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installation.html

@@ -212,37 +212,34 @@ job or scheduled task.</p>
 <section id="installing-parsedmarc">
 <h2>Installing parsedmarc<a class="headerlink" href="#installing-parsedmarc" title="Link to this heading"></a></h2>
 <p>On Debian or Ubuntu systems, run:</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>apt-get<span class="w"> </span>install<span class="w"> </span>-y<span class="w"> </span>python3-pip<span class="w"> </span>python3-virtualenv<span class="w"> </span>python3-dev<span class="w"> </span>libxml2-dev<span class="w"> </span>libxslt-dev
+<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>apt-get<span class="w"> </span>install<span class="w"> </span>-y<span class="w"> </span>python3-pip<span class="w"> </span>python3-venv<span class="w"> </span>python3-dev<span class="w"> </span>libxml2-dev<span class="w"> </span>libxslt-dev
 </pre></div>
 </div>
 <p>On CentOS or RHEL systems, run:</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>dnf<span class="w"> </span>install<span class="w"> </span>-y<span class="w"> </span>python39<span class="w"> </span>python3-virtualenv<span class="w"> </span>python3-setuptools<span class="w"> </span>python3-devel<span class="w"> </span>libxml2-devel<span class="w"> </span>libxslt-devel
+<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>dnf<span class="w"> </span>install<span class="w"> </span>-y<span class="w"> </span>python3<span class="w"> </span>python3-pip<span class="w"> </span>python3-devel<span class="w"> </span>libxml2-devel<span class="w"> </span>libxslt-devel
 </pre></div>
 </div>
 <p>Python 3 installers for Windows and macOS can be found at
 <a class="reference external" href="https://www.python.org/downloads/">https://www.python.org/downloads/</a>.</p>
-<p>Create a system user</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>mkdir<span class="w"> </span>/opt
-sudo<span class="w"> </span>useradd<span class="w"> </span>parsedmarc<span class="w"> </span>-r<span class="w"> </span>-s<span class="w"> </span>/bin/false<span class="w"> </span>-m<span class="w"> </span>-b<span class="w"> </span>/opt
+<p><code class="docutils literal notranslate"><span class="pre">parsedmarc</span></code> requires Python 3.10 or newer. If your distribution’s
+default <code class="docutils literal notranslate"><span class="pre">python3</span></code> is older, install a newer interpreter (e.g.
+<code class="docutils literal notranslate"><span class="pre">python3.12</span></code>) and substitute it for <code class="docutils literal notranslate"><span class="pre">python3</span></code> in the commands below.</p>
+<p>Create a dedicated system user, with <code class="docutils literal notranslate"><span class="pre">/opt/parsedmarc</span></code> as its home
+directory so the directory is created with the correct ownership in
+the same step</p>
+<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>useradd<span class="w"> </span>--system<span class="w"> </span>--create-home<span class="w"> </span>--home-dir<span class="w"> </span>/opt/parsedmarc<span class="w"> </span><span class="se">\</span>
+<span class="w">    </span>--shell<span class="w"> </span>/usr/sbin/nologin<span class="w"> </span>--skel<span class="w"> </span>/dev/null<span class="w"> </span>parsedmarc
 </pre></div>
 </div>
-<p>Install parsedmarc in a virtualenv</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>-u<span class="w"> </span>parsedmarc<span class="w"> </span>virtualenv<span class="w"> </span>/opt/parsedmarc/venv
-</pre></div>
-</div>
-<p>CentOS/RHEL 8 systems use Python 3.6 by default, so on those systems
-explicitly tell <code class="docutils literal notranslate"><span class="pre">virtualenv</span></code> to use <code class="docutils literal notranslate"><span class="pre">python3.10</span></code> instead</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>-u<span class="w"> </span>parsedmarc<span class="w"> </span>virtualenv<span class="w"> </span>-p<span class="w"> </span>python3.10<span class="w">  </span>/opt/parsedmarc/venv
-</pre></div>
-</div>
-<p>Activate the virtualenv</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="nb">source</span><span class="w"> </span>/opt/parsedmarc/venv/bin/activate
-</pre></div>
-</div>
-<p>To install or upgrade <code class="docutils literal notranslate"><span class="pre">parsedmarc</span></code> inside the virtualenv, run:</p>
-<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>-u<span class="w"> </span>parsedmarc<span class="w"> </span>/opt/parsedmarc/venv/bin/pip<span class="w"> </span>install<span class="w"> </span>-U<span class="w"> </span>parsedmarc
+<p>Create a virtualenv and install <code class="docutils literal notranslate"><span class="pre">parsedmarc</span></code> into it as that user, so
+any files created later are also owned by <code class="docutils literal notranslate"><span class="pre">parsedmarc</span></code></p>
+<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span>sudo<span class="w"> </span>-u<span class="w"> </span>parsedmarc<span class="w"> </span>python3<span class="w"> </span>-m<span class="w"> </span>venv<span class="w"> </span>/opt/parsedmarc/venv
+sudo<span class="w"> </span>-u<span class="w"> </span>parsedmarc<span class="w"> </span>/opt/parsedmarc/venv/bin/pip<span class="w"> </span>install<span class="w"> </span>--upgrade<span class="w"> </span>pip
+sudo<span class="w"> </span>-u<span class="w"> </span>parsedmarc<span class="w"> </span>/opt/parsedmarc/venv/bin/pip<span class="w"> </span>install<span class="w"> </span>--upgrade<span class="w"> </span>parsedmarc
 </pre></div>
 </div>
+<p>To upgrade <code class="docutils literal notranslate"><span class="pre">parsedmarc</span></code> later, re-run the last command above and then
+restart the service.</p>
 </section>
 <section id="optional-dependencies">
 <h2>Optional dependencies<a class="headerlink" href="#optional-dependencies" title="Link to this heading"></a></h2>