https://yy-tech.online/zh/categories/linux/ Recent content in Linux on H&W Hugo zh-Hant Thu, 28 May 2026 00:53:02 +0800 https://yy-tech.online/zh/post/play-with-contab/ Mon, 07 Aug 2017 12:33:21 +0800 https://yy-tech.online/zh/post/play-with-contab/ <h2 id="如何查日志">如何查日志</h2> <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-shell" data-lang="shell"><span class="line"><span class="cl">sudo /var/log/syslog <span class="p">|</span> grep cron </span></span></code></pre></td></tr></table> </div> </div><h2 id="捕获输出">捕获输出</h2> <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-shell" data-lang="shell"><span class="line"><span class="cl"><span class="m">1</span> <span class="m">2</span> * * * /home/hyy/Start.py &gt;/tmp/output.log 2&gt;<span class="p">&amp;</span><span class="m">1</span> </span></span></code></pre></td></tr></table> </div> </div><h2 id="确认-cron-在跑">确认 cron 在跑</h2> <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-shell" data-lang="shell"><span class="line"><span class="cl">ps -ef <span class="p">|</span> grep cron <span class="p">|</span> grep -v grep </span></span></code></pre></td></tr></table> </div> </div><h2 id="路径要对">路径要对</h2> <ul> <li>crontab 默认在 <code>$HOME</code> 下执行；若脚本里用 <code>os.getcwd()</code>，目录不对会报找不到模块。</li> <li>命令里尽量写<strong>绝对路径</strong>，或在任务前 <code>source ~/.zshrc</code>，保证环境变量可用。</li> </ul> <h2 id="最后一行要空行">最后一行要空行</h2> <ul> <li>很多人踩坑：crontab 文件<strong>末尾需要空行</strong>，否则最后一条可能不执行。</li> </ul> <h2 id="debianubuntu-的权限与命名">Debian/Ubuntu 的权限与命名</h2> <p><code>/etc/cron.d</code> 及 <code>cron.{hourly,daily,weekly,monthly}</code> 下的文件需满足：</p>