Brocade Communications Systems A7533A - Brocade 4Gb SAN Switch Base Service manual

53-1000603-01
19 October 2007
iSCSI Gateway Service
Administrator’s Guide
Supporting Fabric OS v6.0.0

Copyright © 2007 Brocade Communications Systems, Inc. All Rights Reserved.
Brocade, the Brocade B weave logo, Fabric OS, File Lifecycle Manager, MyView, Secure Fabric OS, SilkWorm, and StorageX are
registered trademarks and the Brocade B wing logo and Tapestry are trademarks of Brocade Communications Systems, Inc., in
the United States and/or in other countries. FICON is a registered trademark of IBM Corporation in the U.S. and other countries.
All other brands, products, or service names are or may be trademarks or service marks of, and are used to identify, products or
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Notice: This document is for informational purposes only and does not set forth any warranty, expressed or implied, concerning
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this document at any time, without notice, and assumes no responsibility for its use. This informational document describes
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www.brocade.com/support/oscd.
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Document History
The following table lists all versions of the iSCSI Gateway Service Administrator’s Guide.
Corporate Headquarters
Brocade Communications Systems, Inc.
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Email: [e-mail]
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Document Title Publication
Number Summary of Changes Publication Date
iSCSI Gateway Service
Administrator’s Guide
53-1000412-01 First version October 2006
iSCSI Gateway Service
Administrator’s Guide
53-1000440-01 Second version June 2007
iSCSI Gateway Service
Administrator’s Guide
53-1000603-01 Third version October 2007

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Contents
About This Document
Supported hardware and software . . . . . . . . . . . . . . . . . . . . . . . . . . vii
How this document is organized . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
Document conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Text formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Notes, cautions, and warnings . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Key terms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Additional information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Brocade resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Other industry resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii
Optional Brocade features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii
Getting technical help. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii
Document feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Chapter 1 Introduction to the iSCSI Gateway Service
In this chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Supported iSCSI initiators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Overview of iSCSI gateway service. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
How iSCSI sessions are translated . . . . . . . . . . . . . . . . . . . . . . . . 3
Presenting FC targets as iSCSI virtual targets . . . . . . . . . . . . . . . 4
Identifying iSCSI components . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Controlling access to the iSCSI VT . . . . . . . . . . . . . . . . . . . . . . . . 6
Switch-to-iSCSI initiator authentication . . . . . . . . . . . . . . . . . . . . 7
Load balancing through connection redirection . . . . . . . . . . . . . 7
Checklist for configuring iSCSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Chapter 2 Configuring the FC4-16IP Blade
In this chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
FC4-16IP port numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Enabling the iSCSI gateway service . . . . . . . . . . . . . . . . . . . . . . . . . .13
Enabling the GbE interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

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Configuring the GbE interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Assigning an IP address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Adding static IP routes (optional) . . . . . . . . . . . . . . . . . . . . . . . . 16
Verifying the network connection . . . . . . . . . . . . . . . . . . . . . . . . 16
Adding ARP entries (optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Chapter 3 Configuring iSCSI Virtual Targets
In this chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Changing and displaying the IQN Prefix. . . . . . . . . . . . . . . . . . . . . . . 19
Mapping FC targets to iSCSI VTs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Automatically creating iSCSI Virtual targets. . . . . . . . . . . . . . . .20
Creating iSCSI VTs manually . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Displaying the iSCSI VT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Displaying LUN map configurations . . . . . . . . . . . . . . . . . . . . . . 27
Displaying iSCSI VT state and status . . . . . . . . . . . . . . . . . . . . . 28
Configuring discovery domains . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Showing iSCSI initiator IQNs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Creating discovery domains . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Configuring discovery domain sets . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Creating a DDSet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Enabling a DDSet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Configuring iSCSI initiator-to-VT authentication . . . . . . . . . . . . . . . . 31
Setting the user name and shared secret . . . . . . . . . . . . . . . . . 31
Configuring iSCSI VT authentication. . . . . . . . . . . . . . . . . . . . . . 31
Binding user names to an iSCSI VT . . . . . . . . . . . . . . . . . . . . . . 32
Deleting user names from an iSCSI VT binding list . . . . . . . . . . 32
Displaying CHAP configurations . . . . . . . . . . . . . . . . . . . . . . . . . 33
Committing the iSCSI-related configuration . . . . . . . . . . . . . . . . . . .33
Displaying current transactions . . . . . . . . . . . . . . . . . . . . . . . . .33
Saving current transactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Resolving conflicts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Enabling/disabling connection redirection for load balancing . . . .35
LUN masking considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Chapter 4 Creating the iSCSI FC Zone
In this chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Overview of iSCSI FC zoning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

