76359902 Introduction to Fiber Channel

7/30/2019 76359902 Introduction to Fiber Channel

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Copyright 2005 EMC Corporation. Do not Copy - All Rights Reserved.

Introduction to Fibre Channel - 1

2005 EMC Corporation. All rights reserved.

Introduction to Fibre ChannelIntroduction to Fibre Channel

Welcome to Introduction to Fibre Channel.

The AUDIO portion of this course is supplemental to the material and is not a replacement forthe student notes accompanying this course. EMC recommends downloading the StudentResource Guide from the Supporting Materials tab, and reading the notes in their entirety.

Copyright 2005 EMC Corporation. All rights reserved. These materials may not be copied without EMC'swritten consent. Use, copying, and distribution of any EMC software described in this publication requires anapplicable software license.

THE INFORMATION IN THIS PUBLICATION IS PROVIDED AS IS. EMC CORPORATION MAKES NOREPRESENTATIONS OR WARRANTIES OF ANY KIND WITH RESPECT TO THE INFORMATION IN THISPUBLICATION, AND SPECIFICALLY DISCLAIMS IMPLIED WARRANTIES OF MERCHANTABILITY ORFITNESS FOR A PARTICULAR PURPOSE.

Celerra, CLARalert, CLARiiON, Connectrix, Dantz, Documentum, EMC, EMC2, HighRoad, Legato, Navisphere,PowerPath, ResourcePak, SnapView/IP, SRDF, Symmetrix, TimeFinder, VisualSAN, where information lives areregistered trademarks.

Access Logix, AutoAdvice, Automated Resource Manager, AutoSwap, AVALONidm, C-Clip, Celerra Replicator,Centera, CentraStar, CLARevent, CopyCross, CopyPoint, DatabaseXtender, Direct Matrix, Direct MatrixArchitecture, EDM, E-Lab, EMC Automated Networked Storage, EMC ControlCenter, EMC Developers Program,EMC OnCourse, EMC Proven, EMC Snap, Enginuity, FarPoint, FLARE, GeoSpan, InfoMover, MirrorView,NetWin, OnAlert, OpenScale, Powerlink, PowerVolume, RepliCare, SafeLine, SAN Architect, SAN Copy, SANManager, SDMS, SnapSure, SnapView, StorageScope, SupportMate, SymmAPI, SymmEnabler, Symmetrix DMX,Universal Data Tone, VisualSRM are trademarks of EMC Corporation. All other trademarks used herein are theproperty of their respective owners.


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2005 EMC Corporation. All rights reserved. Introduction to Fibre Channel - 2

Course Objectives

Upon completion of this course, you will be able to:

yUnderstand the Fibre Channel Architecture

y Identify the different Fibre Channel layers

y Learn Fibre Channel Topologies

y Know SAN concepts

The objectives for this course are shown here. Please take a moment to read them.


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Lesson 1 Fibre Channel Overview

Upon completion of this lesson, you will be able to:

yKnow the Fibre Channel characteristics and utilities

y Learn different Network Storage Technologies usingFibre Channel

y Identify management tools in a SAN environment

The objectives for this lesson are shown here. Please take a moment to read them.


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Fibre Channel

y Fibre Channel is a serial data transfer interface intendedfor connecting high-speed storage devices to computers

yThe high-speed is obtained through of the processfollowing: Networking and I/O protocols (such as SCSI commands) are

mapped to Fibre Channel constructs

And encapsulated and transported withinFibre Channel frames

With this is possible high-speed transfer of

multiple protocols over the same physicalinterface

Fibre Channel is a serial data transfer interface that operates over copper wire and/or optical

fiber at data rates up to 200 MB/s (megabytes per second).

Networking and I/O protocols (such as SCSI commands) are mapped to Fibre Channel

constructs, and then encapsulated and transported within Fibre Channel frames. This process

allows high-speed transfer of multiple protocols over the same physical interface.

Fibre Channel systems are assembled from familiar types of components: adapters, hubs,

switches and storage devices.

Host bus adapters are installed in computers and servers in the same manner as a SCSI host bus

adapter or a network interface card (NIC).

Hubs link individual elements together to form a shared bandwidth loop.

Fibre Channel switches provide full bandwidth connections for highly scalable systems without

a practical limit to the number of connections supported (16 million addresses are possible).

The word fiber indicates the physical media. The word fibre indicates the Fibre Channel

protocol and standards.


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Channels

yThe channel connections, such as parallel bus and tag,ESCON, and SCSI provide fixed connections betweenhost systems and their peripheral devices

y Some characteristics of channel technologies are:

High performance

Low protocol overhead

Static configuration

Short distance (although ESCON is somewhat of an exception)

Connectivity within a single system

Traditionally, host computer operating systems have communicated with storage devices over

channel connections, such as parallel bus and tag,

ESCON, and SCSI. These channel technologies provide fixed connections between host systems

and their peripheral devices.

The static connections are defined to the operating system in advance. Tight integration between

the transmission protocol and the physical interface minimizes the overhead required to

establish communication and transport large amounts of data to the statically defined devices.

Some characteristics of channel technologies are:

y High performance

y Low protocol overheady Static configuration

y Short distance (although ESCON is somewhat of an exception)

y Connectivity within a single system


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Network

yThe network technologies offer more flexibility anddistance capabilities than channel technologies

y Some characteristics of network technologies are:

Low performance

High protocol overhead

Dynamic configuration

Long distance

Connectivity among different systems

Network technologies are more flexible than channel technologies, and provide greater distance

capabilities. Most networks provide connectivity between client or host systems, and carry a

variety of data between the devices. A simple example is a network of desktop PCs within a

company.

This type of setup can provide each PC with connectivity to file and print services, server-based

applications, and corporate intranets.

The networks these PCs are connected to provide shared bandwidth and the ability to

communicate with many different systems. This flexibility results in greater protocol overhead

and reduced performance.

Some characteristics of network technologies are:

y Low performance

y High protocol overhead

y Dynamic configuration

y Long distance

y Connectivity among different systems


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y Fibre Channel capturessome of the benefits ofboth channels andnetworks

y Fibre Channel standardsdefine layeredcommunicationsarchitecture similar to

other networkingenvironments

Fibre Channel: Channels with NetworkCharacteristics

Channels

(benefits)

Networks

(benefits)

Fibre Channel

Fibre Channel captures some of the benefits of both channels and networks. A Fibre Channel

Fabric is a switched network, providing a set of generic, low-level services onto which host

channel architectures and network architectures can be mapped.

Fibre Channel standards define a layered communications architecture similar to other

networking environments. Each level of the Fibre Channel protocol stack provides a specific set

of functions.


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Network Storage Technologies

Typical

applications

Type of data

Key requirement

Type of transport

OLTP, datawarehousing, ERP

Fibre Channel(FCP, FICON)IP (iSCSI, FCIP,iFCP)

Block

Deterministic

performance

NASNetwork-AttachedStorage

Software and productdevelopment, fileserver consolidation

File

Multi-protocol

sharing

IP, Fibre Channel(*MPFS)

CASContent AddressedStorage

Contentmanagement

Longevity,

integrity assurance

IP

Object,fixed content

SANStorage AreaNetworks

Fibre Channel integrates the SAN (Storage Area Networks) and NAS (Network-Attached

Storage) solutions.


