A log-in resource release system includes a set of lists for managing log-in requests to a processing cluster input/output port from host server input/output ports. Host servers that have been granted memory structures within a memory storage device (“configured hosts”) are granted priority access to a storage processing device's input/output port (“cluster port”). If the cluster port has exhausted its log-in resources, log-on requests from non-configured hosts will be not be accepted. New log-in requests from configured hosts will cause a host connected at a link or transport layer but not an upper layer to be logged off. If no hosts are connected only at the link or transport layer, a non-configured host connected at an upper layer will be logged off. If only configured hosts are connected and only at the upper layer, the log-on request by the configured host will be denied.