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Creating an iSCSI FC zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Creating a zoning configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Chapter 5 Administering the iSNS Client
In this chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Overview of iSNS configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Displaying iSNS service status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Enabling the iSNS client service . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Disabling the iSNS client service . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Clearing the iSNS client configuration. . . . . . . . . . . . . . . . . . . . . . . . 48
Appendix A Scalability Guidelines
Appendix B Troubleshooting
Index

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About This Document
This document is a procedural guide to help SAN administrators configure and manage the iSCSI
gateway service on the FC4-16IP blade in a Brocade 48000 director.
Supported hardware and software
This document is specific to Fabric OS v6.0.0 or higher running on the Brocade 48000 director with
an FC4-16IP blade installed.
In those instances in which procedures or parts of procedures documented here apply to some
switches but not to others, this guide identifies which switches are supported and which are not.
This document sometimes mentions other Fabric OS releases to highlight the changes in the latest
release or to point out interoperability issues with other Brocade models. It also specifies when
procedures or steps of procedures apply only to specific Brocade models.
Although many different software and hardware configurations are tested and supported by
Brocade Communications Systems, Inc. for this Brocade Fabric OS release, documenting all
possible configurations and scenarios is beyond the scope of this document.
How this document is organized
The document contains the following topics:
•Chapter 1, “Introduction to the iSCSI Gateway Service” describes the iSCSI gateway service
supported on the Brocade 48000 director running Fabric OS v6.0.0 or higher with one or more
iSCSI-enabled FC4-16IP blades.
•Chapter 2, “Configuring the FC4-16IP Blade” provides the initial setup steps to deploy an iSCSI
gateway solution.
•Chapter 3, “Configuring iSCSI Virtual Targets” describes how to create iSCSI virtual targets,
discovery domains, discovery domain sets, and how to configure iSCSI VT-iSCSI initiator
authentication.
•Chapter 4, “Creating the iSCSI FC Zone” describes how to create an iSCSI zone for discovery
domains.
•Chapter 5, “Administering the iSNS Client” describes how to enable the iSNS client on an iSCSI
gateway and configure it with an iSNS server.
The appendices provide scalability guidelines and troubleshooting assistance.

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Document conventions
This section describes text formatting conventions and important notices formats.
Text formatting
The narrative-text formatting conventions that are used in this document are as follows:
bold text Identifies command names
Identifies the names of user-manipulated GUI elements
Identifies keywords and operands
Identifies text to enter at the GUI or CLI
italic text Provides emphasis
Identifies variables
Identifies paths and Internet addresses
Identifies document titles
code text Identifies CLI output
Identifies syntax examples
For readability, command names in the narrative portions of this guide are presented in mixed
lettercase: for example, switchShow. In actual examples, command lettercase is often all
lowercase. Otherwise, this manual specifically notes those cases in which a command is case
sensitive. The ficonCupSet and ficonCupShow commands are an exception to this convention.
Notes, cautions, and warnings
The following notices appear in this document.
NOTE
A note provides a tip, emphasizes important information, or provides a reference to related
information.
A caution alerts you to potential damage to hardware, firmware, software, or data.
A warning alerts you to potential danger to personnel.

