/blog/tags/rant/ falkp.no/blog (Rant) Hugo -- gohugo.io en-us Tue, 31 May 2016 00:00:00 +0000 /blog/posts/using_finger_service_the_wrong_way/ Tue, 31 May 2016 00:00:00 +0000 /blog/posts/using_finger_service_the_wrong_way/ <h2 id="overview" > <div> <a href="#overview"> # </a> Overview </div> </h2> <p>If you&rsquo;re doing this, you&rsquo;re doing it wrong&hellip;:</p> <pre tabindex="0"><code>2016-05-31 10:19:45.493314 Client 92.x.x.192 hamburg, germany/hamburg/hamburg 2016-05-31 10:19:48.443380 Client 74.x.x.189 greensboro, united_states/north_carolina/greensboro 2016-05-31 10:19:56.733260 Client 50.x.x.50 beaverton, united_states/oregon/beaverton 2016-05-31 10:19:56.745653 Client 50.x.x.50 beaverton, united_states/oregon/beaverton 2016-05-31 10:19:56.759656 Client 50.x.x.50 beaverton, united_states/oregon/beaverton 2016-05-31 10:19:56.819283 Client 50.x.x.50 beaverton, united_states/oregon/beaverton 2016-05-31 10:20:16.287744 Client 5.x.x.13 kaiserslautern, germany/rhineland-palatinate/kaiserslautern 2016-05-31 10:20:35.182942 Client 85.x.x.140 katowice, poland/silesia/katowice 2016-05-31 10:20:47.029550 Client 193.x.x.226 oslo, norway/oslo/oslo/oslo </code></pre><p>Lots of people use the finger service <strong>@graph.no</strong> in an automated way. That&rsquo;s quite alright, it&rsquo;s what it&rsquo;s there for. As an example:</p> <p><img src="sd_full.jpg" alt="@graph.no used in an automated way at the Computer Science department at the KIT Karlsruhe"></p> <p>But if you&rsquo;re asking for the same data five times a second (until you get blocked by my firewall for a minute), you have to check your code. The data is at best changing every ~30 minutes.</p> <p>A likely scenario is putting it in <strong>screen</strong>/<strong>tmux</strong> status line. If you do that, you need to change how often your terminal multiplexer is updating the status line. A better way is to have a cron script fetching the data, and storing it in i.e. <code>/tmp/weather</code> every 30-60 minutes, and then have your status line read from that.</p> <p>Another scenario could be people running it in <strong>watch</strong>, which by default updates every two seconds. Also wrong. Please use -n 600 more.</p> <p>If you fetch the data, and <strong>grep</strong> out what you need, then fetch the data once, and <strong>grep</strong> all you like. Don&rsquo;t fetch for each <strong>grep</strong>. An example of this can be seen in the client <a href="https://github.com/ways/pyyrascii/blob/master/graph.sh">graph.sh</a>, which fetches the data, <strong>sed</strong> a lot and present it using unicode weather symbols and colors.</p> <p>Feel free to contact me if you need scripts/examples or have questions.</p> <p>Also, don&rsquo;t feel ashamed, beaverton, you&rsquo;re not alone in hammering me. I just don&rsquo;t have any way to contact users. I still love you all. =)</p>