A method is provided with which a name of a virtual port is not changed when virtualized storage is moved among switches. Information about a creator and a borrower of name information is added to a table including name information and address information of a virtual port of a name server managing the name information and the address information. The name information is provided to plural switches and managed. In addition, name information, which can be used commonly among name servers managing the name information and the address information is pooled in advance, and the name information of the virtual port is borrowed from there.