FW 05.01.00 and SW 07.01.00 HP StorageWorks SAN High Availability Planning Guide (AA-RS2DC-TE, June 2003)

Planning Considerations for Fibre Channel Topologies
109SAN High Availability Planning Guide
In addition to OEM limitations not discussed in this publication, the
considerations that need to be evaluated when intermixing FCP and FICON
protocols are:
■ Director or switch management.
■ Port numbering versus port addressing.
■ Management limitations.
Director or Switch Management
When intermixing FCP and FICON protocols, it must be determined if the
director or switch is to be managed through Open Systems management style or
FICON management style. This setting only affects the management style used to
manage the director or switch; it does not affect Fibre Channel port operation.
FCP devices can communicate with each other when the attached fabric element
is set to FICON management style, and FICON devices can communicate with
each other when the attached fabric element is set to Open Systems management
style.
When a director or switch is set to Open Systems management style, FCP
connectivity is defined within a Fibre Channel fabric using WWNs of devices that
are allowed to form connections. When connecting to the fabric, an FCP device
queries the name server for a list of devices for which connectivity is allowed.
This connectivity is hardware enforced through a name server zoning feature that
partitions attached devices into restricted-access zones.
When a director or switch is set to FICON management style, host-to-storage
FICON connectivity and channel paths are defined by a host-based hardware
configuration definition (HCD) program. Additional connectivity control is
managed at the director or switch level by configuring the logical port addresses
that are allowed to, or prohibited from, connecting with each other. FICON
devices do not query the name server for accessible devices because connectivity
is defined at the host. This connectivity is hardware enforced in the routing tables
of each port.