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Lesson 2 - Fibre Channel Concepts


yUnderstand how the Fibre Channel standards are defined

y Know attributes of FC-0, FC-1, and FC-2

y Identify the roles of FC-3 and FC-4 in Fibre Channelprotocol



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FC-0

yThe FC-0 level of FC-

PH describes the FibreChannel link

Physical Interface

Optical and ElectricalInterfaces

Cables, Connectors, etc

y Each fiber is attached

to a transmitter of aPort at one end and areceiver of anotherPort at the other end

FC-1FC-1

FC-3FC-3

FC-2FC-2

Fibre Channel Level 0 (FC0)Fibre Channel Level 0 (FC0)

ULPULP

FC-4FC-4

The FC-0 level describes the Fibre Channel link. It covers a variety of media and the associated

drivers and receivers capable of operating at a wide range of speeds. It is designed for maximum

flexibility and allows the use of a large number of technologies to meet the widest range of

system requirements.

Each fiber is attached to a transmitter of a Port at one end and a receiver of another Port at the

other end. When a Fabric is present in the configuration, a fiber may attach to an N_Port and an

F_Port. Patch panels or portions of the active Fabric may function as repeaters, concentrators or

fibre converters.


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Connectors

yThe LC assembly designincorporates an RJ -style latchin a connector body with halfthe footprint of a conventionalSC

yThe SC connector is thestandard connector for fiber

optic cables. It is a push-pullconnector

The LC assembly design incorporates an RJ-style latch in a connector body with half the

footprint of a conventional SC. High-precision, 1.25 mm ceramic ferrules and engineered

composites provide a durable package with consistent, repeatable performance.

The SC connector is the standard connector for fiber optic cables. It is a push-pull connector and

is favored over the ST connector (commonly used in patch panels). If the cable is pulled, the tip

of the cable in the connector does not move out, which would result in loss of signal quality.


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Multi-Mode Cable

y Multi-mode transmitters send multiple short-wavelengthsignals through the same fiber

yThe angle of entry is high and the signals tend to canceleach other out

y Multimode fiber has a larger diameter (62.5 or 50microns) core than single-mode fiber

Multimode cable is dominant for short distances of 500 meters or less. Multimode has an inner

diameter of 62.5 or 50 microns, allowing light to enter the cable in multiple modes, including

straight and at different angles. The many light beams tend to lose shape as they move down the

cable. This loss of shape is called modal dispersion and limits the distance.


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Single-Mode Cable

y Single-mode transmitters send one longer-wavelengthsignal down a much thinner-cored fiber

yThe angle of entry is low (less bouncing) and there is littleto muddy the signal, hence the much greater distances

y Single mode cable has an inner diameter of 9 microns

Single mode cable is used for long distance cable runs, only limited by the power of the laser at

the transmitter and by the sensitivity of the receiver. Single mode cable has an inner diameter of

9 microns and is always used with a long wave laser, which limits the effects of modal

dispersion. Therefore, with single mode cables the distance is greatly increased.


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HBA (Host Bus Adapter)

y An HBA is any adapter that allows a computer bus toattach to another bus or channel

y A Host Bus Adapter performs many low-level interfacefunctions automatically to minimize the impact on hostprocessor performance

yThe HBA enables a range of high-availability and storage managementcapabilities

Load balance

Fail-over

SAN administration

Storage management

An HBA is an I/O adapter that sits between the host computer's bus and the Fibre Channel loop,

and manages the transfer of information between the two channels. In order to minimize the

impact on host processor performance, the host bus adapter performs many low-level interface

functions automatically or with minimal processor involvement.

In simple terms, a host bus adapter (HBA) provides I/O processing and physical connectivity

between a server and storage. The storage may be attached using a variety of direct attached or

storage networking technologies, including Fibre Channel, iSCSI, VI/IP, FICON, or SCSI. Host

bus adapters provide critical server CPU off-load, freeing servers to perform application

processing. As the only part of a storage area network that resides in a server, HBAs also

provide a critical link between the SAN and the operating system and application software. In

this role, the HBA enables a range of high-availability and storage management capabilities,

including load balancing, fail-over, SAN administration, and storage management.


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FC-1

y Defines the method

used to Encode dataprior to transmissionand decode the dataupon reception

y A benefit of using8b/10b encoding is thatit defines a number of

Special Characters Fibre Channel Level 1 (FC1)Fibre Channel Level 1 (FC1)


Whenever the encoder creates a character with more ones than zeros, it remembers this by

setting a single-bit variable called the Current Running Disparity (CRD) to positive. Whenever

the encoder creates a character with more zeros than ones, it sets the CRD to negative.

The CRD is fed back to the encoder to select the appropriate encoding in order to balance the

number of ones and zero bits transmitted.

As a series of characters are processed, the output alternates between positive and negative

disparity.


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Encoding Process

yThe encoding process transforms 8-bit input charactersinto 10-bit transmission characters having the desiredattributes

The encoding process transforms 8-bit input characters into 10-bit transmission characters

having the desired attributes. Not all of the possible 10-bit patterns are used. 10 bits allow 1024

different combinations.

To prevent excessive DC (direct current) components and run length problems, only characters

containing 6 ones and 4 zeros, 5 ones and 5 zeros, or 4 ones and 6 zeros are used. Any other

weighting of bits is invalid.

y 5 ones and 5 zeros are considered to have neutral disparity

y 6 ones and 4 zeros are considered to have positive disparity

y 4 ones and 6 zeros are considered to have negative disparity

y All possible 8-bit characters have 2 possible 10-bit encodings

This is the same method used to transmit a data stream in ESCON. The purpose of this is to

break up the data stream in the serial environment and at the same time allow control characters

to be embedded into the stream to speed up communications.


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Ordered Sets

yTwo types of Transmission Characters (Data andSpecial) are defined

Data Field

Header

OptionalHeader

OptionalHeader

Payload(information being

Transported

FillBytes

IDLE

Two types of Transmission Characters (Data and Special) are defined. Certain combinations of

Transmission Characters, referred to as Ordered Sets, are designated to have special meaning.

Ordered Sets are used to identify frame boundaries, transmit primitive function requests, and

maintain proper link transmission characteristics during periods of inactivity.


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FC-2

y Defines the structure ofthe Fibre Channelframe

yThe transported data istransparent to FC-2and visible to FC-3 andabove




The FC-2 level serves as the transport mechanism of the Fibre Channel. The transported data is

transparent to FC-2 and visible to FC-3 and above.


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Frames

y Frames are the basic building blocks of a Fibre Channelconnection

y All information in Fibre Channel is passed in frames

Data Field

Header

OptionalHeader

OptionalHeader

Payload (informationbeing Transported

Fill BytesStart-of-Frame

CRC

End-of-Frame

Frames are the basic building blocks of a Fibre Channel connection. The frames contain the

information to be transmitted, the addresses of the source and destination ports, and link control

information.

