Free VI3 monitoring tool – Unnoc
March 14th, 2008 | 
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Leo Raikhman left me a comment, which lead me to his Leo’s Ramblings blog, which in turn, taught me about another open source monitoring tool for VI3 called Unnoc. In his post Using unnoc to monitor your ESX servers Leo explains why Unnoc is his favorite over other open source monitoring solutions:
“Let me just say that I hate complicated configurations which is why I immediately discarded cacti and nagios – the other two contenders for free ESX monitoring. Also, having used both, the complexity of their data gathering left a lot to be desired. Unnoc is simple and it works because it was designed to do a limited number of things.”
Leo’s post walks you through the installation and configuration of Unnoc on Ubuntu.
Here’s more about the tool From Unnoc.org:
Unnoc is a NOC network monitoring application that is designed to integrate traffic graphs (RRDTool) with SNMP host checking, monitoring and graphing. It uses native SNMP to monitor servers, Wireless Access Points, UPS’s, routers, firewalls, network switches–anything SNMP-enabled, and will send out pages and email alerts if something is wrong
VMware Virtual Infrastructure 3
Added in 1.0.7, VMware Virtual Infrastructure 3 has been added. This means you can graph ESX utilization as well as track all of your Virtual Machines. It currently graphs the following:
Click here to see a working demo of this.
- ESX Memory Usage
- ESX CPU Usage
- ESX Network Bandwidth Usage
- ESX Disk Access Usage (read/write counters)
- ESX Console statistics (via SNMP)
- VM Memory Usage
- VM CPU Usage
- VM Network Bandwidth Usage
- VM Disk Access Usage (read/write counters)
- VM Power States (suspended/off/on)
- VirtualCenter Console statistics (via SNMP)This plugin is one of the exceptions: it does not use SNMP. Instead, the VI Perl Toolkit was used, which uses the SDK provided by VMware:
http://sourceforge.net/projects/viperltoolkit/
Why not SNMP for VMware ESX / VI3?
VMware does actually provide a MIB available with ESX, and it does display much information about all of the VM’s and the ESX server itself. There were a few problems with it, for one the information wasn’t updated in real time (it seemed to be caching quite a bit of data), which presented its own problems. But the main issue at hand was that not all information was available through SNMP. Specifically, CPU usage and CPU Mhz wasnt available. They do provide a cpuUtil counter, however that is milliseconds used by each VM, and given that value you could calculate a percentage of Real CPU based on the amount of time passed in between each read. However this did not prove to be 100% accurate, and I would get very large spikes every now and then. CPU Mhz wasn’t available either, so you can not tell how many cycles are available total. Another reason is the counters that were provided for disk I/O and ethernet were not always 100% accurate. They would often times just mimic each other. I’m not sure why it didn’t work like it
was supposed to, but it didn’t. So instead, the plugin was written with the VI Perl Toolkit. This is better for a few reasons, not only because it gives you access to the exact same information as the VI3 client or the MUI has, but more importantly it allows you to connect to a VirtualCenter server and read all of the information from there. VI3 is designed to be used with a VCMS server, so it only makes sense to connect to it for all information. If you do not use a VCMS server, it will still work just the same with an ESX standalone server.Currently it is monitoring CPU Usage, Memory, Disk I/O, and Ethernet Traffic. In the future there will be Resource Pools as well.
You can also get Unnoc as a downloadable virtual appliance from VMware’s Virtual Appliance Marketplace
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Posted in esx, how to, vmetc.com | 
Tags: esx, hp, monitoring, opensource, ubuntu, virtualcenter, vmware
Unnoc rocks ! Very easy to get up and running and tells you what you want to know with a minumum of fuss.