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If one of the hosts in the cluster fails, the vSphere HA feature restarts a VM on another host that has enough free resources. Dell Technologies strongly recommends that you enable this feature in a vSphere cluster with SAP HANA. The SAP HANA service autostart feature must be enabled in the SAP HANA software.
Enable the autostart feature at the time of SAP HANA installation or by setting the autostart option to 1 in the /hana/shared/<SID>/profile/<SID>_HDB<InstNo>_<hostname> file. The minimum vSphere HA settings must be in place, as shown in the following figure:
The SAP HANA service auto restart watchdog function monitors the SAP HANA application and the associated services in a VM. The auto restart function automatically detects a failure and restarts the corresponding SAP HANA process: nameserver, index server, and so on.
The vSphere HA VM heartbeat monitoring feature restarts the guest operating system of the VM and SAP HANA on the same host. The monitoring feature also handles operating system failures when the SAP HANA automatic restart options are enabled.
Enable the heartbeat monitoring feature after vSphere HA is enabled. Set VM monitoring sensitivity to High, as shown in the following figure:
Enabling heartbeat monitoring requires that VMware Tools are installed and running in the VM. To install VMware Tools as part of the operating system, use open-vm-tools or use vSphere Web Client and select Guest OS > Install VMware Tools in the VM context menu.
Note: For more information about VMware HA and virtualized SAP HANA HA best practices, see the “vSphere Clustering Service” section in the VMware vSphere best practices and reference architecture guide for SAP HANA.