All information in Fibre Channel is passed in frames. The maximum amount of data carried in a

frame is 2112 bytes, with a total frame size of 2148 bytes. The general structure of a Frame is

specific.


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Header Contents

yThe header contains the Source and DestinationAddresses which allows the frame to be routed to thecorrect port

Data Field

Header

OptionalHeader

OptionalHeader

Payload (informationbeing Transported

Fill BytesStart-of-Frame

CRC

End-of-Frame

Parameter Field (PARM)

OX_IDOX.ID

DF_CTLDF_CTLSEQ_ID

Frame Control (F_CNT)TYPE

Source Address (S-ID)CS_CTL

Destination Address (D-1D)R_CTL

The Header contains the Source and Destination Addresses, which allows the frame to be routed

to the correct port. The Type field interpretation is dependent on whether the frame is a link

control frame or a Fibre Channel data frame. For example, if the frame is a data frame, a 08 in

the type field would indicate SCSI FCP information in the Data field.


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Exchange and Sequences

y An Exchange is a unidirectional or bi-directional set ofnon-concurrent Sequences

y FC-2 manages Exchanges that map directly to operations

y A Sequence is contained within an Exchange and iscomprised of one or more Frames

yThe purpose of the Sequence is to reorder data when it isreceived at the other end

An Exchange is a unidirectional or bi-directional set of non-concurrent Sequences. An Exchange

is the largest construct understood by FC-2. FC-2 manages Exchanges that map directly to

operations.

FC-2 manages Sequences as unidirectional transfers of one or more frames. A Sequence is

contained within an Exchange and is comprised of one or more Frames. FC-2 names each

Sequence and tracks each Sequence to completion. The purpose of the Sequence is to reorder

data when it is received at the other end.


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Buffer to Buffer Credit

y R_RDY is sent to a transmitting node as buffers arecleared.

y An FC switch also performs buffering and flow controlinternally and externally

Data Frame

R_RDY

Data Frame

R_RDY

N_Port N_PortSwitch

The FC-2 provides flow control for buffer management. When nodes initialize on the Fabric

they agree on operational parameters such as the number of buffers available (Buffer Credits).

Transmitting nodes can continue to transmit as long as there are buffer credits. An R_RDY is

sent to a transmitting node as buffers are cleared. An FC switch also performs buffering and

flow control internally and externally.


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Classes of Service

Classes of Service

Functions Class 1 Class 2 Class 3 Class 4 Class 5

Fabric discards Frames

Communications type between ports 1:1 1 to Many 1:1

Initial roundtrip delay 3Hunt group support Optional

Multicast support Optional

Broadcast support Optional

Stacked connect Request Optional Optional

Dedicated Simplex Optional Optional

Camp-on Optional Optional

Buffered Class Optional Optional

Unidirectional Connection Optional 3End-to-End flow con trol 3 3 3 3Buffer-to-Buffer flow control 3 3 3Fabric can reject frames 3 3Fabric busies frames 3Delivery Order Guaranteed 3 3 3Nx_Port supports Class of service Optional

Fabric support Class of service Optional

Classes of Service are different types of topology independent services provided by the Fabric

and used by the communicating N_Ports destination. The allocation and retention method

between the N_Ports and the level of delivery integrity required for an application distinguish

classes of service. If the Fabric is not present, the service is provided as a special case of point-

to-point. Fabrics and N_Ports are not required to support all Classes of service.


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Fibre Channel addressing

y Fibre Channel Addresses are required to route theframes from source to target

y 24 bits (3 bytes) physical addresses are assigned whena Fibre Channel node is connected to the switch (or loopin the case of FC-AL)

Source

Target

FC Initiator:

HBA

FC Responder:

Symmetrix FA

Or

CLARiiON SP Ports

FC Switch

Fibre Channel addresses are used to designate the source and destination of frames in the Fibre

Channel network. The Fibre Channel address field is 24 bits /3 bytes in length. Unlike Ethernet,

these addresses are not burned in, but are assigned when the node either enters the loop or is

connected to the switch. There are reserved addresses, which are used for services rather than

interface addresses.


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Addressing layout

yThe Physical Address is switch specific and dynamicallygenerated in the Fabric Login (FLOGI)

y Each N_Port has a Fabric-unique identifier, with thefollowing layout

Switch Port in Switch AL_PA

02 1F 00

FC-SW FC-AL

The actual physical address is vendor and switch specific. Refer to the switch manufacturers

documentation to determine how port addressing is configured.

FLOGI will be discussed later in this lesson.

Address identifiers are three bytes in length. The Frame Header contains two three-byte fields

for address identifiers, the (D_ID) field and the (S_ID) field. Each N_Port has a Fabric-unique

identifier, the N_Port Identifier, by which it is known. The source and destination N_Port

Identifiers and alias address identifiers are used to route frames within the Fabric.


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Addressing layout

1. Domain ID - Identifies the source or target switch insidethe Fabric

2. Switch Port - Identifies the source or target port in theswitch3. AL_PA - Used in Private Loop environment, identifying

the NL_Port (node loop port)

FC-SW FC-AL

Switch

02

Switch

1F

Port in Switch

1F

AL_PA

12

AL_PA

12

Switch

021 2 3

The most significant 8 bits of the Fibre Channel address contain the Domain ID, which basically

identifies the switch. In the Fabric environment, this allows frames to be routed between

switches.

The middle 8 bits contain the area address, which has been implemented as the port address

within the switch. In the Fabric environment, this allows frames to be routed between switches.

In the Private Loop environment, the Domain and Area fields contain zeros, and the Port field

contains the AL_PA (Arbitrated Loop Physical Address) for the NL_Port.

NOTE: With a McDATA switch, the third byte will always be 13.


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World Wide Name

y A World Wide Name, or WWN, is a 64-bit address used inFibre Channel networks to uniquely identify each elementin the network

y Assigned to a host bus adapter (HBA) or switch port bythe vendor at the time of manufacture, it is similar to theMAC address in an Ethernet network

1 0 0 0 0 0 0 0 C 9 2 0 D C 4 0Example: Emulex HBAs World Wide Name

Reserved

12 bits

Company OUI

23 bits

Vendor Assigned

24 bits

A World Wide Name, or WWN, is a 64-bit address used in Fibre Channel networks to uniquely

identify each element in the network.

Assigned to a host bus adapter (HBA) or switch port by the vendor at the time of manufacture, it

is similar to the MAC address in an Ethernet network.

There are two designations of WWN; World Wide Port Name and World Wide Node Name.

Both are globally unique 64-bit identifiers. The difference lies in where each value is

physically assigned. For example, a server may have dual HBAs installed, thus having

multiple ports or connections to a SAN. A WWPN is assigned to each physical port.

The WWNN represents the entire server, which can be referred to as the node or node process,

and is derived from one of the WWPNs. EMC uses the WWPN for all configurations

Fibre Channel specifications allow for multiple formats of the World Wide Name. The example

shown is that of the IEEE Registered Name Format.

