Load distribution in storage area networks

摘要

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.