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

Publication Number: 53-1000430-01
Publication Date: 01/29/2007
Access Gateway
Administrator’s Guide
Supporting Fabric OS v5.2.1

Copyright © 2007, Brocade Communications Systems, Incorporated.
ALL RIGHTS RESERVED.
Brocade, the Brocade B weave logo, Fabric OS, File Lifecycle Manager, MyView, Secure Fabric OS, SilkWorm, and
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Document History
The following table lists all versions of the Access Gateway Set Up Guide.
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Document Title Publication
Number
Summary of Changes Publication
Date
Access Gateway
Administrator’s Guide
53-1000430-01 First version January 2007

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Publication Number: 53-1000430-01
Contents
About This Document
Supported hardware and software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
How this document is organized. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Document conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Text formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Notes, cautions, and warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Key terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Additional information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Brocade resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Other industry resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Optional Brocade features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Getting technical help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Document feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Chapter 1 Introduction to the Brocade Access Gateway
Overview of Brocade Access Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Access Gateway port types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Comparing FC port configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Port mapping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Port initialization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Failover policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Failback policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Chapter 2 Configuring Access Gateway
Verifying the fabric and edge switch settings . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

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Enabling Access Gateway mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Using Web Tools to enable Access Gateway mode . . . . . . . . . . . . . . . . . 2-2
Using the CLI to enable Access Gateway mode. . . . . . . . . . . . . . . . . . . . 2-4
Chapter 3 Disabling Access Gateway Mode
Before you begin. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Backing up the switch configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Disabling Access Gateway mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Using Web Tools to Disable Access Gateway mode . . . . . . . . . . . . . . . . 3-3
Using the CLI to disable Access Gateway mode . . . . . . . . . . . . . . . . . . . 3-4
Notes on joining the switch to a fabric . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Chapter 4 Managing Ports in Access Gateway mode
Determining the mapping and port status . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Displaying the port mapping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Displaying the port status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Configuring port maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Adding F_Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Removing F_Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Managing the failover and failback policies. . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Enabling the failover policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Enabling the failback policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
Configuring additional F_Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Unlocking N_Port mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Appendix A Default Port Mapping
Appendix B Compatibility
Appendix C Troubleshooting
Appendix D Access Gateway Commands and Messages
Access Gateway commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-2

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Access Gateway system messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-5
Index

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Access Gateway Administrator’s Guide 1
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About This Document
This document is a procedural guide to help SAN administrators configure and manage Brocade Access
Gateway.
Supported hardware and software
This document is specific to Fabric OS v5.2.1 or higher running on the Brocade SilkWorm 4012, 4016,
4020, and 4024 embedded switches.
When 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 SilkWorm models. It also specifies when
procedures or steps of procedures apply only to specific SilkWorm 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 Brocade Access Gateway,” describes the Access Gateway
operation.
•Chapter 2, “Configuring Access Gateway,” provides the initial setup procedures and fabric
requirement to deploy an Access Gateway solution.
•Chapter 3, “Disabling Access Gateway Mode,” provides instructions on disabling Access Gateway
mode so that the switch can be used as a fabric switch.
•Chapter 4, “Managing Ports in Access Gateway mode,” provides instructions on changing N_Ports
to F_Ports, mapping F_Ports to N_Ports, and changing failover and failback policies.
The appendices provide the default mappings, compatibility 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.
Caution
A caution alerts you to potential damage to hardware, firmware, software, or data.
Warning
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 Access Gateway mode and its components.
Access Gateway (AG) Fabric OS mode for embedded switches that reduces SAN (storage area
network) deployment complexity by leveraging NPIV (N_Port ID
virtualization).
Edge switch Fabric switch that connects host, storage, or other devices, such as Brocade
Access Gateway, to the fabric.
NPIV N_Port ID virtualization. Allows a single Fibre Channel port to appear as
multiple, distinct ports providing separate port identification and security
zoning within the fabric for each operating system image as if each operating
system image had its own unique physical port.
E_Port An ISL (InterSwitch link) port. A switch port that connects switches together
to form a fabric.
F_Port A fabric port. A switch port that connects a host, HBA (host bus adaptor), or
storage device to the SAN. On Brocade Access Gateway, the F_Port connects
to a host only.
N_Port A node port. A Fibre Channel host or storage port in a fabric or point-to-point
connection. On Brocade Access Gateway, the N_Port connects to the edge
switch.
mapping On Brocade Access Gateway, the configuration of F_Port to N_Port routes.
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.
The following documentation is available for Fabric OS:
•Fabric OS v5.2.x Software Addendum
•Fabric OS Administrator’s Guide
•Fabric OS Command Reference
Note
Go to http://www.brocade.com and CLIck Brocade Connect to register at no cost for a user ID and
password.