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Key terms
For definitions of SAN-specific terms, visit the Storage Networking Industry Association online
dictionary at: http://www.snia.org/education/dictionary.
For definitions specific to Brocade and Fibre Channel, see the Brocade Glossary.
The following terms are used in this manual to describe the iSCSI gateway service and its
components.
discovery domain
(DD) A group of iSCSI virtual targets and iSCSI initiators. Discovery domains
are used for access control and authentication. Only the iSCSI initiators in the
same discovery domain as the iSCSI virtual targets can connect to the FC
targets. When there are no discovery domains, all iSCSI initiators can access
all iSCSI virtual targets (and therefore all FC targets) on the gateway.
discovery domain set
(DDSet) A group of discovery domains that can be enabled or disabled. The
set is used to configure access control and authentication models.
FC portal
An FC_Port that connects the iSCSI virtual initiator to the SAN.
iSCSI virtual initiator
(iSCSI VI) Proxies iSCSI initiator connections to iSCSI virtual target with the
physical FC targets on the SAN. Each iSCSI-enable port has one iSCSI virtual
initiator. An iSCSI virtual initiator is similar to an F_Port in the fabric. The iSCSI
VI registers with the Name Server using a symbolic port name (PWWN) and
node name (NWWN).
IQN
(iSCSI Qualified Name) An iSCSI address that uniquely identifies an iSCSI
device on the network. It is the equivalent of a Fibre Channel WWN and is in
human readable form. The iSCSI gateway supports only IQNs and does not
support IEEE, EUI, and IEEE NAA names.
iSCSI initiator
In client/server terminology, a client that connects to a service (iSCSI virtual
target) offered by the server (iSCSI gateway). It is identified by an IQN. The
iSCSI initiator proxies communications between applications and data
located on a remote SCSI devices to allow applications to access data from a
remote SCSI device, such as an FC target across a TCP/IP network.
iSCSI portal
An iSCSI-enabled FC4-16IP GbE port that is assigned an IP address and
connected to the (IP) network. This port receives the iSCSI initiator
connection to the iSCSI virtual target. The port is bound to an iSCSI virtual
initiator that connects to the FC target in the SAN.

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iSCSI portal group
A set of iSCSI-enabled ports. The portal group allows the iSCSI initiator to
access iSCSI virtual targets using any available port. An iSCSI session may
have several connections to an iSCSI VT on any port in the group. Each
FC4-16IP blade has eight GbE ports. The portal group name is the slot
number of the blade. All online iSCSI-enabled GbE ports participate in the
portal group.
iSCSI virtual target
(iSCSI VT) An iSCSI representation of LUNs from one or more FC targets. The
physical FC LUN is mapped to the iSCSI virtual targets. It is identified by an
IQN. The iSCSI gateway proxies the iSCSI initiators connection to the physical
FC targets using iSCSI virtual targets.
iSCSI connection
A single link between an iSCSI initiator and iSCSI target over a TCP/IP network
that carries control messages, SCSI commands, parameters, and data.
iSCSI session
The basic communication “pipe” from an iSCSI initiator to an iSCSI virtual
target. A session is a group of TCP/IP connections that link an iSCSI initiator
with an iSCSI virtual target. Connections can be added or removed from a
session. Sessions are identified by a Session ID (SSID).
iSNS client
Initiates transactions with iSNS servers using the iSNSP, registers device
attribute information in a common discovery domain, downloads information
about other registered clients and receives asynchronous notification of
events that occur in their discovery domains.
iSNS server
Responds to iSNS protocol queries and requests made by iSNS clients using
the iSNSP. iSNS servers initiate iSNSP state change notifications and store
properly authenticated information submitted by a registration request in an
iSNS database.
iSNS database
Both iSCSI initiators and targets can register, and each entity can inquire
about other initiators and targets. For example, a client initiator can obtain
information about target devices from an iSNS server.
LUN mapping
Logic Unit Number mapping. The mapping of the iSCSI virtual target and the
physical FC target.

