FW V06.XX/HAFM SW V08.02.00 HP StorageWorks SAN High Availability Planning Guide (AA-RS2DD-TE, July 2004)

Planning Considerations for Fibre Channel Topologies
67SAN High Availability Planning Guide
Figure 24: Private device connectivity
Private devices communicate only with other devices on the same arbitrated
loop, and interconnected public and private devices can communicate with
each other. Such intermixed devices establish operating parameters and loop
topology configuration through a port login (PLOGI) command exchange
rather than through the switch’s name server.
Be aware that public device-to-private device communication may cause
problems. For example, it is often critical to separate servers and storage
devices with different operating systems, because accidental transfer of
information from one to another can delete or corrupt data. Plan to implement
security provisions for the switch, such as partitioning attached devices into
restricted-access groups (zoning), providing server-level access control
(persistent binding), or providing storage-level access control. Refer to
“Security Provisions” on page 147 for additional information.
Public Versus Private Loops
Arbitrated loop switches support operation of public and private loops as follows:
■ Public loop — A public loop is connected to a switched fabric (through the
switch B_Port) and the switch has an active embedded FL_Port that is user
transparent. All devices attached to the loop can communicate with each