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.
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.
- ManageEngine VM Health Monitor 1.0
- An ESXi server
- 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:
Figure 2: Monitoring structure
1. Install Monitoring tool
a. Double click ManageEngine_VMHealthMonitor.exe
b. Follow the instructions in a typical Windows Installation
Figure 3: ManageEngine VM Health Monitor 1.0 installation
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:
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:
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.