A load balancing method and system for identifying an input/output (I/O)
network path from a set off I/O network paths is provided by the
invention. The set off I/O network paths connect a host system via a
network to a storage subsystem. The host system comprises at least one
host bus adapter (HBA) and the storage subsystem comprises at least one
I/O device and the network comprises at least one network device. Each of
the HBA, the I/O device and the network device comprise at least one I/O
port. For each I/O port of each HBA, an HBA port limit is determined.
Additionally the set of I/O network paths which connect the I/O port of
each of the HBA via the I/O ports of the network device to the I/O port
of the I/O device is identified. Then a fabric utilization limit is
determined for each I/O network path and a HBA port utilization is
determined for each I/O port of the at least one HBA. All network paths
are discarded for which the HBA port utilization is greater than the HBA
port limit. For each of the remaining paths a network path distance is
determined. All I/O network paths for which the network path distance is
greater than the path distance limit are discarded. Then for each of the
remaining paths a fabric utilization is determined. All I/O network paths
for which the fabric utilization is greater than the fabric utilization
limit are discarded and the I/O network path is determined from the
remaining network paths.