Zoning - HP A7340A - Surestore FC 1Gb/2Gb Switch 16B User Manual

Zoning

Zoning is essentially a filter that is applied by the nameserver against the query
from the initiator which limits the information returned by the nameserver to the
initiator. A zone contains the WWN of the initiator and the WWN of any devices
that it is allowed to access. When an initiator queries the nameserver for
accessible devices in the fabric, the nameserver will look for all zones that contain
the WWN of the initiator. Then a list is formed from all the members of the zones
and is applied to the contents of the nameserver. Only devices that are in the list
and in the nameserver are returned to the initiator as accessible devices. The
initiator then uses the list of returned devices, along with the access parameters
returned and proceeds to further inquire of the devices for specific operational
capabilities.
Devices that are not part of the zone are not returned as accessible devices. It is
important to note that this process does not prohibit access to the device. If the
initiator has prior knowledge of the device, it can access the device. The
nameserver does not control access to devices on the fabric. Dependable zoning
operation depends on the cooperation of all devices in the fabric to only access
devices that are returned in the query from the nameserver. HP fabric switches
provide for hardware enforcement of the zoning configuration to prevent
unwanted access to devices.
Devices can be listed in more than one zone. Thus, overlapping zones are
permitted. A concept of most permissible access is used in zoning. When an
initiator requests the list of accessible devices, if at least one zone containing the
WWN of the initiator exists then any device in that zone is accessible. If the same
device exists in another zone that does not contain the WWN of the initiator, the
device is still accessible to the initiator.
Zoning Version 3.1.x/4.1.x User Guide
Zoning Concepts and Guidelines
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