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Additional information
This section lists additional Brocade and industry-specific documentation that you might find
helpful.
Brocade resources
The most recent version of documentation is provided on the Brocade Web site, through Brocade
Connect.
NOTE
Go to http://www.brocade.com and click Brocade Connect to register at no cost for a user ID and
password.
The following documentation is available for Fabric OS:
•Fabric OS Administrator’s Guide
•Fabric OS Command Reference
•Advanced Web Tools Administrator’s Guide
•Fabric OS MIB Reference
•Fabric OS Message Reference
•Brocade Glossary
The following documentation is available for Brocade 48000 director and iSCSI blade:
•Brocade 48000 Hardware Reference Manual
•Brocade 48000 QuickStart Guide
•FC4-16IP Hardware Reference Manual
For practical discussions about SAN design, implementation, and maintenance, you can obtain
Building SANs with Brocade Fabric Switches through:
http://www.amazon.com
For information about how to use Fabric OS features in a SAN solution, refer to the Principles of
SAN Design (ISBN 0-7414-2824-5), available from the SAN Administrator’s Bookshelf. You can
order the book and view a sneak preview at:
http://www.brocade.com/products/sanadmin_bookshelf/index.jsp
For additional Brocade documentation, visit the Brocade SAN Info Center and click the Resource
Library location:
http://www.brocade.com
Release Notes are available on the Brocade Connect Web site and are also bundled with the Fabric
OS firmware.

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Other industry resources
For additional resource information, visit the Technical Committee T11 Web site. This Web site
provides interface standards for high-performance and mass storage applications for Fibre
Channel, storage management, as well as other applications:
http://www.t11.org
For information about the Fibre Channel industry, visit the Fibre Channel Industry Association Web
site:
http://www.fibrechannel.org
For information about the iSCSI (internet small computer systems interface) standards, visit the
following Web site:
http://www.ietf.org/rfc/rfc3720.txt
Optional Brocade features
For a list of optional Brocade features and descriptions, see the Fabric OS Administrator’s Guide.
Getting technical help
Contact your switch support supplier for hardware, firmware, and software support, including
product repairs and part ordering. To expedite your call, have the following information available:
1. General Information
•Technical Support contract number, if applicable
•Switch model
•Switch operating system version
•Error numbers and messages received
•supportSave command output
•Detailed description of the problem and specific questions
•Description of any troubleshooting steps already performed and results
•Serial console and telnet session logs
•syslog message logs
2. Switch Serial Number
The switch serial number and corresponding bar code are provided on the serial number label,
as illustrated below.
*FT00X0054E9*
FT00X0054E9
The serial number label is located as follows:
•Brocade 3014—On the top of the chassis, under the insertion arm
•Brocade 3016 and 4012—On the bottom of the switch module
•Brocade 200E, 3200, 3250 and 3850—On the bottom of the chassis

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•Brocade 3800 and 3900— Nonport side of the chassis
•Brocade 4100, 4900, 5000 7500, and 7600—On the switch ID pull-out tab located inside
the chassis on the port side on the left
•Brocade 12000, 24000, and 48000—Inside the chassis next to the power supply bays
•Brocade Multiprotocol Router Model AP7420—On the bottom of the chassis and on the
back of the chassis.
3. World Wide Name (WWN)
•Brocade 200E, 3014, 3016, 3250, 3800, 3850, 3900, 4012, 4100, 4900,5000,
7500and 7600 switches and Brocade 24000, and 48000 directors: Provide the license
ID. Use the licenseIdShow command to display the license ID.
•Brocade Multiprotocol Router Model AP7420: Provide the switch WWN. Use the
switchShow command to display the switch WWN.
•All other Brocade switches: Provide the switch WWN. Use the wwn command to display the
switch WWN.
Document feedback
Because quality is our first concern at Brocade, we have made every effort to ensure the accuracy
and completeness of this document. However, if you find an error or an omission, or you think that
a topic needs further development, we want to hear from you. Forward your feedback to:
[e-mail]
Provide the title and version number and as much detail as possible about your issue, including the
topic heading and page number and your suggestions for improvement.