NAA is the Name Assignment Authority, which assigns the 24 bits (IEEE Company ID) to the

specific vendor (i.e. EMC).

Values for World Wide Name formats are based on the IEEE company_id. More information on

these formats can be found at www.standards.ieee.org.


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World Wide Name Target (FA and SP ports)

y Symmetrix and CLARiiON ports are soft-assigned basedon slot number, processor, port and array serial number

5 0 0 6 0 4 8 2 E 8 9 1 2 B 9 0Example: Symmetrix FA World Wide Name

5 0 0 6 0 1 6 0 0 0 6 0 0 1 B 2Example: CLARiiON SP World Wide Name

The WWNs for Symmetrix FA and CLARiiON SP ports are soft-assigned, so they will remain

unchanged after a component replacement.


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World Wide Name Symmetrix Target

y Symmetrix 8000 and previous

5 0 0 6 0 4 8 2 E 8 9 1 2 B 9 00101 0000 0000 0110 0000 0100 1000 0010 1110 1000 1001 0001 0010 1011 10 0 1

EMC Company ID 24 bits Symmetrix Serial Number 30 bits Port Side FA 4 bits

001011101000100100010010101110 011110

195183790 15bA

1110

y Symmetrix DMX

Symmetrix Serial Number 29 bits010

2CB187900106

10000101011001100110010000011001010

Half FA 4 bitsSidePortEMC Company ID 24 bits01 00011000100011100011001100110011000010000000110000000000101

5 0 0 6 0 4 8 A C C C 8 3 2 A 1

Because the WWN of the FA is dependent on the Symmetrix Serial Number and the Slot rather

than being burned in, the WWN stays constant if the FA fails and has to be replaced. To

determine the WWN of an FA depends on the version of the Symmetrix being used. The

original calculation was that the last 6 bits of the WWN were used. Bit position 6 specified the

port (0 or 1), Bit position 5 the processor ( 0-A/1-B ) and Bit position 1-4 the slot (add 1 to get

the adapter).

On the DMX series, the ports are laid out as follows, from the top down:

DB - processor 4, port 1

DA - processor 4, port 0

CB - processor 3, port 1

CA - processor 3, port 0

BB - processor 2, port 1

BA - processor 2, port 0

AB - processor 1, port 1

AA - processor 1, port 0


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The new calculation had to be both backward compatible with previous Symmetrix versions,

and at the same time allow for more addresses. The new calculation borrows a bit from the

serial number. It was determined that we do not need 30 bits for a serial number, 29 gives us all

the range we need. So, bit position 30 is now dubbed a "half bit" The half bit determines which

pair of processor we are working with. It is set to 0 for processors A & B, and 1 for C & D.

Then, as above, we make use of the processor" bit. This is used along with the half bit todetermine exactly what processor. It breaks down like this:

Half bit 0 / Processor bit 0 A

Half bit 0 / Processor bit 1 B

Half bit 1 / Processor bit 0 C

Half bit 1 / Processor bit 1 - D

Then, like the original calculation, we use the Port bit to determine the 0/A port or the 1/B port.


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World Wide Name CLARiiON Target

y CX600 example:

5 0 0 6 0 1 6 0 0 0 6 0 0 1 B 2 50101 0000 0000 0110 0000 0001 0110 0000 0000

00000 0110 0000 0000 0001 1011 0010 0101

EMC Company ID 24 bits Port CLARiiON seed 32 bits

0000

CLARiiON - CX600

WWN seed - 00:60:01:b2

Resulting WWNN therefore is 50:06:01:60:80:60:01:b2

Resulting WWPNs therefore are:

Storage Processor A

Port 0 - 50:06:01:60:00:60:01:b2

Port 1 - 50:06:01:61:00:60:01:b2

Port 2 - 50:06:01:62:00:60:01:b2

Port 3 - 50:06:01:63:00:60:01:b2

Note : On the FC4500, we have the only real exception as the FC ports are in fact connected to a

hub and share their WWPN. To get around this, only one port from each SP would be connected

to the Fabric. Two ports existed per SP to allow for a dual cluster direct attach.


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Frames routing

Source

TargetFabric

Physical cable connected

HBA WWN:

10000000C920DC40

FA WWN:

50060482E8912B90


ISL

Sw 01

Sw 02

Port 07

Port 05

y When N_Ports areconnected to F_Ports,the Fabric Loginbegins, associatingphysical address andWorld Wide Name

When N_Ports are connected to F_Ports, the Fabric Login begins, associating physical addresses

and World Wide Names.


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Frames routing (contd)

Source

TargetFabric


HBA WWN:

10000000C920DC40

FA WWN:

50060482E8912B90


ISL

Sw 01

Sw 02

Port 07

Port 05

yThe WWN andPhysical Address

association is done bythe switch and isstored using internaltables

y So the frames arerouted using theirPhysical Address

WWN ->Switch/Port/AL_PA

10000000C920DC40 ->020500

50060482E8912B90 ->010700

The WWN and Physical Address association is done by the switch and is stored using internal

tables.

The frames are routed using their Physical Address, same as happens in an FC-AL environment,

using just the AL_PA.


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Frames routing (contd)

Source

TargetFabric


HBA WWN:

10000000C920DC40

FA WWN:

50060482E8912B90


ISL

Sw 01

Sw 02

Port 07

Port 05

y Any changes in theswitchs ports willnot impact futureframe routing, oncethe internal tablesare updated

WWN ->Switch/Port/AL_PA

10000000C920DC40 ->02060050060482E8912B90 ->010700

Port 06

When nodes generate frames, they are routed by their addresses, not their WWNs. However,

tables can be built which can associate WWNs to the destination addresses. A World Wide

Name is a 64 bit value (16 characters).


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Fibre Channel Logins

N_Port

1

N_Port

1F_PortF_Port F_PortF_Port N_Port

2

N_Port

2

Fabric

Process aProcess a

Process bProcess b

Process cProcess c

Process xProcess x

Process yProcess y

Process zProcess z

Fabric Login Fabric Login

Accept AcceptPort Login

Accept

Process Login

Accept

There are three types of login supported in Fibre Channel: Fabric, Port and Process. All nodeports must attempt to log in with the Fabric. This is typically done right after the link or the

Loop has been initialized. It consists of the node port transmitting a Fabric Login (FLOGI)frame to the well-known Fabric address hex'FFFFFE'. The normal response is an Accept (ACC)frame from the Fabric back to the node port. Fabric Login accomplishes the following things:

y It determines the presence or absence of a Fabric.

y If a Fabric is present, it provides a specific set of operating characteristics associated withthe entire Fabric, including which Classes of service are supported.

y If a Fabric is present, it will optionally assign or will confirm the native N_Port Identifier ofthe N_Port that initiated the Login.

y If a Fabric is present, it initializes the buffer-to-buffer credit.

Before a node port can communicate with another node port, it must first perform N_Port Loginwith that node port. Similar to Fabric Login, the N_Port transmits a PLOGI frame to thedestination node port. Again, the normal response is an ACC frame. Port Login accomplishesthe following things:

y It provides a specific set of operating characteristics associated with the destination N_Port,including Class of service.

y With Class 3 services, buffer-to-buffer credit is initialized.

