Where soft zoning is preferred over hard zoning
Zoning is an FC switch function that enables nodes within the fabric to be logically segmented into groups that can communicate with each other. The zoning function controls this process by allowing only the members in the same zone to establish these link-level services.
Zoning includes three types:
Port zoning or hard zoning: It uses the FC addresses of the physical ports to define zones. In port zoning, access to data is determined by the physical switch port to which a node is connected. Although this method is secure, it requires updating of zoning configuration information in the event of fabric reconfiguration.
WWN zoning or soft zoning: It uses World Wide Names to define zones. A major advantage of WWN zoning is its flexibility. It allows the SAN to be recabled without reconfiguring the zone information.
Mixed zoning: It combines the qualities of both WWN zoning and port zoning. Using mixed zoning enables a specific port to be tied to the WWN of a node.