libvirt/docs/drvhyperv.html.in
Matt Coleman c0939b4e56 hyperv: implement connectGetVersion
Hyper-V version numbers are not compatible with the encoding in
virParseVersionString():
https://gitlab.com/libvirt/libvirt/-/blob/master/src/util/virutil.c#L246

For example, the Windows Server 2016 Hyper-V version is 10.0.14393: its
micro is over 14 times larger than the encoding allows.

This commit repacks the Hyper-V version number in order to preserve all
of the digits. The major and minor are concatenated (with minor zero-
padded to two digits) to form the repacked major value. This works
because Microsoft's major and minor versions numbers are unlikely to
exceed 99. The repacked minor value is derived from the digits in the
thousands, ten-thousands, and hundred-thousands places of Hyper-V's
micro. The repacked micro is derived from the digits in the ones, tens,
and hundreds places of Hyper-V's micro.

Co-authored-by: Sri Ramanujam <sramanujam@datto.com>
Signed-off-by: Matt Coleman <matt@datto.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-10-09 09:27:20 +02:00

166 lines
5.1 KiB
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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<h1>Microsoft Hyper-V hypervisor driver</h1>
<ul id="toc"></ul>
<p>
The libvirt Microsoft Hyper-V driver can manage Hyper-V 2008 R2 and newer.
</p>
<h2><a id="project">Project Links</a></h2>
<ul>
<li>
The <a href="http://www.microsoft.com/hyper-v-server/">Microsoft Hyper-V</a>
hypervisor
</li>
</ul>
<h2><a id="uri">Connections to the Microsoft Hyper-V driver</a></h2>
<p>
Some example remote connection URIs for the driver are:
</p>
<pre>
hyperv://example-hyperv.com (over HTTPS)
hyperv://example-hyperv.com/?transport=http (over HTTP)
</pre>
<p>
<strong>Note</strong>: In contrast to other drivers, the Hyper-V driver
is a client-side-only driver. It connects to the Hyper-V server using
WS-Management over HTTP(S). Therefore, the
<a href="remote.html">remote transport mechanism</a> provided by the
remote driver and libvirtd will not work, and you cannot use URIs like
<code>hyperv+ssh://example.com</code>.
</p>
<h3><a id="uriformat">URI Format</a></h3>
<p>
URIs have this general form (<code>[...]</code> marks an optional part).
</p>
<pre>
hyperv://[username@]hostname[:port]/[?extraparameters]
</pre>
<p>
The default HTTPS ports is 5986. If the port parameter is given, it
overrides the default port.
</p>
<h4><a id="extraparams">Extra parameters</a></h4>
<p>
Extra parameters can be added to a URI as part of the query string
(the part following <code>?</code>). A single parameter is formed by a
<code>name=value</code> pair. Multiple parameters are separated by
<code>&amp;</code>.
</p>
<pre>
?transport=http
</pre>
<p>
The driver understands the extra parameters shown below.
</p>
<table class="top_table">
<tr>
<th>Name</th>
<th>Values</th>
<th>Meaning</th>
</tr>
<tr>
<td>
<code>transport</code>
</td>
<td>
<code>http</code> or <code>https</code>
</td>
<td>
Overrides the default HTTPS transport. The default HTTP port
is 5985.
</td>
</tr>
</table>
<h3><a id="auth">Authentication</a></h3>
<p>
In order to perform any useful operation the driver needs to log into
the Hyper-V server. Therefore, only <code>virConnectOpenAuth</code> can
be used to connect to an Hyper-V server, <code>virConnectOpen</code> and
<code>virConnectOpenReadOnly</code> don't work.
To log into an Hyper-V server the driver will request credentials using
the callback passed to the <code>virConnectOpenAuth</code> function.
The driver passes the hostname as challenge parameter to the callback.
</p>
<p>
<strong>Note</strong>: Currently only <code>Basic</code> authentication
is supported by libvirt. This method is disabled by default on the
Hyper-V server and can be enabled via the WinRM commandline tool.
</p>
<pre>
winrm set winrm/config/service/auth @{Basic="true"}
</pre>
<p>
To allow <code>Basic</code> authentication with HTTP transport WinRM
needs to allow unencrypted communication. This can be enabled via the
WinRM commandline tool. However, this is not the recommended
communication mode.
</p>
<pre>
winrm set winrm/config/service @{AllowUnencrypted="true"}
</pre>
<h2><a id="versions">Version Numbers</a></h2>
<p>
Since Microsoft's build numbers are almost always over 1000, this driver
needs to pack the value differently compared to the format defined by
<code>virConnectGetVersion</code>.
To preserve all of the digits, the following format is used:
</p>
<pre>major * 100000000 + minor * 1000000 + micro</pre>
<p>
This results in <code>virsh version</code> producing unexpected output.
</p>
<table class="top_table">
<thead>
<th>Windows Release</th>
<th>Kernel Version</th>
<th>libvirt Representation</th>
</thead>
<tr>
<td>Windows Server 2008</td>
<td>6.0.6001</td>
<td>600.6.1</td>
</tr>
<tr>
<td>Windows Server 2008 R2</td>
<td>6.1.7600</td>
<td>601.7.600</td>
</tr>
<tr>
<td>Windows Server 2012</td>
<td>6.2.9200</td>
<td>602.9.200</td>
</tr>
<tr>
<td>Windows Server 2012 R2</td>
<td>6.3.9600</td>
<td>603.9.600</td>
</tr>
<tr>
<td>Windows Server 2016</td>
<td>10.0.14393</td>
<td>1000.14.393</td>
</tr>
<tr>
<td>Windows Server 2019</td>
<td>10.0.17763</td>
<td>1000.17.763</td>
</tr>
</table>
</body></html>