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•Fabric OS MIB Reference
•Fabric OS Message Reference
•Web Tools Administrator’s Guide
•Brocade Glossary
The following documentation is available for SilkWorm embedded switches:
•SilkWorm 4016 Hardware Reference Manual
•SilkWorm 4016 QuickStart Guide
•SilkWorm 4020 Hardware Reference Manual
•SilkWorm 4020 QuickStart Guide
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.
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.

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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.
:
The serial number label is located as follows:
•SilkWorm 3014—On the top of the chassis, under the insertion arm
•SilkWorm 3016 and 4012—On the bottom of the switch module
•SilkWorm 4018—On the top of the blade
•SilkWorm 200E, 3200, 3250 and 3850—On the bottom of the chassis
•SilkWorm 3800 and 3900—Nonport side of the chassis
•Brocade 5000, SilkWorm 4100, 4900, and 7500—On the switch ID pull-out tab located inside
the chassis on the port side on the left
•SilkWorm 4016—Top of the switch module
•SilkWorm 4024—Bottom of the switch module
•SilkWorm 12000, 24000, and 48000—Inside the chassis next to the power supply bays
•SilkWorm Multiprotocol Router Model AP7420—On the bottom of the chassis and on the back
of the chassis.
*FT00X0054E9*
FT00X0054E9

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3. World Wide Name (WWN)
•Brocade 5000, SilkWorm 200E, 3014, 3016, 3250, 3800, 3850, 3900, 4012, 4018, 4020, 4024,
4100, 4900, and 7500 switches and SilkWorm 24000, and 48000 directors: Provide the license
ID. Use the licenseIdShow command to display the license ID.
•SilkWorm Multiprotocol Router Model AP7420: Provide the switch WWN. Use the
switchShow command to display the switch WWN.
•All other SilkWorm 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:
[email protected]
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 Brocade Access Gateway
This chapter describes the functions of Brocade Access Gateway. The SilkWorm 4012, 4016, 4020, and
4024 embedded switches running Fabric OS v5.2.1 or higher support Access Gateway (AG).
The chapter covers the following topics:
•“Overview of Brocade Access Gateway” on page 1-1
•“Access Gateway port types” on page 1-2
•“Port mapping” on page 1-4
•“Port initialization” on page 1-5
•“Failover policy” on page 1-6
•“Failback policy” on page 1-7
Overview of Brocade Access Gateway
Brocade Access Gateway allows multiple hosts (or HBAs) to access the fabric using fewer physical
ports. Access Gateway mode transforms an embedded switch into a device management tool that is
compatible with different types of fabrics, including Brocade-, Cisco-, and McDATA-based fabrics (see
the matrix in Appendix B, “Compatibility” for more details).
When a switch is in Access Gateway mode, it is logically transparent to the host and the fabric. Brocade
Access Gateway modes allows hosts to access the fabric without increasing the number of switches and
simplifies configuration and management in a large fabric by reducing the number of domain IDs and
ports.
Brocade Access Gateway is a device management tool and provides only a subset of Fabric OS
commands. It does not consume critical fabric elements that could inhibit scalability. For example, a
fabric that uses Access Gateways to connect hosts requires fewer domain IDs.

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Access Gateway port types
1
The following figure compares a configuration that connects eight hosts to the fabric using Brocade
Access Gateway to the same configuration with standard fabric switches.
Figure 1-1 Access Gateway and fabric switch comparison
The difference between the fabric switch (Fabric OS native mode) and Brocade Access Gateway is as
follows:
•The Fabric OS switch is a part of the fabric; it requires two through four times as many physical
ports, consumes fabric resources, and can connect to a Brocade-based fabric only.
•Brocade Access Gateway is outside the fabric; it reduces the number of switches on the fabric and
the number of required physical ports. You can connect Brocade Access Gateway to either a
Brocade-, Cisco-, or McDATA-based fabric.
Access Gateway port types
Brocade Access Gateway differs from a typical fabric switch because it connects to the fabric using
node ports (N_Ports). Typically fabric switches connect to the enterprise fabric using ISL (InterSwitch
Link) ports, such as an E_Port.
The following defines the Fibre Channel (FC) port terms used in this manual:
•F_Port, fabric port. A switch port that connects a host, HBA, or storage device to the SAN.
•N_Port, node port. A host, HBA, or storage device port that connects to the F_Port of the
fabric switch.
Note
When using a Brocade blade server embedded switch in Access Gateway mode, most switch features are
no longer applicable. These features include Admin Domains, Advanced Performance Monitoring,
direct connection to SAN target devices, Fibre Channel Arbitrated Loop support, Fabric Manager,
FICON, IP over FC, ISL Trunking, Extended Fabrics, Management Services, Name Services (SNS),
port mirroring, Secure Fabric OS, SMI-S, and Zoning. These switch features are available in the default
switch mode of operation.

