https://nerdsid.com/tags/systemd/Recent content in systemd on Nerdsid.comHugoen-usWed, 15 Apr 2026 06:39:17 +0000https://nerdsid.com/posts/linux-journalctl-cheatsheet/Wed, 15 Apr 2026 06:39:17 +0000https://nerdsid.com/posts/linux-journalctl-cheatsheet/<p>I recently needed to free up disk space by removing old system logs, so I collected the command I used and other useful journalctl commands for future reference.</p> <h2 id="disk-usage--vacuum-remove-old-logs">Disk usage &amp; vacuum (remove old logs)</h2> <p>Show journal disk usage:</p> <div class="codeblock"> <div class="codeblock__header"> <div class="codeblock__filename codeblock__filename--lang"> BASH </div> <div class="codeblock__actions"> </div> </div> <div class="codeblock__body"> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">sudo journalctl --disk-usage</span></span></code></pre></div> </div> </div><p>Remove archived journal files until total size is below X:</p> <div class="codeblock"> <div class="codeblock__header"> <div class="codeblock__filename codeblock__filename--lang"> BASH </div> <div class="codeblock__actions"> </div> </div> <div class="codeblock__body"> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">sudo journalctl --vacuum-size<span class="o">=</span>500M</span></span></code></pre></div> </div> </div><p>Remove archived journal files older than a time:</p> <div class="codeblock"> <div class="codeblock__header"> <div class="codeblock__filename codeblock__filename--lang"> BASH </div> <div class="codeblock__actions"> </div> </div> <div class="codeblock__body"> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">sudo journalctl --vacuum-time<span class="o">=</span>3d</span></span></code></pre></div> </div> </div><p>Remove archived journal files, keeping only the most recent N files:</p>