PRLI is an acronym for Process login. Process logins establish sessions between relatedprocesses on a source and target N_Port. The processes are typically FC-4 layer applications.


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Fabric Login

yThe Fabric Login (FLOGI) is used by an N_Port todetermine the presence of a Fabric, then exchangeservice parameters.

yThe N_Port performs a login to address FFFFFE (F_PortServer) using a source address of 000000.

yThe Fabric Login service returns a frame which assignsan address to the port (24 bits)

When a Fibre Channel device is attached to a Fabric, it will begin a Fabric login (FLOGI).

FLOGI is an extended link service command that sets up a session between two participants.

With FLOGI, a session is created between an N_Port or NL_Port and a F_Port or FL_Port. An

N_Port will send a FLOGI frame that contains its Node Name, its N_Port Name, and service

parameters to address 0xFFFFFE.


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FLOGI

Port Address RequestPort Address Request

Registration Request Registration Request

Directory Server

(NameServer)

(xFF FF FC)

Port Identifier (SID)

Port Name (WWN)

Classes of Service (Class 3)

FC-4 Types Supported (SCSI)

Port Type (N_Port)

Zoning Information

HBA

N_Port

HBA

N_Port

FA

N_Port

FA

N_Port

Fabric Server

(xFF FF FE)

Query Request Query Request

When the N_Port logs in, it uses a 24-bit port address of 0x000000. Because of this, the Fabric is

allowed to assign the appropriate port address to that device, based on the Domain-Area-Port

address format. The newly assigned address is contained in the ACC response frame.


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Fabric Login in Loop Environment

y A public loop port first opens the destination AL_PA 0x00before issuing the FLOGI

y NL_Port logs in a similar process, except that the last 8bits of the Physical Address is used

y Before an NL_Port logs in it will go through the LIP, thisensures that the switch assigned AL_PA does not conflictwith any previously selected AL_PAs on the loop

An N_Port first opens the destination AL_PA 0x00 before issuing the FLOGI request. The

switch accepts the login and returns an accept (ACC) frame to the sender. If some of the service

parameters requested by the N_Port are not supported, the switch will set the appropriate bits in

the ACC frame to indicate this.

When the NL_Port logs in a similar process starts, except that the least significant byte is used to

assign the AL_PA and the upper two bytes constitute a Fabric loop identifier. Before an

NL_Port logs in, it will go through the LIP on the loop, which is started by the FL_Port, and

from this process it has already derived an AL_PA. The switch then decides if it will accept this

AL_PA for this device or not. If not, a new AL_PA is assigned to the NL_Port, which then

causes the start of another LIP. This ensures that the switch assigned AL_PA does not conflict

with any previously selected AL_PAs on the loop.


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Fabric Login Name and Directory Service

y Information is then registered with the Directory Service(FFFFFC) such as :

Port Identifier (ID) = S_ID

Port Name(PN) = WWN of the N_Port

Classes of Service (CS) = Class 3 currently

FC-4 Types Supported (FT) = SCSI-3

Port Type (PT) = N_Port

y Once a port has logged in, it can query the Name Servicedatabase for information about all other logged in ports

After the node gets its Fabric address from FLOGI, it needs to register with the SNS with port

login (PLOGI) on address 0xFFFFFC. The device may register values for all or just some

database objects, but the most useful are:

y Port Identifier (ID) = S_ID

y Port Name(PN) = WWN of the N_Port

y Classes of Service (CS) = Class 3 currently

y FC-4 Types Supported (FT) = SCSI-3

y Port Type (PT) = N_Port

Once a port has logged in, it can query the Name Service database for information about all

other logged in ports.


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Port Login (PLOGI)

y Happens when an N_Port logs in to another N_Port (HBAlogs in to an FA for instance). At this moment, a table iscreated speeding up data transfer between the nodes

y Port logins exchange information such as:

host address (SID)

frame size (receive buffer size)

flow control & version information (TOVs)

port name (WWPN)

y Some platforms require re-login when there is a long idleperiod (HP-UX for instance)

y Service parameters are exchanged between nodesbefore any upper level commands can be issued

When an N_Port logs in to another N_Port, a table can be built which will keep track of the

WWN of the logged in port along with its Fibre Channel address. For example, when the NT

and SUNs login to the Symmetrix, a table is created. This speeds data transfers and node-to-

node communications.

Some Host types (for example, HP-UX) may not maintain a connection while idle and would

need to re-login.

Port login is used to establish a session between two nodes, swapping service parameters and

making themselves known to each other.

Port logins exchange information such as:

y

host address (SID)y frame size (receive buffer size)

y flow control & version information (TOVs)

yport name (WWPN)


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Process Login (PRLI)

y Process Login sets up the environment between nodeports and is done by the FC-4 layer

y At this level, each Fibre Exchange is composed of SCSItasks (individual or grouped commands)

y Some SCSI commands:

FCP_CMND

FCP_XFER_RDY

FCP_DATA

FCP_RSP

Process login is used to set up the environment between related processes on node ports.

The Fibre Channel Protocol for SCSI-3 standard specifies that each SCSI task corresponds toFibre Channel exchange. A Fibre Channel exchange consists of a single SCSI command or a

group of linked SCSI commands. The FCP mapping of SCSI-3 to Fibre Channel defines four

information sets that are transferred between SCSI initiator and target. The information sets are

modeled after the SCSI-3 architecture defined protocols services.

y FCP_CMND - Corresponds to Send SCSI Command protocol service

y FCP_XFER_RDY Transports the offset and request byte count objects of the Send Data-In

and Receive Data-Out protocol services

y FCP_DATA - Transports the data object of the Send Data-In and Receive Data-Out protocol

services

y FCP_RSP corresponds to the Send Command Complete protocol service


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FC-3

y FC-3 was put into FibreChannel as aplaceholder

y In concept FC-4 wouldpass requests to FC-3that would perform thedesired service andthen pass onto FC-2





FC-3 was put into Fibre Channel as a placeholder. In concept, FC-4 would pass requests to FC-3

that would perform the desired service and then pass onto FC-2.

Some of the things that have been identified as probably fitting into FC-3 are:

y Data Striping

y Multipathing

y Mirroring

y RAID

y Data encryption

y Data compression

y Data Translation


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FC-4

yThe FC-4 level of FibreChannel is designed tohand off to anotherprotocol such as SCSI

y Fundamentally, thecommands at FC-4 forSCSI allow SCSIinitiator and target to

communicate overFibre ChannelFibre Channel Level 1 (FC1)Fibre Channel Level 1 (FC1)





The FC-4 level consists of several standards documents describing how different upper-level

protocols (ULPs) use the transport services provided by levels FC-2, FC-1 and FC-0. The

purpose of an FC-4 protocol mapping is to make a logical connection between the ULPs and

Fibre Channel's transport facilities.


