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VSM monitors vCenter and display information related to the vCenter , this includes ( Total number of managed Virtual machines by vCenter ,ESXi Hosts and Virtual machines).
ESXi Hosts
ESXi is the hypervisor on which you run virtual machines as a set of configuration and disk files that together perform all the functions of a physical machine.
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VSM monitors virtual machines and display information about the VMs (Managing ESXi Host , Data Center, OS ,IP Address and Power status.
VMware Health Summary Dashlet
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