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Access Gateway port types 1
Comparing FC port configurations
Brocade Access Gateway multiplexes host connections to the fabric. It presents an F_Port to the host
and an N_Port to an edge fabric switch. Using N_Port ID virtualization (NPIV), Brocade Access
Gateway allows multiple FC initiators to access the SAN on the same physical port. This reduces the
hardware requirements and management overhead of hosts to the SAN connections.
A fabric switch presents F_Ports (or FL_Ports) to the host and storage devices and presents E_Ports,
TE_Ports, or EX_Ports to other switches in the fabric. A fabric switch consumes SAN resources, such
as domain IDs, and participates in fabric management and zoning distribution. A fabric switch requires
more physical ports than Brocade Access Gateway to connect the same number of hosts.
Figure 1-2 compares the types of ports used by the Access Gateway to those used by a typical fabric
switch.
Figure 1-2 Port usage comparison
Table 1-1 Compares port configuration between Access Gateway with a typical fabric switch.
Table 1-1 Port Configurations
Port Type Access Gateway Fabric switch
F_Port Yes Connects hosts to Brocade
Access Gateway.
Yes Connects devices, such as hosts,
HBAs, and storage to the fabric.
N_Port Yes Connects Access Gateway to a
fabric switch.
NA N_Ports are not supported.
E_Port NA ISL is not supported.1
1. The switch is logically transparent to the fabric, therefore it does not participate in the SAN as a fabric switch.
Yes Connects the switch to other switches
to form a fabric.
N_Port F_Port
N_Port
F_Port
N_Port F_Port
Hosts Access Gateway
Edge Switch
Fabric
enabled
NPIV
N_Port
F_Port E_Port
E_Port
N_Port
F_Port
Hosts Edge Switch Fabric Switch
E_Port
E_Port
Fabric
Access Gateway Ports
Fabric Switch Ports

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Port mapping
1
Port mapping
Brocade Access Gateway uses mapping—that is, pre-provisioned routes—to direct traffic from the
hosts to the fabric. When you first enable Access Gateway mode, the F_Ports are mapped to a set of
predefined N_Ports, see Appendix A, “Default Port Mapping”. After the initial setup, you can manually
change the mapping if required.
Figure 1-3 shows a mapping with eight F_Ports evenly mapped to four N_Ports on Brocade Access
Gateway. The N_Ports connect to the same fabric via different edge switches. This example is also used
to explain mapping, failover, and failback polices.
Figure 1-3 Example F_Port to N_Port mapping
The following table describes the mapping and fabric connection shown in Figure 1-3:
Table 1-2 Example port mapping
Access Gateway Fabric
N_Port F_Port Edge switch F_Port
N_1 F_1, F_2 Switch_A F_A1
N_2 F_3, F_4 Switch_A F_A2
N_3 F_5, F_6 Switch_B F_B1
N_4 F_7, F_8 Switch_B F_B2
N_2
F_A2
Hosts Access Gateway
Edge Switch
Fabric
(Switch_A)
enabled
NPIV
F_4
F_3
F_2
F_1
N_1
F_A1
enabled
NPIV
N_3
F_B1
enabled
NPIV
Host_1
Host_2
Host_3
Host_4
F_5
Host_5
F_6
Host_6
F_7
Host_7
F_8
Host_8
Edge Switch
(Switch_B)
N_4
F_B2
enabled
NPIV

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Port initialization 1
Port initialization
To ensure that all hosts are brought online when Brocade Access Gateway starts up, the ports are
initialized in the following manner:
1. All N_Ports are initialized. During N_Port initialization all the F_Ports are disabled (kept
OFFLINE).
The ports are enabled or disabled as follows:
•Enabled (online) if the port receives a fabric login event and is connected to an F_Port of an
edge switch that supports NPIV (N_Port ID virtualization).
•Disabled (offline) if the port is not connected to a fabric or is connected to a fabric port that
does not support NPIV.
2. All F_Ports mapped to online N_Ports are enabled. F_Ports that are inactive or that have no hosts
are disabled.
3. F_Ports mapped to an offline N_Port with the failover policy enabled fail over to an online N_Port.
4. The host logs in to the fabric as follows:
a. The host sends a FLOGI (fabric login) request.
b. Access Gateway proxies the request using FDISC primitive to the fabric with the same
parameters as the host.
c. The fabric processes the request and sends an FDISC response.
d. Access Gateway proxies the response to the host using the same parameters as the fabric.
e. The host receives the response from the fabric.
After ports are initialized, Access Gateway becomes logically transparent to the host and the
fabric, as shown in Figure 1-4.
Figure 1-4 Host log in request
abc
d
e

