A single agent manages multiple resources of the same type on one system. For example, the NIC agent manages all NIC resources. The resources to be managed are those defined within the VCS configuration.

As part of the VCS processes, a high availability daemon (HAD) is responsible for making applications highly available on a system.

When the VCS process HAD comes up on a system, it automatically starts the agents required for the types of resources that are to be managed on the system.

The VCS HAD process provides the agents with the specific configuration information for the resources that are configured under VCS.

An agent carries out the commands received from HAD to bring resources online, offline, migrate, and monitor their status, as needed. When an agent crashes or hangs, VCS detects the fault and restarts the agent.