Fibre Channel Switched Fabric Configuration; Discovery Mode; Host Device Configuration - HP StorageWorks N1200 User Manual

Fibre Channel Switched Fabric Configuration

When connected to a Fibre Channel switch, the router is identified to the switch as
a unique device by the factory programmed World Wide Name (WWN).

Discovery Mode

This feature makes it easy to discover attached Fibre Channel and SCSI target
devices and automatically map them on the host side for the bus/port in question.
There are two discovery methods available:
Auto Discovery can be set to occur after reboot events (when the router reboots)
or link-up events (for instance, when cables are attached or a hub is rebooted).
Auto Discovery can be disabled by setting the router to Manual Discovery.

Host Device Configuration

A host system using a Fibre Channel Host Bus Adapter (HBA) will typically map
devices into the existing device-mapping scheme used by that operating system.
Refer to the HBA manual for the mapping table.
Mapping involves pairing FC_AL_PA to SCSI target address. The HBA will
claim enough SCSI bus entries to allow up to 125 Fibre Channel targets to be
mapped to SCSI Bus: Target entries. This is usually done by a fixed mapping of
AL_PA to Bus: Target. In such a configuration, the router corresponds to a
Bus: Target identifier, with the attached SCSI devices appearing as logical units
(LUNs). Operating systems can extend the available SCSI limit of 15 targets per
bus. Although this is not an issue for the operating system or most applications,
there are cases where older applications can have expectations about what
constitutes a valid SCSI ID, and thus may not correctly handle certain mappings.
In particular, some applications may exhibit difficulties addressing target IDs
greater than 15 (for example, 16 and up). This situation can be resolved by
configuring the router to use hard addressing and setting the AL_PA to a value
less then 16 that the HBA will be able to map.
For example, depending on the Fibre Channel HBA, if the hard AL_PA selection
is 1, then the address is 1. If the selection is 125, the AL_PA address is 0xEF.
Some Fibre Channel HBAs will map devices differently, so verify the AL_PA by
reviewing the documentation for the HBA.
Network Storage Router N1200 User Guide
Manual discovery
Auto discovery
Configuration Overview
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