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ULP - Upper Layer Protocol

y ULP not actually partof Fibre Channel

y Some examples ofULPs are:

Small Computer SystemInterface (SCSI)

Intelligent PeripheralInterface (IPI)

High PerformanceParallel Interface (HiPPI)

Bus and Tag (FIPS) orESCON

IEEE 802.2 Logical LinkControl (LLC)





ULPULP


ULP (Upper level Protocol) is not actually part of Fibre Channel.

Some examples of ULPs are:y Small Computer System Interface (SCSI)

y Intelligent Peripheral Interface (IPI)

y High Performance Parallel Interface (HiPPI)

y Bus and Tag (FIPS) or ESCON

y IEEE 802.2 Logical Link Control (LLC)


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Lesson 3 SAN Concepts


yDescribe Direct Connect, Arbitrated Loop and SwitchedFabric topology

y Understand the differences between Hub and Switch

y Know Fibre Channel Port types

y Identify Departmental Switches and Enterprise Directorsmodels and features

y Explain different SAN usages (VSAN, Routed andVirtualization)



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Physical and Logical Topologies

yThe Fibre Channel environment consists of physicaltopology and logical topology

Fibre Channel

Switch

Windows

Server

Sun

Server

Storage

Physical

Topology

Logical

Topology

Physical

Topology

The Fibre Channel environment consists of a physical topology and a logical topology. The

physical topology describes the physical interconnects among devices (servers, storage, and

switch in the EMC-specific environment). The logical topology describes the logical paths

established between the operating system device names and their associated storage ports and

volumes.

Logical topologies in the EMC/Fibre Channel switch environment can generally be described in

terms offan-in(into the EMC storage array) and fan-out (out ofthe EMC storage array).


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Direct Connect Topology

yThe ANSI Fibre Channel Standards define threetopologies

Direct Connect

Arbitrated loop (FC-AL)

Switched Fabric (FC-SW)

y Direct Connect is the simplest topology, where twodevices are directly connected to each other

The ANSI Fibre Channel Standards define three topologies: Direct Connect, Arbitrated loop

(FC-AL), and Switched Fabric (FC-SW).

This slide shows a Fibre Channel topology where two devices are directly connected to each

other.

EMC specifies a 2 node FC-AL connection called Direct Connect. This Topology is the same as

the standard Arbitrated Loop except that there are two nodes in the Loop and the FC-AL Hub is

not used.


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Arbitrated Loop (FC-AL) Topology

y All devices are in a loop or ring over attachment pointscalled L_Ports (loop ports)

y FC-AL is a low-cost connectivity solution because it doesnot require switches

Fibre Channel

Hub

y Efficiency andconnectivity isenhanced byincorporating oneor more hubs intothe loop

Arbitrated Loop (FC-AL) is a daisy-chainconnecting up to 126 devices in a loop configurationover attachment points called L_Ports(loop ports). FC-AL is a low-cost connectivity solutionbecause it does not require switches.

FC-AL is a good choice for small to medium-sized configurations, and provides a growth path

by allowing connection of a loop to a switched Fabric.

Efficiency and connectivity is enhanced by incorporating one or more hubs into the loop.

Routing traffic through a hub on each leg of a loop eliminates the loss of the entire loop, as

happens in a hubless loop.


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Switched Fabric (FC-SW) Topology

y Switched Fabric is a Fibre Channel topology where manydevices connect with each other via Fibre Channel

switches

y Frames are routed between source and destination bythe Fabric

Fibre Channel

Switch

yThis topologyallow the mostnumber of

connectivity witha theoretical 16million devicesper Fabric

Switched Fabric (FC-SW) is one or more dynamic Fibre Channel switches connecting multiple

devices. FC-SW involves a switching device (the Fabric) interconnecting two or more nodes.

Rather than traveling around an entire loop, frames are routed between source and destination by

the Fabric.


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Arbitrated Loop Switches

y Fibre Channel hubs are used with Fibre ChannelArbitrated Loop (FC-AL) to increase server and storageconnectivity

y Using a hub, multiple servers can access multiple storagedevices

y EMC Symmetrix storage systems are qualified with hubsin limited configurations with:HP-UX

Sun Solaris

Windows NT, Windows 2000, Windows2003

Siemens servers

Fibre Channel hubs are used with Fibre Channel Arbitrated Loop (FC-AL) to increase server

and storage connectivity. Using a hub, multiple servers can access multiple storage devices.

A Hub can only have one Full Duplex connection between port pairs at any one time. Although

every port is capable of full speed operation, only one pair of ports can be active at any one

time. This is due to the fact that only two nodes in an FC-AL environment can be active at any

one time, and they must be communicating with each other (pair).

EMC Symmetrix storage systems are qualified with hubs in limited configurations with HP-UX,

Sun Solaris, Windows NT, Windows 2000, Windows 2003, and Siemens servers.


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Switches

y A Fibre Channel switch is a device that routes databetween host bus adapters and fibre adapters on storagesystems

y A Fabric is a single switch or multiple switches thatinterconnect various N_Ports, and is capable of routingframes by using only the D_ID information in a FibreChannel frame header

y Larger Fabric will be built by connecting

multiple switches through E_Ports

Switched Fabrics offer strong advantages over hubs, in both performance and manageability.

For example, a hub can have only one full-duplex connection between port pairs at one time.

Although every port in a 10-port hub is capable of full-speed operation, only one pair of ports

can be active at any one time. A switched Fabric, however, can have every port pair running full

duplex simultaneously at 200 MB/s. In a switched topology, aggregate bandwidth of 200 MB/s

times the Fabric port count is possible.

The aggregate bandwidth of a hub is fixed, but the aggregate bandwidth of a Fabric scales as

additional port pairs are added. This scaling capability is an important management feature,

because it allows the administrator of the enterprise storage network to reallocate the bandwidth

of the network among N_Ports without moving cables and reconfiguring the environment.

A second management benefit of switched Fabrics over hubs is a Fabric-based service called thename server, which maintains a table of all logged-in devices.

Used by the N_Ports for device discovery, the table is maintained by the Name Server during

Fabric reconfigurations.


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Fibre Channel SAN Switches and Directors

y Directors are considered to be more highly available thanswitches

Switches are Directors are

y Lower number of ports

y Availability features

y High performance

y Web-based managementfeatures

y Highest port count

y Highest availability

y Highest performance

y Web-based and/orconsole-basedmanagement features

In a SAN, implementation is necessary to select the director, switch or hybrid technology

solution.

The switch/director decision is often financial. Technically, directors are preferable to switches.

If we consider the differences between them:

y Directors are easier to manage because the relationship between ports is equal and, therefore,

it does not need to be considered in performance planning. A single high-availability Fabric

is possible using directors, though switches require two Fabrics.

y Directors have scaled failure localization. This means the GBIC, power supply, etc. can each

be replaced without bringing down the entire device, limiting risk of catastrophic failure.

y Switches offer some localization, at the GBIC or power supply, but in general, a physical

failure results in whole device replacement.