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Chapter
1
Introduction to the iSCSI Gateway Service
This chapter describes the FC4-16IP blade iSCSI gateway service. The iSCSI gateway service is
supported only on the Brocade 48000 director running Fabric OS v5.2.0 or higher with one or more
iSCSI-enabled FC4-16IP blades.
In this chapter
•Supported iSCSI initiators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•Overview of iSCSI gateway service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
•Checklist for configuring iSCSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Supported iSCSI initiators
The following table lists iSCSI initiators supported by the iSCSI gateway service.
TABLE 1 supported iSCSI initiators
iSCSI initiator driver versions
Windows
•MS iSCSI initiator 2.02.
•MS iSCSI initiator 2.03.
•MS iSCSI initiator 2.04.
Linux
•RH EL 4 default initiator.
•2.6.10 - 4.0.2 iSCSI initiator (SourceForge,Net initiator).
•2.4.20 - 3.6.2 iSCSI initiator (SourceForge,Net initiator).
•SUSE 9.
•SUSE 10.
Solaris
•iSCSI is built-in the 5.11 with the latest Solaris Express release.
AIX
•iSCSI is built-in in the 5.3 ML4
HP-UX
•11i v1 - B.11.23.03e
•11 iv2 - B.11.23.03e
NIC/TOE cards
iSCSI HBAs
•Alacritech SES2002XT
•Qlogic 4050c

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Overview of iSCSI gateway service
1
Overview of iSCSI gateway service
The FC4-16IP iSCSI gateway service is an intermediate device in the network, allowing iSCSI
initiators in an IP SAN to access and utilize storage in a Fibre Channel (FC) SAN as shown in the
figure below.
FIGURE 1 iSCSI gateway network
It provides the following services to the iSCSI initiators:
•Access to the fabric using virtual FC devices (iSCSI virtual initiator)
•Supports target registration to an iSCSI Name Server (iSNS) for discovery
•Manages iSCSI initiator access control using discovery domains and a discovery domain set
•Session management, such as session tracking and performance monitoring
•Session authentication using CHAP
NOTE
The FC4-16IP iSCSI gateway service is not compatible with other iSCSI gateway platforms, including
Brocade iSCSI Gateway or the Brocade Multiprotocol Router.
FC target 1
FC target 2
iS CS I
initiator
SAN
LUNs
LUNs
FC4-16IP
iSCS I gateway
IP
network

