A fabric having switches interconnected with multiple parallel interswitch links can be configured using staged port bring up. Only one of the multiple parallel interswitch links between any two switches and the corresponding switch ports can be selected and initialized. The fabric can be configured with the selected ISLs. Once the fabric has stabilized, unselected ISLs and the corresponding switch ports can be incrementally initialized. The number of unselected ISLs to be initialized can be determined based on the available computing resources of the fabric switches.