Server Manager discovers and monitors VMware Datastore. A datastore is a storage location for virtual machine files, which can be a VMFS volume, a directory on network-attached storage, or a local filesystem path. The monitoring and root-cause analysis of a VMware Datastore connectivity involves monitoring of the Host Bus Adapter (HBA), ScsiLun, and ScsiPath, because a failure on any one of them affects the ESX host to Datastore connectivity.

The monitoring of HBA, ScsiLun, and ScsiPath is based on the extended events from vCenter. ESM polls the vCenter every 4 minutes (default). If there are events that passes the VDC filter, then ESM processes those filtered extended events, which are used for monitoring of HBA, ScsiLun and ScsiPath.


VMware extended event is a dynamically typed class, defined as EventEx.

When a VMware Datastore related extended event is generated, the change is reflected in the updated status of HBA, ScsiLun, and ScsiPath attributes, which are specifically monitored. The values of these attributes are used for root cause analysis of VM, ESX server and VMware cluster related VMware Datastore connectivity failures.

The topology class instances are created in ESM, and their corresponding attributes that are specifically monitored are listed in Datastore topology class and their monitored attribute.

Table 1. Datastore topology class and their monitored attribute

Topology class



It is a physical board that is inserted into a host computer to initiate all communication between the ESX host and the external devices.


It is a logical entity which represents all possible network paths from an ESX host to a file server (FileServer) for Network attached storage (NAS) data transfer in an IP network, or from an ESX host to iSCSI or FCoE based storage.


It is an Small Computer System Interface (SCSI) logical unit. An SCSI logical unit is a host device that an ESX Server or virtual machine can use for I/O operations. An ESX Server creates SCSI logical unit objects to represent devices in the host configuration.


It is a storage entity that represents a topological path from a HBA to Scsi Lun.


It is a redundancy group of SCSI data paths. The Scsi paths are discovered as a redundancy group.