Understanding Node Groups

Network Node Groups

A set of one or more Node devices that connect to an external network is called a network Node group. When configured, the Node devices within a network Node group work together in tandem as a single entity. The network Node group also relies on an external Routing Engine running on the Director group. This network Node group Routing Engine runs the routing protocols required to support the connections from the network Node group to external networks. By default, Node devices do not connect to external networks, but instead connect to endpoints such as servers and storage devices. As a result, you must configure a network Node group explicitly in the default partition of the QFabric switch so that this entity may launch the network Node group Routing Engine and connect to external networks.

In a QFabric switch deployment that requires connectivity to external networks, you can modify the automatically generated network Node group by including its preset name NW-NG-0 in the configuration. Within a network Node group, you can include a minimum of one Node device up to a maximum of eight Node devices. By adding more Node devices to the group, you provide enhanced scalability and redundancy for your network Node group.

Note: The QFabric switch creates a single NW-NG-0 network Node group for the default partition. You cannot configure a second network Node group inside the default partition. The remaining Node devices within the default partition are reserved to connect to servers, storage, or other endpoints internal to the QFabric switch. These Node devices either can be retained in the automatically generated server Node groups or can be configured as part of a redundant server Node group.

Server Node Groups

A server Node group is a set of one or more Node devices that connect to servers or storage devices. Unlike Node devices that are part of a network Node group and rely on an external Routing Engine, a Node device within a server Node group connects directly to endpoints and implements the Routing Engine functions locally, using the local CPU built into the Node device itself.

By default, each Node device is placed in its own self-named autogenerated server Node group to connect to servers and storage. You can override the default assignment by manually configuring a redundant server Node group that contains a maximum of two Node devices. You can use a redundant server Node group to provide multihoming services to servers and storage, as well as configure aggregated LAG connections that span the two Node devices.