nixpkgs/nixos/doc/manual/from_md/installation/obtaining.chapter.xml

<chapter xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xml:id="sec-obtaining">
  <title>Obtaining NixOS</title>
  <para>
    NixOS ISO images can be downloaded from the
    <link xlink:href="https://nixos.org/download.html#nixos-iso">NixOS
    download page</link>. Follow the instructions in
    <xref linkend="sec-booting-from-usb" /> to create a bootable USB
    flash drive.
  </para>
  <para>
    If you have a very old system that can’t boot from USB, you can burn
    the image to an empty CD. NixOS might not work very well on such
    systems.
  </para>
  <para>
    As an alternative to installing NixOS yourself, you can get a
    running NixOS system through several other means:
  </para>
  <itemizedlist>
    <listitem>
      <para>
        Using virtual appliances in Open Virtualization Format (OVF)
        that can be imported into VirtualBox. These are available from
        the
        <link xlink:href="https://nixos.org/download.html#nixos-virtualbox">NixOS
        download page</link>.
      </para>
    </listitem>
    <listitem>
      <para>
        Using AMIs for Amazon’s EC2. To find one for your region, please
        refer to the
        <link xlink:href="https://nixos.org/download.html#nixos-amazon">download
        page</link>.
      </para>
    </listitem>
    <listitem>
      <para>
        Using NixOps, the NixOS-based cloud deployment tool, which
        allows you to provision VirtualBox and EC2 NixOS instances from
        declarative specifications. Check out the
        <link xlink:href="https://nixos.org/nixops">NixOps
        homepage</link> for details.
      </para>
    </listitem>
  </itemizedlist>
</chapter>