Computer identity

In Snow Integration Manager, a computer is identified by its hostname and site name. These two properties combine to define the unique identity of a computer that is inventoried via Snow Integration Manager.

Identity management is subsequently handled by Snow Inventory, which decides whether data it receives is for a new or existing computer.

If the hostname or site name for a computer that is inventoried via Snow Integration Manager changes between data scans, Snow Inventory identifies the computer as new, unless an existing computer with those parameters already exists.

Snow Integration Manager connectors retrieve not only pure inventory data but also a time stamp for when the data was updated. This time stamp is created by the data sources from where the connectors retrieve data, except for connectors where such a time stamp does not exist. These connectors are:

  • Citrix XenServer

  • Microsoft Hyper-V/SCVMM

  • VMware vSphere

  • Red Hat Enterprise Virtualization

For these four connectors, the time stamp for when data was aggregated by Snow Integration Manager will be used.

When Snow Inventory receives computer inventory data via Snow Integration Manager, it first determines if the data is for a new or existing computer. If the data is for a computer that does not exist in Snow Inventory, a new computer object is created, and its data is saved. If the data is for a computer that already exists in Snow Inventory, the data time stamp of the received data is compared with the time stamp that exists in Snow Inventory.

If the time stamp of the received data is subsequent to the time stamp that exists in Snow Inventory, the data is appended. If the time stamp of the received data is antecedent to the time stamp that exists in Snow Inventory, the data is discarded.

In other words, if data that is received is time stamped as having been produced at a date and time after the data that already exists in Snow Inventory, it is appended. Otherwise, it is discarded.

There is one exception to how Snow Inventory decides what inventory data to save and what to discard, which can be enabled by configuring the module named DiscardOldSnapshotData in the Snow Inventory configuration file to false:

<Module typeName="SnowSoftware.Inventory.DataProcessor.FileProcessorModule">
    <Setter propertyName="DiscardOldSnapshotData">false</Setter>
</Module>

Configuring the DiscardOldSnapshotData module in Snow Inventory to false allows Snow Inventory to append all received data as it is received, and disregard the default process of considering the time stamp for when data was updated.

In other words, if the DiscardOldSnapshotData module is configured to false, Snow Inventory appends all data, regardless of whether the received data is older or newer than what already exists.