In ESX classic the VMware agents (hostd, vpxa), virtual machine monitor and the various 3rd party agents run in the service console. In ESXi, they run natively within VMkernel. This architecture does not allow for installing any arbitrary code on your ESXi system (hence improving security and stability of the product). How then, can we plug in a monitoring solution?
Hardware Monitoring on ESXi
The Common Information Model (CIM) is used on ESXi instead of installing the hardware agents in the Service Console. The different CIM providers are available for different hardware installed in the server (HBA, Network cards, Raid Controllers etc).
These CIM providers monitor the hardware and provide the status to a CIM Broker. The CIM broker takes information from all CIM providers and presents it to the outside world via standard APIs, such as WS-MAN client. Any software tool that understands one of these APIs, such as HP SIM or Dell OpenManage, can read this information and hence monitor the hardware of the ESXi host.
VMware vCenter server is capable of presenting this information through the Hardware Status tab, where it provides all the hardware information. This option was introduced in ESXi 3.5 and now has been enhanced in ESXi 4 version. vCenter also allows you to create alarms and send alerts for specific hardware events to monitor the hardware.
If you are not using vCenter use the Health Status option available in Configuration tab when connected to the ESX host directly using vSphere Client.
With vCenter providing all these options do you really need any other hardware monitoring tool?
I would settle for vCenter since it provides all the options to ensure that the underlying hardware is monitored correctly. To ensure that all the CIM providers for all the hardware is available you may use the OEM versions of ESXi which can be downloaded from the Download VMware vSphere Hypervisor (Based on ESXi) page and check the Optional Binary section. If you don’t find binary for your hardware vendor then you need to contact that vendor.
Apart from vCenter, you may also use the management tools provided by your hardware vendor. I list a couple here but there are many others.
- Dell OpenManage Server Administrator can be used to view the hardware health information, view alerts and configure the hardware and BIOS settings.
- HP SIM 5.3.2 can be used to monitor the hardware information on ESXi, for more information refer to Management of VMware ESXi ™ on HP ProLiant Servers.
With these options available to us, monitoring hardware health really isn’t an issue for those considering the migration to ESXi.