title: yum install command fails for db4-devel
body: <p>I tried to do this command on my Ubuntu machine:</p>
  
  <pre><code>yum install db4-devel
  </code></pre>
  
  <p>However I get an error message telling me that the URL could not be parsed correctly. I guess I have to get db4-devel somehow first, but how do I do this?</p>