Communication between vCenter Server and ESX
- vCenter Server interconnects with the ESX/ESXi host agent through the VMware vSphere API (vSphere API).
- When a host is added first to the vCenter Server, vCenter Server sends a vCenter Server agent to run on the host.
- The vCenter Server agent acts as a mini-vCenter Server to make the following functions:
- Relays and enforces source allocation decisions complete in vCenter Server, including those that the DRS engine sends.
- Passes virtual machine provisioning and configuration change commands to the host agent.
- The host agent change the commands of host configuration.
- The host agent performance figures, alarms, and error conditions and sends to the vCenter Server.
- ESX/ESXi hosts allows management at different release versions.