Directors are considered to be more highly available than switches. To be fully redundant, there

is a requirement for multiple connections to more than one network, with complete routes to all

devices throughout those networks. This improves resiliency of the Fabric, allowing the SAN to

maintain its functionality in the even of failures. Because fault isolation in a director is at a more

granular component level and the components are already dual redundant, directors have the

least adverse impact on availability.


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EMC Connectrix Products

SERVICE LEVEL

COST

ED-140M

DS-24M2

MDS-9120

MDS-9140

DS-8B3

DS-16B3

ED-24000B

MDS-9509

Connectrix Directors

y Redundant everythingprovides optimal

serviceability and highest availabilityy Data-center deployment

y Maximum scalability

y Large Fabrics

Connectrix Switchesy Redundant fans and power supplies

y High availability through redundantdeployment

y Departmental and data-centerdeployment

DS-32M2

ED-64M

MP-1620M

MDS-9506MDS-9216i/A

AP-7420B

MP-2640M

DS-4100B

Only EMC offers a complete range of SAN productsfrom Connectrix directors for data-center

deployments to Connectrix switches for data-center and departmental deployment.

The Connectrix Family gives customers:

y The widest range of SAN service levels

y More choice

y Additional Fibre Channel functionality

y A pathway to IP SANs

y An additional platform for future network-hosted applications


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Types of Fibre Channel Port

TYPE DESCRIPTION

N_Port Node port, a port at the end of a point-to-point link

NL_PortNode Loop port, a port which supports the arbitrated looptopology

F_PortFabric port, the access point of the Fabric which connectsto a N_Port

FL_PortFabric Loop port, a Fabric port which connects to aNL_Port

E_Port Expansion port on a switch. Links multiple switches

G_PortGeneral port, a Connectix McDATA switch port with theability to function as either an F_Port or an E_port

U_Port Universal port, Connectrix B series equivalent to a G_Port

In an environment using Host Bus Adapters and Symmetrix FC Directors, ports are configured

as either N-Ports or NL-Ports:

yN_Port - Node port, a port at the end of a point-to-point link

yNL_Port - Node Loop port, a port which supports the arbitrated loop topology

Fibre Channel Switch ports are also configured for specific applications:

y F_Port - Fabric port, the access point of the Fabric which connects to a N_Port

y FL_Port - Fabric Loop port, a Fabric port which connects to a NL_Port

y E_Port - Expansion port on a switch. Links multiple switches

yG_Port - General port, a Connectix McDATA switch port with the ability to function aseither an F_Port or an E_port

y U_Port - Universal port, Connectrix B series equivalent to a G_Port


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Fabric

N_PortN_Port

N_PortN_Port

N_PortN_Port

N_PortN_Port

F_PortF_Port

F_PortF_Port

F_PortF_Port

G_PortG_Port

E_PortE_Port

F_PortF_Port

E_PortE_Port

Fabric

ISL

A Fabric is a switch or a group of switches linked together.

When looking at the graphic above you will notice that the cloud of the Fabric is actually twoseparate switches attached together via an ISL (Interswitch Link). Attached to the Fabric are

several N ports which represent end port devices such as HBAs and Storage ports.

The term Enterprise Director indicates a switch that has all major components redundant at the

hardware level. If any major part fails, the switch will automatically fail over, maintaining

operation during the failure. The Enterprise directors are commonly used as core switches in a

core edge topology.

A Departmental switch has less redundancy and is meant for smaller workgroups. With the lack

of redundancy, the departmental switches are commonly used as edge switches for core edge

designs with PowerPath in place for redundancy in case of a switch failure.


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Zoning

y Partitions a Fibre Channel switched Fabric into subsetsof logical devices

y Zones contain a set of members that are permitted toaccess each other

y A member can be identified by its Source ID (SID), itsWorld Wide Name (WWN), or a combination of both

Zoning is used to partition a Fibre Channel switched Fabric into subsets of logical devices. Each

zone contains a set of members that are permitted to access each other. Members can be switch

ports, HBAs, or storage ports. When zoning is enabled, members in the same zone can see and

communicate with each other, but members in separate zones cannot. Ports and devices

distributed across multiple switches in a Fabric may be grouped into the same zone.

A zone member can be identified by its Source ID (SID), its World Wide Name (WWN), or a

combination of both. Zones can be created using each of these forms of member identification.

Thus, there are essentially three types of zoning: hard zoning, soft zoning, and mixed zoning.


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What is Zoning?

10000000C920C4E4

10000000C920C321

200000E069000CFE

200000E0690014B8

200000E06900156D

50060482B8912B9E

50060482B8912B8E

50060482B8912B8F

50060482B8912B9F

500601684003491C

A Switched Fabric can be subdivided into a number of zones:

y

A single zone typically includes two or more portsy Zones can be created by

Switch Port Number (Static)

HBA WWN (Flexible)

Custom Nickname/Alias

EMC recommends that zones include only one HBA (Single HBA zoning), however an HBA

may belong to multiple zones. Zones may include one or more EMC Symmetrix FA ports. FAs

may belong to multiple zones.


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Single Init iator Zoning

y Always put ONLY one HBA in a zone with Storage ports

yEach HBA port can only talkto Storage ports in thesame zone

y HBAs & Storage Ports may be members of more thanone zone

y HBA ports are isolated from each other to avoid potentialproblems associated with the SCSI discovery process

y Decreases the impact of a Registered State Change in aFabric by reducing the amount of nodes that must loginagain

Under single-HBA zoning, each HBA is configured with its own zone. The members of the zoneconsist of the HBA and one or more storage ports, such as a Symmetrix Fibre Adapter (FA) port,

with the volumes that the HBA will use.

This zoning practice provides a fast, efficient, and reliable means of controlling the HBAdiscovery/login process. Without zoning, the HBA will attempt to log in to all ports on theFabric during discovery and during the HBAs response to a state change notification. Withsingle-HBA zoning, the time and Fibre Channel bandwidth required to process discovery andthe state change notification are minimized.

Two VERY good reasons for Single HBA Zoning:

y Cuts down on the reset time for any change made in the state of the Fabric.

y Only the nodes within the same zone will be forced to log back into the Fabric after a RSCN(Registered State Change Notification)

When a nodes state has changed in a Fabric (i.e. cable moved to another port), it will have toperform the Fabric Login process again before resuming normal communication with the othernodes it is zoned with. If there is only one SCSI Initiator in the zone (HBA), then the amount ofdisrupted communication is reduced.

If you had a zone with two HBAs and one of them had a state change, then BOTH would beforced to log in again, causing disruption to the other HBA that did not have any change in itsFabric state. Performance can be severely impacted by this.


