]] of different virtualization solutions.
  
== Installation and upgrade ==
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===== When OpenVZ will be in upstream kernel? =====
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Our kernel developers [http://openvz.org/File:Kernel_patches_stats.png 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.
  
===== What hardware is supported by OpenVZ kernel? =====
 
:See [http://www.parallels.com/en/products/virtuozzo/hcl/ Virtuozzo HCL].
 
  
===== Why there are different kernel flavours available and what do they mean? =====
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===== I want to show my appreciation to OpenVZ and put some logo to my site. Where to get it? =====
:See [[Different kernel flavors (UP, SMP, ENTERPRISE, ENTNOSPLIT)]].
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:See [[Artwork]].
  
===== How do I rebuild the kernel? =====
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===== What kind of documentation is available? =====
:See [[Kernel build]].
 
  
===== What does 021stab018 in OpenVZ kernel version mean? =====
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:Aside from this wiki, which contains lots of information, you can check extensive [[Man|manual pages]] and [http://docs.openvz.org Virtuozzo documentation].
:See [[Kernel versioning]].
 
  
===== How can I check package signatures? =====
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===== Who needs OpenVZ? How it can be used? =====
:See [[Package signatures]].
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:See [[Use cases]].
  
===== Is it possible to run x86 container on a x86_64 arch? =====
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===== How scalable is OpenVZ? =====
:Sure :) We actually did some work on that to enable migration of x86 container from x86 to x86_64 and back, and to enable using 32-bit iptables in 32bit container on an x86_64 system.
 
  
===== What filesystems should I choose for saving my containers? =====
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OpenVZ technology scales as well as standard Linux kernel — up to thousands of CPUs and terabytes of RAM. Read more about [[WP/Containers_density|OpenVZ containers density]] and [[performance]].
: The safest choice is ext2/3 to save your containers. Remember that ReiserFS is less stable than ext2/3.
 
: If you choose to use XFS, there will be no support for disk quota inside containers.
 
  
== Networking ==
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== Installation and upgrade ==
  
===== How do I set up VPN for a container? =====
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===== How to install OpenVZ? =====
:See [[VPN via the TUN/TAP device]].
 
  
===== What is veth and how do I use it? =====
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There are two versions of OpenVZ available:
:See [[Virtual Ethernet device]].
 
  
===== Why doesn't net-snmpd work on my containers? =====
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* [[Roadmap|stable version]]: OpenVZ legacy (based on RHEL5 and RHEL6 kernels).
:See [[SNMPD in container]].
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* [[Roadmap|development version]]: [[Virtuozzo]] Linux distribution based on RHEL7 kernel.
  
== User Beancounters ==
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See [[Quick installation]]
  
===== What are those User Beancounters? =====
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===== What hardware is supported by OpenVZ kernel? =====
See [[UBC]].
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:See [https://hardware.redhat.com/ RHEL Hardware Compatibility List].
 
 
===== What units are UBC parameters measured in? =====
 
See [[UBC parameter units]].
 
 
 
===== How do I set up a container which is able to get X Mb of RAM? =====
 
See [[Setting UBC parameters]].
 
 
 
===== I can not start a program in container: it reports out of memory. What do I do? =====
 
See [[Resource_shortage]].
 
 
 
===== How can I reset <code>failcnt</code> in <code>/proc/user_beancounters</code>? =====
 
See [[UBC failcnt reset]].
 
 
 
== Troubleshooting ==
 
===== My kernel crashed. What should I do? =====
 
:See [[When you have an oops]].
 
 
 
===== I see a lot of processes in D state. What does that mean? =====
 
:See [[Processes in D state]].
 
  
== Quick reference card for OpenVZ ==
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===== How existing OpenVZ users can upgrade to the [[Virtuozzo|new version]]? =====
{{PDFlink|[http://pronics.fi/~eero/mirrors/openvz-reference-card.pdf openvz-reference-card.pdf]}}
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While there is no in-place upgrade, we prepared [[Upgrade_script_from_OpenVZ_to_Virtuozzo_7|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).

Latest revision as of 10:18, 9 January 2021

General[edit]

So what is Virtuozzo?[edit]

Virtuozzo is a Linux based virtualization platform, combining container and hypervisor virtualization, into a single product. While primarily built for service providers to run cloud services and applications, it is used by variety of businesses, including MSP, SMB and Enterprises.

What is OpenVZ and how it compares to Virtuozzo?[edit]

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.

How does Virtuozzo 7/OpenVZ pair compares to its predecessor (Virtuozzo versions 4.x and 6/OpenVZ)[edit]

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.

How OpenVZ users will benefit from it?[edit]

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.

What support options are available for Virtuozzo 7?[edit]

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.

Why I need Virtuozzo/OpenVZ when LXC exist?[edit]

See our comparison of different virtualization solutions.

When OpenVZ will be in upstream kernel?[edit]

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.


I want to show my appreciation to OpenVZ and put some logo to my site. Where to get it?[edit]
See Artwork.
What kind of documentation is available?[edit]
Aside from this wiki, which contains lots of information, you can check extensive manual pages and Virtuozzo documentation.
Who needs OpenVZ? How it can be used?[edit]
See Use cases.
How scalable is OpenVZ?[edit]

OpenVZ technology scales as well as standard Linux kernel — up to thousands of CPUs and terabytes of RAM. Read more about OpenVZ containers density and performance.

Installation and upgrade[edit]

How to install OpenVZ?[edit]

There are two versions of OpenVZ available:

See Quick installation

What hardware is supported by OpenVZ kernel?[edit]
See RHEL Hardware Compatibility List.
How existing OpenVZ users can upgrade to the new version?[edit]

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).