Skip to content

Xen and vserver: monitoring VMs on a PHP page

Introduction

I used this kind of script because it's simpler to open a small web page to view VM activity rather than launching a bunch of commands.

Sudo

You need sudo because by default Apache doesn't have the necessary rights to execute these commands:

1
apt-get install sudo

Then edit /etc/sudoers and add the following:

1
www-data        ALL=NOPASSWD: /usr/sbin/vserver-stat,/usr/sbin/xm list

Php and script

You obviously need to have Apache and PHP installed for this to work:

1
apt-get install apache2 php5

Additionally, there's a small JavaScript that refreshes the page every 60 seconds.

Then create a folder and copy this into an index file:

1
mkdir /var/www/virtual && vi /var/www/virtual/index.php

Here's the content of index.php:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <script language="javascript" type="text/javascript">
    setTimeout("location.reload();", 600000);
  </script>
  <head>
    <meta content="text/html; charset=ISO-8859-1" http-equiv="content-type" />
    <title>Informations for Virtual Machines</title>
  </head>
  <body>
    <?php
       system("date +%c") ;
       echo("<BR><br />--- Vservers informations ---<br />") ;
    echo("<syntaxhighlight lang="text"
      >\n") ; system("sudo /usr/sbin/vserver-stat") ; echo("</syntaxhighlight
    >\n") ; echo("<br />") ; echo("--- Xen informations ---<br />") ;
    echo("<syntaxhighlight lang="text"
      >\n") ; system("sudo /usr/sbin/xm list") ; echo("</syntaxhighlight
    >") ; ?>
  </body>
</html>

Now set the proper permissions:

1
chown -Rf www-data. /var/www/virtual

All that's left is to access it :-)