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Hard and Soft Zoning

Host

WWPN = 10:00:00:00:C9:20:DC:40

WWPN = 10:00:00:60:69:40:8E:41

Domain ID = 21

Port = 1

FC

Switch

FC

SwitchStorage

Fabric

WWPN = 50:06:04:82:E8:91:2B:9E

WWPN = 10:00:00:60:69:40:DD:A1

Domain ID = 25

Port = 3

In general, zoning can be divided into two categories:

y

Port zoningy WWN zoning


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WWN Zoning

Host

WWPN = 10:00:00:00:C9:20:DC:40

WWPN = 10:00:00:60:69:40:8E:41

Domain ID = 21

Port = 1

FC

Switch

FC

SwitchStorage

Fabric

WWPN = 50:06:04:82:E8:91:2B:9E

WWPN = 10:00:00:60:69:40:DD:A1

Domain ID = 25

Port = 3

WWN Zone 1 =10:00:00:00:C9:20:DC:40; 50:06:04:82:E8:91:2B:9E

WWN zoning creates zone sets using the WWNs of the attached nodes. This allows you to move

nodes from one switch port to another without having to change the zone configuration. The

zone set becomes independent of individual switch ports.


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Port Zoning

Host

WWPN = 10:00:00:00:C9:20:DC:40

WWPN = 10:00:00:60:69:40:8E:41

Domain ID = 21

Port = 1

FC

Switch

FC

SwitchStorage

Fabric

WWPN = 50:06:04:82:E8:91:2B:9E

WWPN = 10:00:00:60:69:40:DD:A1

Domain ID = 25

Port = 3

Port Zone 1 =21,1; 25,3

Port zoning, based on physical topology, uses the domain ID and port number of the switch (in

the format domainID:port number), not the port WWN of the attached device to determine the

zone set. This method allows you to change the HBA without changing any zoning information.

However, it does not give you the flexibility to physically move attached nodes between switch

ports without having to redefine the port number in the zone set.


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Zoning Components

Member #1

Member #2

Member #3

Member #4

Zone #1

Zone #2

Active Zone Set

Old Zone Set #1

Old Zone Set #2

Member #5 Zone #3

Members are attached adapters which can be included in a zone. They include HBAs and

Storage Fibre adapter ports. A Storage Fibre adapter is a front end port on a storage system.

Examples include Symmetrix FA ports, CLARiiON SP ports and Compaq adapter ports.

A zone contains a set of members that can access each other. A member can be a Storage Fibre

adapter or a Host Bus Adapter (HBA) that is logged into a switch device. Devices spread

throughout multiple switches in a multiswitch Fabric may be grouped into the same zone.

Multiple zones can be assigned membership in one zone set. Zones are built and then included

into a specific zone set based on the customers requirement to activate multiple zones

simultaneously. Zone sets are then activated to simultaneously activate the zones in the set.

Zoning a hosts HBA with a Symmetrix or CLARiiON Storage Fibre adapter port allows

communication between those members. Volumes visible on that storage port will now beavailable to the host. Members of a zone can see each other; members in different zones cannot.

A zone set is a group of zones that you can activate or deactivate as a single entity in either a

single unit or a multi-unit Fabric. Only one zone set can be active at one time per Fabric.

The active zone set is a single zone set that is currently enabled. When a zone set is active, all

zones that are members of that zone set are active.


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VSAN

y VSANs are logical SANs providing isolation amongphysically connected devices.

VSANs are logical SANs over a common physical Fabric allowing logical segments in the

network. Multiple independent SANs over a common physical infrastructure provide isolation

among devices that are physically connected.


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Distance Extension Options

y WDM

Metro region (100s km)

Shared infrastructure for many applications

High bandwidth needs

y SONET

Long-distance solutions (1000s km)

Smaller sites feeding into WDM

y IP

Native IP for simplicity

Bridged IP when WDM and SONET not available

Reuse part of existing infrastructure

WDM

y

Metro region (100s km)y Shared infrastructure for many applications

y High bandwidth needs

y Limitation: Availability of dark fiber; Can be high cost

SONET

y Long-distance solutions (1000s km)

y Smaller sites feeding into WDM

y Limitation: Cost varies (IP can be less expensive); Can be difficult to provision

IP

yNative IP for simplicity

y Bridged IP when WDM and SONET not available

y Reuse part of existing infrastructure

y Limitation: Need a well-designed network; Limited interoperability between IP bridges


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SAN Routing - Solution

y SAN Routing

yA study group dedicated for the development of thestandards

y Benefits:

Hierarchical network

Local Fabrics can be kept small

Only the shared resources can be shared (routed) between Fabrics

SAN Routing is a new technology development of the FC protocol.

A study group within T11 was formed that is dedicated for the development of the standards toaccommodate the solution.


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SAN Virtualization - Solution

y SAN Virtualization

yUses the storage network to redirect IOs on the fly

y Benefits:

Free space can be utilized from any/all arrays in the network

Data migration becomes a real time activity

SAN virtualization uses the storage network to redirect IOs on the fly.


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FCIP

yTCP/IP based tunneling/encapsulatingprotocol for connecting/extending FibreChannel SANs

y More IP content, little Fibre Channelcontent

FCIP is a TCP/IP based tunneling/encapsulating protocol for connecting/extending Fibre

Channel SANs. It contains more IP content, little Fibre Channel content.


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iFCP

y Gateway to gateway protocol for FC over IP

y Mapping natively in IP across Fibre Channeland IP

y An IP-based tunneling protocol forinterconnecting Fibre Channel devicestogether in place of Fibre Channel switches

y More Fibre Channel content; when iFCPcreates the IP packets, it inserts informationthat is readable by network devices androutable within the IP network.

y IFCP wraps Fibre Channel data in IP packetsbut maps IP addresses to individual FibreChannel devices

iFCP is a gateway to gateway protocol for FC over IP, mapping natively in IP across Fibre

Channel and IP. It is an IP-based tunneling protocol for interconnecting Fibre Channel devices

together in place of Fibre Channel switches. It has more Fibre Channel content.

When iFCP creates the IP packets, it inserts information that is readable by network devices and

routable within the IP network. IFCP wraps Fibre Channel data in IP packets but maps IP

addresses to individual Fibre Channel devices.


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Block Storage over IP Solutions - Native

y All Ethernet (No Fibre Channel)

y iSCSI Protocol

y Ethernet Switches & Routers

LAN LAN

NativeiSCSI allows for all communications using Ethernet. Initiators may be directly attachedto iSCSI Targets or may be connected using standard Ethernet routers and switches.


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Block Storage over IP Solutions - Bridging

y Servers Ethernet Attached

y Storage FC Attached (SAN or DAS)

y iSCSI Protocol

LAN SAN

iSCSI SAN Switch

iSCSI Storage Por t

Bridgingarchitectures allow for the Initiators to exist in an Ethernet environment while thestorage remains in a Fibre Channel SAN.


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Block Storage over IP Solutions - Extension

y Servers & Storage SAN Attached

y FCIP or iFCP Protocol

y SRDF

SAN SAN

WAN

FCIP Routers or iFCP Switches

Extension architectures are most often used to provide connectivity across large distances.Either FCIP or iFCP bring the long distance benefits of IP to Fibre Channel.


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Course Summary

Key points covered in this course:

yFibre Channel Architecture

y Fibre Channel Layers

y Fibre Channel Topologies

y SAN concepts

These are the key points covered in this training. Please take a moment to review them.

This concludes the training. In order to receive credit for this course, please proceed to theCourse Completion slide to update your transcript and access the Assessment.

Documents

76359902 Introduction to Fiber Channel