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Overview of iSCSI gateway service 1
How iSCSI sessions are translated
The iSCSI gateway enables applications on an IP network to use an iSCSI initiator to connect to FC
targets. The iSCSI gateway translates iSCSI protocol to Fibre Channel Protocol (FCP), bridging the IP
network and FC SAN. The following figure shows a basic implementation.
FIGURE 2 iSCSI gateway service basic implementation
The Brocade FC4-16IP blade acts as an iSCSI gateway between FC-attached targets and iSCSI
initiators. On the iSCSI initiator, iSCSI is mapped between the SCSI driver and the TCP/IP stack. At
the iSCSI gateway port, the incoming iSCSI data is converted to FCP (SCSI on FC) by the iSCSI
virtual initiator, and then forwarded to the FC target. This allows low-cost servers to leverage an
existing FC infrastructure.
To represent all iSCSI initiators and sessions, each iSCSI portal has one iSCSI virtual initiator (VI) to
the FC fabric that appears as an N_Port device with a special WWN format. Regardless of the
number of iSCSI initiators or iSCSI sessions sharing the portal, Fabric OS uses one iSCSI VI per
iSCSI portal.
The following figure shows the interaction of different layers from the iSCSI initiator stack to the FC
target stack, including the iSCSI gateway service used during protocol translation.
FIGURE 3 iSCSI-to-FC translation
iS CS I
initiator
iS CS I virtual
initiator (VI)
iS CS I virtual
target (V T )
SAN
IP
network
IP
portal
FC
portal
FC 4-16IP iS C S I gateway
FC
IP
FC
target 1
FC
target 2
LUNs
LUNs
iSCS I gateway service
Storage
(device server)
SCSI
FCP
FC
FC target
Application
SCSI
iS C S I
TCP/IP
iS CS I initiator
FCP (FC-4)
FC (FC-2/FC-3)
iS C S I
TCP/IP
iS CS I virtual
initiator (VI)
iS CS I virtual
target (V T )
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Presenting FC targets as iSCSI virtual targets
Fabric OS provides the following two methods to map physical FC targets (LUNs) to iSCSI virtual
targets (VTs):
•“Basic LUN mapping”
•“Advanced LUN mapping”
Basic LUN mapping
Fabric OS provides a mechanism that maps LUNs to iSCSI VTs, a one-to-one mapping with unique
iSCSI Qualified Names (IQNs) for each target. It presents an iSCSI VT for each native FC target to
the IP network and an iSCSI VI for each iSCSI port to the FC fabric.
The following figure shows the result of using the iscsiCfg - -easycreate tgt command executed on
an FC target with four LUNs. See “Configuring the GbE interface” on page 15.
FIGURE 4 iSCSI VT basic LUN mapping
Advanced LUN mapping
SCSI VTs can be mapped to more than one physical FC target, and the LUNs can be mapped to
different virtual LUNs. The following figure shows an advanced mapping scenario.
iS CS I virtual target (VT)
2
3
0
1
LUN
FC target
2
3
0
1
LUN
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FIGURE 5 iSCSI VT advanced LUN mapping
Identifying iSCSI components
See Figure 2 for a basic implementation with an IP network. The Brocade iSCSI gateway service
supports IQN only to identify the iSCSI components, such as the iSCSI initiator and iSCSI VT. Every
iSCSI initiator and iSCSI VT on the same network and SAN must have a unique IQN.
The format of an IQN is as follows:
type.date.naming authority:<user_defined>
A Brocade-created IQN includes “2002-12.com.brocade” and the device WWN as shown in the
following example:
Type Date Auth User defined
+--++-------+ +------+ +---- -----------------+
iqn.2002-12.com.brocade:10:00:00:05:1e:aa:bb:cc
A Microsoft-created IQN includes “microsoft” and the system name:
iqn.2003-11.com.microsoft:win2k-sn-192168101
The following figure shows an iSCSI gateway that has three iSCSI VTs and two iSCSI initiators.
iS CS I virtual target 1
iS CS I virtual target 2
iS CS I virtual target 3
2
0
1
0
LUN
LUN
LUN
LUN
LUN
0
2
3
0
1
4
5
FC target 2
FC target 1
22
23
20
21
24
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FIGURE 6 IQN example
Controlling access to the iSCSI VT
You can limit access to iSCSI VTs using a discovery domain (DD), a group of the iSCSI initiators and
iSCSI VTs. The iSCSI initiators can access only the iSCSI VTs that are in the same discovery domain.
Discovery domains are grouped together in a discovery domain set (DDSet). The active discovery
domain set enforces the fabric-wide iSCSI VT access. Only the DDs in the active DDSet are
enforced. You can create multiple discovery domain sets but only one set can be active at a time.
It is also possible to present a single iSCSI portal IP address to the iSCSI initiator when the default
iSCSI port configuration is in effect, and connection redirection is disabled on the blade.
The following figure shows a discovery domain set (DDSet 1), which contains two discovery
domains (DD1 and DD2). When DDSet 1 is active, iSCSI initiator A can access only iSCSI VT 1 and
iSCSI initiator B can access only VT 2 and VT 3.
IP Network
iS CS I gateway s ervice
iS CS I virtual targets (VTs )
iS CS I initiator A
iS CS I initiator B
VT 1
VT 2
VT 3
iiqn.2003-11.com.micros oft:win2k-sn-192168102
iqn.2003-11.com.micros oft:win2k-sn-192168101
iqn.2002-12.com.brocade:10:00: 00:05:1e:aa:bb:cc
iqn.2002-12.com.brocade:10:00: 00:05:1e:cc:bb:aa
iqn.2002-12.com.brocade:10:00: 00:05:1e:bb:cc:aa