title: 'No package protobuf-devel available' error on centos 7
body: <p>I tried to use yum to install protobuf-devel on CentOS7, but it gives me this error:</p>
  
  <pre><code>No package protobuf-devel available
  </code></pre>
  
  <p>I didn't change yum resources, just use a proxy of my company, can I fix this problem rather than installing protobuf via source?</p>