Hi Hari,
"management" agents/services on ESXi are located under /etc/init.d they are installed with host software:
hostd, ntpd, sfcbd, slpd, wsman, vobd
Agents which comes exclusively from vCenter Server are:
vCenter agent:
"vpxa" - the software that collects, communicates, and executes the actions received from vCenter Server. The vCenter Server agent is installed the first time any host is added to the vCenter Server inventory
Status check: /etc/init.d/vpxa status
HA agent:
"vmware-fdm" (FDM/Fault Domain Manager)
On older pre 5.0 hosts its AAM agent
Regards,
P.