VCS also starts HostMonitor daemon when the VCS engine comes up. The VCS engine creates a VCS resource VCShm of type HostMonitor and a VCShmg service group. The VCS engine does not add these objects to the main.cf file. Do not modify or delete these VCS components. VCS uses the HostMonitor daemon to monitor the resource utilization of CPU, Memory, and Swap. VCS reports to the engine log if the resources cross the threshold limits that are defined for the resources. The HostMonitor daemon also monitors the available capacity of CPU, memory, and Swap in absolute terms, enabling the VCS engine to make dynamic decisions about failing over an application to the biggest available or best suitable system.
VCS deletes user-defined VCS objects that use the HostMonitor object names. If you had defined the following objects in the main.cf file using the reserved words for the HostMonitor daemon, then VCS deletes these objects when the VCS engine starts:
Any group that you defined as VCShmg along with all its resources.
Any resource type that you defined as HostMonitor along with all the resources of such resource type.
Any resource that you defined as VCShm.
You can control the behavior of the HostMonitor daemon using the Statistics attribute.
See Cluster attributes.