What is VMware High Availability (HA)?
by VCP Help on 19/01/09 at 8:10 pm
VMware HA is a technology that helps with maintaining maximum uptime in a production environment by monitoring server status and automatically restarting servers on other hosts if necessary. By using a combination of techniques, the HA process will identify when a VM has become unreachable for any number of reasons and when this happens, the HA agent will power the VM up on another ESX host.
The HA process can determine that a VM is unreachable in a number of ways such as by network connectivity, heartbeat, or even by failure of an application. These conditions can trigger failover and thus the starting of another instance of the VM in question so that visible downtime to users is minimized.
VMware High Availability requires Virtual Center to setup and configure, but once it is configured, the VC machine can be removed (for example if it crashes) and the ESX hosts will continue to operate the HA environment.
