The IBTopo package contains a set of perl modules and a script
that uses the modules to process network connectivity information.

The perl modules parse output from ibnetdiscover and present
abstractions for different network topologies.  In particular, there
are three interfaces:

ibnetdiscover
Interface to read ibnetdiscover output.

ibnetupdown
Interface to read network info assuming an up/down network, meaning
all HCAs and switches can be classified as belonging to a certain
level, with all HCAs at the level 0, all leaf switches at level 1,
and other switches at higher levels.  Such a network has the property
that for an object at a level i, each link is either a down link which
connects to an object at level i-1 or each link is an up link which
connects to an object at level i+1.

ibnetfattree
Interface assuming a particular type of up/down network in which
all objects at a given level can be grouped, so that one can send a
packet from any object in the group and reach any other object in the
group with the same number of network hops.

The topo script uses the ibnetfattree module to process ibnetdiscover
output and produce HCA grouping information.  It assigns IDs to each
HCA for each level in the network, which consicely describes the number
of hops between any pair of HCAs in the system.  See the topo/README
file for more info.