How to monitor VMware ESXi with VM Health Monitor

ESXi is a virtualization software by VMware that is installed directly on hardware. It can host Virtual Machines without the need of a host operating system, thus improving performance and allowing the users to customize the options more deeply.

VMware ESXi 5.5.0 system info

Figure 1: ESXi 5.5.0

When it comes to monitor ESXi, there are several options, from monitoring it through configurations and built-in counters, to third party software. This time I’ll write about monitoring with a third party application, mostly because of the ease of use and the time needed from the final user to set the test environment. Also, this is one of the simplest monitoring tools available, and it’s free. In this case, you don’t need to download extra tools to manage the ESXi server, which is an advantage when testing.



    In general, it could be said that the most important variables to be taken into account when monitoring an ESXi server are the following:
  • CPU utilization
  • Memory utilization
  • Disk Read
  • Disk Write
  • Rate at which data is received (Network)
  • Rate at which data is transmitted (Network)

In this example, these variables will be collected from an ESXi server to monitor its performance. The basic structure for monitoring is the following:CPU utilization, Memory utilization, Disk Read and write monitoring on ESXi server

Figure 2: Monitoring structure


1. Install Monitoring tool
   a. Double click ManageEngine_VMHealthMonitor.exe
   b. Follow the instructions in a typical Windows Installation
Free VM Health Monitor Setup process

Figure 3: ManageEngine VM Health Monitor 1.0 installation

Free VM Health Monitor configuration. Step 1 - ManageEngine main screen

Figure 4: ManageEngine main screen

After the installation finishes, you’ll see a screen like this:
   c. Fill all the required fields for one of the Hosts and click Connect. You can use the following example to fill the data:
Free VM Health Monitor configuration. Step 2 - getting ESXi server data

Figure 5: ESXi server data

In this case, I used the default port (443) and the “root” user. The thresholds for CPU were left as default. After that, you’ll see a simple dialog showing the monitoring data as follows:
ESXi server metrics monitoring

Figure 6: ESXi server metrics

As you can see, all the needed parameters are monitored in real time. Refresh time is 15 minutes by default, but there is the possibility to refresh data whenever is needed. As with any other monitoring tool or method, the real value of the metrics is the way they are understood by the monitoring responsible.

Some notes about testing environments

    If you are just want to test this or any other monitoring method for ESXi, you should take into account some details:
  • If you want to install ESXi as a Virtual Machine, you need to use VMware Workstation 9 or higher.
  • Remember that ESXi represents a heavy load of memory and CPU usage.
  • A 64 bit architecture is recommended.
  • You need a processor with Hardware Virtualization Support enabled. You can check it in the BIOS, or you can use the Microsoft® Hardware-Assisted Virtualization Detection Tool. This tool is not supported by Windows 8.
  • Additional configurations are needed in order to run Virtual Machines on an ESXi server hosted in a Virtual machines. You can consult this source for more information.