When you configure application monitoring, ApplicationHA uses heartbeat to communicate the application status to VMware HA. If the application or its component fails, ApplicationHA attempts to restart it. If the application does not start, ApplicationHA stops sending the heartbeat. Depending on the configuration, VMware HA then restarts the virtual machine instantaneously.
A hard restart has various implications and may not be the desired solution at all times. It may prove to be counter productive in several cases, including the following:
The virtual machine itself is running fine but the application is unable to get the required resources
The other applications and tools running on the machine may either hang or take longer time to recover or restart after an abrupt shut down
A hard restart can be potentially disruptive if there are multiple critical applications running on the virtual machine
ApplicationHA provides another layer of application control wherein you can configure ApplicationHA itself to restart the virtual machine using native operating system commands. An operating system driven restart is graceful and allows for a more orderly shut down of applications and tools running on the machine and can help reduce potential disruption to critical applications.
ApplicationHA provides attributes that you can use to configure ApplicationHA to restart the virtual machine.