Patent ID: 7739415

Claim:
A method for managing virtual instances of a physical port attached to a network, where each instance is assigned a Worldwide Port Name (WWPN) and where the network assigns each instance a port identifier, whereby the network provides a separate logical connection for said new port identifier which is logged in with said network and removes said separate logical connection path for said new port identifier when said new port identifier is logged off from the network, the method comprising: assigning the WWPN from a pool of WWPNs and removing said WWPN from said pool of WWPNs; storing the WWPN in a table of WWPNs on a persistent storage device that is not accessed using said network when said new port identifier is logged in said network; deleting said WWPN from said table when said new port identifier is logged off from said network; returning said WWPN to said pool of WWPNs; wherein said WWPN can be marked as either “unlocked” or “locked” in said pool of WWPNs, said pool of WWPNs being marked “locked” are not being used; marking said WWPN as “locked” when said new port identifier is removed; activating a virtual instance for a physical port when said new port identifier was assigned by said network; deactivating said virtual instance, storing the WWPN of said new port identifier together with a unique identifier for said virtual instance in a least-recently-used (LRU) list in the memory when said new port identifier is removed by said network; searching for said unique identifier of said virtual instance in said LRU list when said virtual instance is requested to be activated again; using said WWPN instead of a WWPN from said pool of WWPNs if said unique identifier for said virtual instance is found in said list; verifying that no unintended access rights granting access to certain resources are in place for said WWPN; in response to verifying that no unintended access rights are in place for said WWPN allowing said WWPN to be reassigned to a different sort identifier; defining a set of characteristics; choosing a characteristic from said set of characteristics and assigning the characteristic to said virtual instance; selecting an operating system instance based on said chosen characteristic; and assigning said operating system instance to said virtual instance based on said characteristic.