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Failover policy
1
Failover policy
The Brocade Access Gateway N_Port failover policy allows hosts to automatically remap to an online
N_Port if the N_Port they are connected to goes offline. The failover policy evenly distributes the
F_Ports that are mapped to an offline N_Port among all the online N_Ports. The failover policy is a
parameter of each N_Port. By default, the failover policy is enabled for all N_Ports.
The following sequence describes how a failover event occurs:
1. An N_Port goes offline.
2. All F_Ports mapped to that N_Port are disabled.
3. If the N_Port failover policy is enabled, the disabled F_Ports are remapped to an online N_Port.
The F_Ports are evenly distributed among the remaining online N_Ports.
4. The F_Port is re-enabled on the new N_Port.
5. The host establishes a new connection with the fabric.
Example: Failover Policy
This example shows the failover behavior in a scenario where two fabric ports go offline, one after the
other.
•First the edge switch F_A1 port goes offline, as shown in Figure 1-5 example 1 (left), causing the
corresponding Access Gateway N_1 port to be disabled.
The ports mapped to N_1 fail over; F_1 fails over to N_2 and F_2 fails over to N_3.
•Next the F_A2 port goes offline, as shown in Figure 1-5 example 2 (right), causing the
corresponding Access Gateway N_2 port to be disabled.

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Failback policy 1
The ports mapped to N_2 (F_1, F_3, and F_4) failover to N_3 and N_4. Note that the F_Ports are
evenly distributed to the remaining online N_Ports and that the F_2 did not participate in the
failover event.
Figure 1-5 Example 1 and 2 failover policy behavior
Failback policy
The Brocade Access Gateway failback policy automatically reroutes the F_Ports back to the originally
mapped N_Ports as those N_Ports come back online.
Only the originally mapped F_Ports fail back. In the case of multiple N_Port failures, only F_Ports that
were mapped to the recovered N_Port experience failback. The remaining F_Ports are not redistributed
among the online N_Ports during the failback.
The following sequence describes how a failback event occurs:
1. When an N_Port comes back online, the F_Ports that were originally mapped to it are disabled.
2. The F_Port is reenabled on the original N_Port.
F_A2
Hosts Access Gateway
Edge Switch
Fabric
(Switch_A)
enabled
NPIV
F_4
F_3
F_2
F_1
N_1
F_A1
enabled
NPIV
N_3
F_B1
enabled
NPIV
Host_1
Host_2
Host_3
Host_4
F_5
Host_5
F_6
Host_6
F_7
Host_7
F_8
Host_8
Edge Switch
(Switch_B)
N_4
F_B2
enabled
NPIV
N_2
Legend
Physical connection
Mapped online
Failover route online
Original mapped route
(offline)
Example 1
F_A2
Hosts Access Gateway
Edge Switch
Fabric
(Switch_A)
enabled
NPIV
F_4
F_3
F_2
F_1
N_1
F_A1
enabled
NPIV
N_3
F_B1
enabled
NPIV
Host_1
Host_2
Host_3
Host_4
F_5
Host_5
F_6
Host_6
F_7
Host_7
F_8
Host_8
Edge Switch
(Switch_B)
N_4
F_B2
enabled
NPIV
Example 2
N_2
Note
The failback policy is an N_Port parameter. The failback policy is enabled by default.

1-8 Access Gateway Administrator’s Guide
Publication Number: 53-1000430-01
Failback policy
1
3. The host establishes a new connection with the fabric.
Example: Failback Policy
In Example 3, the Brocade Access Gateway N_1 remains disabled because the corresponding F_A1
port is offline. However N_2 comes back online. (See Figure 1-5 for the original failover scenario.)
The ports mapped to N_1 (F_1 and F_2) continue to be routed to N_3; the ports originally mapped to
N_2 (F_3 and F_4) are disabled, rerouted to N_2, and then enabled.
Figure 1-6 Failback policy behavior
F_A2
Hosts Access Gateway
Edge Switch
Fabric
(Switch_A)
enabled
NPIV
F_4
F_3
F_2
F_1
N_1
F_A1
enabled
NPIV
N_3
F_B1
enabled
NPIV
Host_1
Host_2
Host_3
Host_4
F_5
Host_5
F_6
Host_6
F_7
Host_7
F_8
Host_8
Edge Switch
(Switch_B)
N_4
F_B2
enabled
NPIV
N_2
Legend
Physical connection
Mapped online
Failover route online
Original mapped route
(offline)
Example 3