Abstract: Methods, systems, switches, and products are provided for global first, non-minimal routing in a Dragonfly topology. Embodiments include receiving, on a terminal link of a switch, a packet whose destination is in another VRG and routing, by the switch, the packet to a switch in another VRG on a global link.

Abstract: Methods and systems for dynamic port subdivision during link negotiation and initiation are provided. Embodiments include selecting a reference lane from port configuration information for the potential link partner; selecting a subdivision evaluation lane from the port configuration information for of the potential link partner; and comparing a GUID and port number of the reference lane with a GUID and port number of a subdivision evaluation lane. If the GUID and port number of a reference lane and the GUID and port number of a subdivision evaluation lane are not the same, embodiments include subdividing the port into a plurality of subdivided ports.

Abstract: Creating a high-performance computing environment including a plurality of switches and a plurality of cables connecting the switches in a cyclic topology is provided. Embodiments include determining the number of virtual routing groups (‘VRGs’) for the cyclic topology, assigning each VRG a unique VRG identifier (‘VRG ID’); assigning to each VRG a plurality of switches; establishing, through at least one switch in each VRG, a cyclic connection with every other VRG in the topology wherein a cyclic connection is formed by connecting one switch from each VRG in a cyclic set of VRGs to the same switch in every other VRG in the cyclic set and wherein the VRGs are connected to one another according to a set of square matrices of VRGs.

Abstract: Routing in a multi-computer network comprising a plurality of multi-switch virtual router groups (‘VRGs’) interconnected by only cyclic connections among the VRGs is provided. A cyclic connection is formed by connecting one switch from each VRG in a cyclic set of VRGs to the same switch in every other VRG in the cyclic set and each switch in the cyclic set is connected in an all-to-all configuration. Every VRG in the network has at least one cyclic connection with every other VRG in the network. Embodiments include selecting a non-minimal path between a source VRG and a destination VRG in a cyclic set that passes through only one switch in a pass-through VRG in the cyclic set; and sending packets from the source VRG in the cyclic set to the destination VRG through the one switch in the pass-through VRG.

Abstract: Efficient, reliable broadcast support is provided to clients of a network built using switching elements that have the capability to replicate packets. Replication patterns are generated and used in broadcasting data in the network. The replication patterns are provided in hardware of the network to enable broadcasting from one node in the network to each node of a broadcast domain of the network.

Abstract: Deadlocks are avoided in performing failovers in communications environments that include partnered interfaces. An ordered set of steps are performed to failover from one interface of a partnered interface to another interface of the partnered interface such that deadlocks are avoided.

Abstract: In a communications network having a plurality of interconnected nodes adapted to communicate with each other by transmitting packets over links, with more than one path available between source-destination node pairs, a network interface is associated with each node. Each network interface has a plurality of route tables for defining a plurality of routes for transferring packets from the associated node as source node to a destination node. Each network interface further includes a path status table of path status indicators, e.g., bits, for indicating whether each route in the route table is usable or unusable as being associated with a fault. A network manager monitors the network to identify link events, and provides path status indicators to the respective network interfaces. The network manager determines the path status indicator updates with reference to a link level of each link event, and consolidates multiple substantially simultaneous link events.

Abstract: In a communications network having a plurality of nodes adapted to communicate with each other, and more than one path available between most source-destination node-pairs, a network interface is associated with each node. Each network interface has a plurality of route tables for defining a plurality of routes for transferring each packet from a source node to a destination node. Each network interface further includes a path status table of path status indicators, e.g., bits, for indicating whether each route in the route tables is usable or is unusable as being associated with a fault. The network manager monitors the network to identify faults and provides the path status indicators to the respective network interfaces. Failed routes in the network are avoided based on the path status indicators. When a failed route is restored, such that the route is usable again, the path status table indicates that the usable state is restored.

Abstract: Endpoint identifiers are dynamically assigned to network interfaces, in response to a change in physical connection. When a physical connection associated with a network interface is changed, such as a cable coupling the network interface to an endpoint is moved from one location to another location, a new endpoint identifier is assigned to the network interface. The new endpoint identifier is based on the location of the new endpoint.

Abstract: A distributed divide and conquer route generation technique is provided for facilitating routing of data packets in a network of interconnected nodes. The network includes differently sized building block types, with each building block type including at least one node of the network and at least one switch chip of the network, wherein differently sized building block types include different numbers of switch chips of the network. The technique includes identifying building block types to which a source node of the network belongs, and for each building block type: selecting a destination chip within the building block type that does not belong to a smaller building block type; selecting at least one route to at least one destination node of the destination chip based on a fanning condition; and repeating the two selecting steps for each destination chip within the building block type.

Abstract: A fanning route generation technique is provided for multi-path networks having a shared communications fabric. The technique includes selecting a source node-destination node (S-D) group having common starting and ending sets of links from the network of interconnected nodes. Within this group, selecting the shortest routes between the S-D nodes of the group so that: selected routes substantially uniformly fan out from the source node to a center of the network and fan in from the center of the network to the destination node, thereby achieving local balance; and global balance of routes passing through links that are at a same level of the network is achieved.

Abstract: An exemplary method of identifying configuration topology, existing switches, and miswires in a given network is provided. Given a number of switches, which may be less than the maximum possible for the actual configuration and some ports of which may be miswired, generate a hypothesis for the supported topology of which the existing configuration is a subset. Perform a best fit of the existing switches to the supported number switches of the maximal topology, using formulae for the connections of the maximal supported topology. If supported switches are found missing in the assumed topology, increase the switch count accordingly, and start over with a new hypothesis. When satisfied with identification, revisit all switch ports and use the connection formulae to identify all miswires.