Asterisk Commands throught PHP script

<pre><table width="100%" style="border: 2px solid #CCCCCC;" cellpadding="3" cellspacing="3">
<tr bgcolor="#666666">
    <td align="center" background="stripe.png"><font color="#FFFFFF"><b><h1><?php system("hostname"); ?></h1></b></font></td>
  </tr>
  <tr bgcolor="#000000">
    <td><font color="#FFFFFF"><b>Uptime:</b></font></td>
  </tr>
  <tr bgcolor="#FFE4E1">
    <td><?php system("uptime"); ?></td>
  </tr>
  <tr bgcolor="#000000">
    <td><font color="#FFFFFF"><b>System Information:</b></font></td>
  </tr>
  <tr bgcolor="#FFDAB9">
    <td><?php system("uname -a"); ?></td>
  </tr>
 <tr bgcolor="#000000">
    <td><font color="#FFFFFF"><b>Memory Usage (MB):</b></font></td>
  </tr>
  <tr bgcolor="#FFF0F5">
    <td><?php system("free -m"); ?></td>
  </tr>
 <tr bgcolor="#000000">
    <td><font color="#FFFFFF"><b>Disk Usage:</b></font></td>
  </tr>
  <tr bgcolor="#E6E6FA">
    <td><?php system("df -h"); ?></td>
  </tr>
 <tr bgcolor="#000000">
    <td><font color="#FFFFFF"><b>CPU Information:</b></font></td>
  </tr>
  <tr bgcolor="#F0FFF0">
    <td><?php system("cat /proc/cpuinfo | grep \"model name\\|processor\""); ?></td>
  </tr>
</table>

</pre>