In UML modeling, a node instance is a model element that represents an instantiation, or actual occurrence, of a node.
While a node represents a generic type of computational device, a node instance represents a specific and defined node in your system environment. You can use node instances in deployment diagrams to represent resources that exist at run time. For example, you can use node instances to represent a Web server and a data server in a deployment diagram for an e-commerce application.
Compartments display information about the elements that are deployed on the node instance.
A node instance typically has a unique name that consists of an underlined concatenation of the instance name, a colon (:), and the node name; for example: NodeInstance:Node.
As the following figure illustrates, a node instance is displayed as a three-dimensional rectangle that contains the name of the node instance.
Parent topic: Deployment diagrams
Related tasks
Nesting a node inside another node
Specifying the deployment of an artifact within a node