Addressing, structures and operation – Dell PowerVault 35F (Fibre Channel Bridge) User Manual

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SCC Structures and Operation: Dell PowerVault 35F User's Guide

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Addressing, Structures and Operation: Dell PowerVault 35F User's Guide

SCC Addressing Option

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Auto Assigned Addressing Option

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Index Addressing Option

Fibre Channel and SCSI systems employ different methods of addressing devices. The inclusion of a bridge or bridge
requires that a method of translating device IDs be implemented so that each SCSI device is mapped to the appropriate
Fibre Channel LUN. The SCSI buses establish bus connections between devices. Targets on a SCSI bus may internally
address logical units. The addressing of a specific SCSI device is represented by the BUS:TARGET:LUN triplet.

When a Fibre Channel initiator initializes on an arbitrated loop, the first order of business is to determine what devices
exist on the loop. Device discovery is performed, and an FCP target device list is built. Each device is queried for FCP
logical units. The logical units are the actual devices that the operating system will address. When an initiator
addresses a logical unit, the LUN field used is consistent in form with the SCC defined fields. All current Fibre
Channel host bus adapter drivers are consistent with these methods. The addressing used is the SCC Logical Unit
Addressing and Peripheral Device Addressing methods, shown in

Table 1

and

2

. First level addressing is supported, so

only the first 2 bytes of the 8 byte FCP LUN are used.

Table 1. SCC Addressing structure

Table 2. Peripheral Device Addressing LUN structure

Table 3. SCC Logical Unit Addressing LUN structure

Table 4. Address Method definitions

Codes

Description

00

Peripheral Device Addressing Method

01

Volume Set Addressing Method

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