update link qemu documentation non web.archive

[pve-docs.git] / pve-faq.adoc

Frequently Asked Questions
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NOTE: New FAQs are appended to the bottom of this section.

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ADD NEW FAQS TO THE BOTTOM OF THIS SECTION TO MAINTAIN NUMBERING
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[qanda]

What distribution is {pve} based on?::

{pve} is based on http://www.debian.org[Debian GNU/Linux]

What license does the {pve} project use?::

{pve} code is licensed under the GNU Affero General Public License,
version 3.

Will {pve} run on a 32bit processor?::

{pve} works only on 64-bit CPUs (AMD or Intel). There is no plan
for 32-bit for the platform.
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NOTE: VMs and Containers can be both 32-bit and 64-bit.

Does my CPU support virtualization?::

To check if your CPU is virtualization compatible, check for the `vmx`
or `svm` tag in this command output:
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----
egrep '(vmx|svm)' /proc/cpuinfo
----

Supported Intel CPUs::

64-bit processors with
http://en.wikipedia.org/wiki/Virtualization_Technology#Intel_virtualization_.28VT-x.29[Intel
Virtualization Technology (Intel VT-x)] support. (http://ark.intel.com/search/advanced/?s=t&VTX=true&InstructionSet=64-bit[List of processors with Intel VT and 64-bit])

Supported AMD CPUs::

64-bit processors with
http://en.wikipedia.org/wiki/Virtualization_Technology#AMD_virtualization_.28AMD-V.29[AMD
Virtualization Technology (AMD-V)] support.

What is a container/virtual environment (VE)/virtual private server (VPS)?::

In the context of containers, these terms all refer to the concept of
operating-system-level virtualization. Operating-system-level virtualization is
a method of virtualization, in which the kernel of an operating system
allows for multiple isolated instances, that all share the kernel. When
referring to LXC, we call such instances containers. Because containers use the
host's kernel rather than emulating a full operating system, they require less
overhead, but are limited to Linux guests.

What is a QEMU/KVM guest (or VM)?::

A QEMU/KVM guest (or VM) is a guest system running virtualized under
{pve} using QEMU and the Linux KVM kernel module.

What is QEMU?::

QEMU is a generic and open source machine emulator and
virtualizer. QEMU uses the Linux KVM kernel module to achieve near
native performance by executing the guest code directly on the host
CPU.
It is not limited to Linux guests but allows arbitrary operating systems
to run.

[[faq-support-table]]
How long will my {pve} version be supported?::

{pve} versions are supported at least as long as the corresponding
Debian Version is
https://wiki.debian.org/DebianOldStable[oldstable]. {pve} uses a
rolling release model and using the latest stable version is always
recommended.
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[width="100%",cols="5*d",options="header"]
|===========================================================
| {pve} Version | Debian Version    | First Release | Debian EOL | Proxmox EOL
| {pve} 6.x     | Debian 10 (Buster)| 2019-07       | tba        | tba
| {pve} 5.x     | Debian 9 (Stretch)| 2017-07       | 2020-07    | 2020-07
| {pve} 4.x     | Debian 8 (Jessie) | 2015-10       | 2018-06    | 2018-06
| {pve} 3.x     | Debian 7 (Wheezy) | 2013-05       | 2016-04    | 2017-02
| {pve} 2.x     | Debian 6 (Squeeze)| 2012-04       | 2014-05    | 2014-05
| {pve} 1.x     | Debian 5 (Lenny)  | 2008-10       | 2012-03    | 2013-01
|===========================================================

[[faq-upgrade]]
How can I upgrade {pve} to the next release?::

Minor version upgrades, for example upgrading from {pve} in version 5.1
to 5.2, can be done just like any normal update, either through the Web
GUI __Node -> Updates__ panel or through the CLI with:
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----
apt update
apt full-upgrade
----
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NOTE: Always ensure you correctly setup the
xref:sysadmin_package_repositories[package repositories] and only
continue with the actual upgrade if `apt update` did not hit any error.
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Major version upgrades, for example going from {pve} 4.4 to 5.0, are
also supported. They must be carefully planned and tested and should
*never* be started without having a current backup ready.
Although the specific upgrade steps depend on your respective setup, we
provide general instructions and advice of how a upgrade should be
performed:
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* https://pve.proxmox.com/wiki/Upgrade_from_5.x_to_6.0[Upgrade from {pve} 5.x to 6.0]

* https://pve.proxmox.com/wiki/Upgrade_from_4.x_to_5.0[Upgrade from {pve} 4.x to 5.0]

* https://pve.proxmox.com/wiki/Upgrade_from_3.x_to_4.0[Upgrade from {pve} 3.x to 4.0]

LXC vs LXD vs Proxmox Containers vs Docker::

LXC is a userspace interface for the Linux kernel containment
features. Through a powerful API and simple tools, it lets Linux users
easily create and manage system containers. LXC, as well as the former
OpenVZ, aims at *system virtualization*. Thus, it allows you to run a
complete OS inside a container, where you log in using ssh, add users,
run apache, etc...
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LXD is built on top of LXC to provide a new, better user
experience. Under the hood, LXD uses LXC through `liblxc` and its Go
binding to create and manage the containers. It's basically an
alternative to LXC's tools and distribution template system with the
added features that come from being controllable over the network.
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Proxmox Containers are how we refer to containers that are created and managed
using the Proxmox Container Toolkit (`pct`). They also target *system
virtualization* and use LXC as the basis of the container offering. The
Proxmox Container Toolkit (`pct`) is tightly coupled with {pve}. This means
that it is aware of cluster setups, and it can use the same network
and storage resources as QEMU virtual machines (VMs). You can even use the
{pve} firewall, create and restore backups, or manage containers using
the HA framework. Everything can be controlled over the network using
the {pve} API.
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Docker aims at running a *single* application in an isolated, self-contained
environment. These are generally referred to as ``Application Containers'', rather
than ``System Containers''. You manage a Docker instance from the host, using the
Docker Engine command line interface. It is not recommended to run docker
directly on your {pve} host.
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NOTE: If you want to run application containers, for example, 'Docker' images, it
is best to run them inside a Proxmox Qemu VM.