title: HTTP GET requests being made to my website for unknown .php files. Why and how to prevent this
body: <p>I have an application deployed on a digital ocean droplet.  About 1 day after deploying, my server crashed, the final logs look like this:</p>
  
  <pre><code>GET /vehicle/tank/all/1 304 2.965 ms - -
  GET /vehicle/tank/all/1 304 2.582 ms - -
  GET /vehicle/tank/all/1 304 1.735 ms - -
  GET /vehicle/tank/all/1 304 1.566 ms - -
  GET http://dhg.pisz.pl/httptest.php 404 1.771 ms - 43
  GET http://dhg.pisz.pl/httptest.php 404 3.271 ms - 43
  GET http://dhg.pisz.pl/httptest.php 404 1.051 ms - 43
  GET http://24x7-allrequestsallowed.com/?  PHPSESSID=aab45f4f00143PWZJTVBY%40DXJFV%5D 200 1.777 ms - 1878
  GET / 200 2.794 ms - 1878
  GET http://testp4.pospr.waw.pl/testproxy.php 404 2.617 ms - 52
  HEAD /robots.txt 404 2.946 ms - 24
  HEAD / 200 1.751 ms - 1878
  GET http://dhg.pisz.pl/httptest.php 404 9.679 ms - 43
  
  Error: Connection lost: The server closed the connection.
  at Protocol.end (/root/tycho/node_modules/mysql/lib/protocol/Protocol.js:109:13)
  at Socket.&lt;anonymous&gt; (/root/tycho/node_modules/mysql/lib/Connection.js:102:28)
  at Socket.EventEmitter.emit (events.js:117:20)
  at _stream_readable.js:920:16
  at process._tickCallback (node.js:415:13)
  [nodemon] app crashed - waiting for file changes before starting...
  </code></pre>
  
  <p>Is this an attack? If so, what can I do to prevent a client from making these types of get requests in the first place?  </p>