Hostd, vpxa and the vSphere API/SDK – Confusion on where the APIs actually live

Hi All,

I’m taking the VMware vSphere Deploy, Manage course and was confused about this:

  • In one slide, the instructor showed that vCenter Server communicated with the ESXi host using vSphere APi/SDK (The VMware Host Client also communicated using this)
  • In another slide, the instructor showed that the vCenter Server communicated with a vCenter agent living on the ESXi host (vpxa). This then communicated with another process called hostd, which then executed commands at the hypervisor…

With the second bullet point in mind, where does the vSphere API/SDK fit in? Is hostd the item that houses the vSphere API? Does vCenter communicate with vpxa, which then communicates with hostd using the vSphere API/SDK?


Clarification would be much appreciated.