VMware High Availability (HA) provides automatic detection of hardware failures, server failures, and operating system failures. In the event of a physical server failure, VMware HA automatically restarts the affected virtual machine on other production servers that have spare capacity. In the event of an operating system failure, VMware HA restarts the affected virtual machine on the same server.
VMware HA ensures that capacity is available to restart all virtual machines that are affected by a service failure. HA continuously monitors capacity utilization and reserves spare capacity to restart virtual machines.
VMware HA helps users identify abnormal configuration settings detected within HA clusters. The VMware vSphere client interface reports relevant operating status and potential error conditions along with suggested remediation steps.
For more information, see the VMware website at https://www.vmware.com/pdf/ha_datasheet.pdf.
Note:
All virtual machines and their configuration files must be on shared storage, e.g. Fibre Channel SAN, iSCSI SAN, or SAN iSCI NAS.
The console network must have redundant network paths to have reliable failure detection for HA clusters. VMware HA monitors the heartbeat between hosts on the console network for failure detection.
VMware HA uses virtual machine priority to decide order of restart.
VMware HA only works across a LAN. VMware HA does not work across a WAN.
