ServerNet Cluster 6780 Operations Guide (G06.28+, H06.05+)

Glossary
ServerNet Cluster 6780 Operations Guide—525606-003
Glossary-23
ServerNet cluster services
ServerNet cluster services. The functions necessary to allow a node to join, participate in,
or leave a ServerNet Cluster. These functions include:
•
Monitoring and control of the physical connections to the cluster
•
Discovery of other nodes in the cluster
•
Establishment of direct connections with the discovered nodes
•
An interface with Expand to provide a high-speed bypass for internode message
transport
•
Monitoring and reporting of the status of connections within the cluster
•
Maintenance and reporting of cluster statistics
•
Automatic recovery of failed connections
•
Shutdown sequencing to allow orderly withdrawal of an individual node from the
cluster
ServerNet cluster subsystem. The subsystem managed by the ServerNet cluster monitor
process (SNETMON). The subsystem name is SCL. The subsystem number is 218.
The subsystem acronym is ZSCL. See also subsystem and ServerNet cluster monitor
process (SNETMON).
ServerNet device. Interface logic that is associated with a specific hardware unit, such as a
processor or I/O adapter, and that provides the interface to the ServerNet
communications network. The responsibilities of the ServerNet device are to transform
message data into ServerNet packets, to transmit those packets, to receive ServerNet
packets, and to unpack the data on behalf of the associated hardware unit.
ServerNet expansion board (SEB). (1) A connector board that plugs in to the backplane to
allow one or more ServerNet cables to exit the rear of the enclosure. The SEBs and
ServerNet cables allow processors in one group to communicate with processors in
another group. Each SEB provides either the ServerNet X fabric or the ServerNet Y
fabric for a group. (2) A collective term for both SEBs and modular SEBs (MSEBs)
when a distinction between the two types of SEBs is not required.
ServerNet ID. A unique identifier for an addressable unit on a ServerNet communications
network. A unit can have multiple ServerNet node IDs. This ID is used for routing: each
packet has a source ServerNet node ID and a destination ServerNet node ID. A pair of
processors operating in duplex mode share one ServerNet node ID.
ServerNet/FX adapter. A ServerNet adapter that logically extends the ServerNet X and Y
fabrics to other clusters in a Fiber Optic Extension (FOX) ring by using fiber-optic lines.
Two ServerNet/FX adapters are used, one for the X ring and one for the Y ring.
ServerNet link. Two unidirectional point-to-point communication paths, one in each
direction, connecting a router to a ServerNet node or another router. Each ServerNet
link contains a transmit channel and a receive channel.