https://yanghu.github.io/tags/cups/Recent content in Cups on Yang's NotesHugo -- gohugo.ioen-usyang@yhu.me (Yang Hu)yang@yhu.me (Yang Hu)© 2026 Yang HuWed, 11 Mar 2026 00:00:00 -0800https://yanghu.github.io/posts/airprint-nas-setup/Wed, 11 Mar 2026 00:00:00 -0800yang@yhu.me (Yang Hu)https://yanghu.github.io/posts/airprint-nas-setup/<p>Runbook for setting up AirPrint on a Synology NAS so iOS/macOS devices can print to a USB or network printer over the local network. Uses a Docker CUPS container and Synology&rsquo;s built-in avahi (mDNS) daemon for service discovery.</p> <h2 class="relative group">Architecture <div id="architecture" class="anchor"></div> <span class="absolute top-0 w-6 transition-opacity opacity-0 -start-6 not-prose group-hover:opacity-100 select-none"> <a class="text-primary-300 dark:text-neutral-700 !no-underline" href="#architecture" aria-label="Anchor">#</a> </span> </h2> <div class="highlight-wrapper"><div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt"> 1 </span><span class="lnt"> 2 </span><span class="lnt"> 3 </span><span class="lnt"> 4 </span><span class="lnt"> 5 </span><span class="lnt"> 6 </span><span class="lnt"> 7 </span><span class="lnt"> 8 </span><span class="lnt"> 9 </span><span class="lnt">10 </span><span class="lnt">11 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-text" data-lang="text"><span class="line"><span class="cl">iPhone </span></span><span class="line"><span class="cl"> │ mDNS discovery (_ipp._tcp) </span></span><span class="line"><span class="cl"> ▼ </span></span><span class="line"><span class="cl">Synology avahi-daemon (eth4, port 5353) </span></span><span class="line"><span class="cl"> │ reads service files from /etc/avahi/services/ </span></span><span class="line"><span class="cl"> │ </span></span><span class="line"><span class="cl">CUPS Docker container (host network, port 631) </span></span><span class="line"><span class="cl"> │ generates /etc/avahi/services/AirPrint-*.service </span></span><span class="line"><span class="cl"> │ proxies print jobs to printer </span></span><span class="line"><span class="cl"> ▼ </span></span><span class="line"><span class="cl">Printer (e.g. socket://10.0.20.50:9100)</span></span></code></pre></td></tr></table> </div> </div></div> <p>Key design decisions:</p>