Dell PowerVault MD3220i manual

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Dell PowerVault MD3200 and
MD3220 Storage Arrays
Deployment Guide
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Notes, Cautions, and Warnings
NOTE: A NOTE indicates important information that helps you make better use of
your computer.
CAUTION: A CAUTION indicates potential damage to hardware or loss of data if
instructions are not followed.
WARNING: A WARNING indicates a potential for property damage, personal
injury, or death.
__________________
© 2013 Dell Inc.
Trademarks used in this text: Dell™, the DELL logo, PowerEdge™, PowerVault™, and
OpenManage™ are trademarks of Dell Inc. Intel® is a registered trademarks of Intel Corporation in
the U.S. and other countries. Microsoft®, Windows®, Windows Server®, MS-DOS®, and Internet
Explorer® are either trademarks or registered trademarks of Microsoft Corporation in the United
States and/or other countries. Red Hat® and Red Hat Enterprise Linux® are registered trademarks of
Red Hat, Inc. in the United States and other countries. SUSE® is a registered trademark of Novell,
Inc. in the United States and other countries.
2013 - 07 Rev. A02
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Contents 3
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . 7
System Requirements . . . . . . . . . . . . . . . . . . . 7
Management Station Requirements . . . . . . . . . 7
Introduction to Storage Arrays . . . . . . . . . . . . . . 8
2 Hardware Installation . . . . . . . . . . . . . . . 11
Planning the Storage Configuration. . . . . . . . . . . 11
Connecting the Storage Array . . . . . . . . . . . . . . 12
Cabling the Storage Array . . . . . . . . . . . . . . . . 12
Redundant and Non-Redundant Configurations . . 13
Single Controller Configurations . . . . . . . . . . 13
Dual Controller Configurations . . . . . . . . . . . 16
Cabling PowerVault MD1200 Series Expansion
Enclosures . . . . . . . . . . . . . . . . . . . . . . . . 22
Expanding With Previously Configured
PowerVault MD1200 Series Expansion
Enclosures . . . . . . . . . . . . . . . . . . . . . 22
Expanding With New PowerVault MD1200
Series Expansion Enclosures. . . . . . . . . . . . 24
3 Installing PowerVault MD Storage
Software . . . . . . . . . . . . . . . . . . . . . . . . . 27
Graphical Installation (Recommended) . . . . . . 28
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4 Contents
Console Installation. . . . . . . . . . . . . . . . . 29
Silent Installation . . . . . . . . . . . . . . . . . . 29
Upgrading PowerVault MD Storage Software . . . . . 30
4 Post Installation Tasks. . . . . . . . . . . . . . 31
Before You Begin. . . . . . . . . . . . . . . . . . . . . 31
iSCSI Configuration Worksheet . . . . . . . . . . . . . 32
IPv4 Settings—Worksheet . . . . . . . . . . . . . 33
IPv6 Settings—Worksheet . . . . . . . . . . . . . 34
Configuring iSCSI on Your Storage Array . . . . . . . . 35
Automatic Configuration Using the Modular
Disk Configuration Utility . . . . . . . . . . . . . . 36
Post Connection Establishment Steps. . . . . . . . . . 39
Guidelines For Configuring Your Network For iSCSI . . 40
Microsoft Windows Host Setup . . . . . . . . . . . . . 40
Using A DHCP server . . . . . . . . . . . . . . . . 40
Using static IP addressing . . . . . . . . . . . . . 40
Using A DNS server. . . . . . . . . . . . . . . . . 41
Using A WINS Server . . . . . . . . . . . . . . . . 41
Linux Host Setup . . . . . . . . . . . . . . . . . . . . . 42
Using DHCP . . . . . . . . . . . . . . . . . . . . . 42
Using A Static IP Address . . . . . . . . . . . . . 42
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Contents 5
5 Uninstalling PowerVault MD
Storage Software . . . . . . . . . . . . . . . . . . 45
Uninstalling MD Storage Software From Windows . . 45
Uninstalling MD Storage Software From Linux. . . . . 46
6 Getting Help. . . . . . . . . . . . . . . . . . . . . . . 47
Locating Your System Service Tag . . . . . . . . . . . 47
Contacting Dell . . . . . . . . . . . . . . . . . . . . . 47
Documentation Feedback . . . . . . . . . . . . . . . . 48
A Appendix—Load Balancing. . . . . . . . . . . 49
Windows Load Balance Policy . . . . . . . . . . . . . 49
Round Robin With Subset . . . . . . . . . . . . . 49
Least Queue Depth With Subset . . . . . . . . . . 50
Changing Load Balance Policies in
Windows Sever 2008 . . . . . . . . . . . . . . . . 50
Setting Load Balance Policies in Linux. . . . . . . 51
B Appendix—Manual Configuration
of iSCSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Step 1: Discover the Storage Array
(Out-of-band Management Only) . . . . . . . . . . . . 54
Default Management IPv4 Port Settings . . . . . . 54
Automatic Storage Array Discovery . . . . . . . . 55
Manual Storage Array Discovery . . . . . . . . . 56
Setting Up the Array . . . . . . . . . . . . . . . . 56
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6 Contents
Step 2: Configure the iSCSI Ports on the
Storage Array. . . . . . . . . . . . . . . . . . . . . . . 57
Step 3: Perform Target Discovery From
the iSCSI Initiator . . . . . . . . . . . . . . . . . . . . 59
Step 4: Configure Host Access. . . . . . . . . . . . . . 61
Understanding CHAP Authentication . . . . . . . . . . 62
What is CHAP? . . . . . . . . . . . . . . . . . . . 62
Target CHAP. . . . . . . . . . . . . . . . . . . . . 62
Mutual CHAP . . . . . . . . . . . . . . . . . . . . 62
CHAP Definitions . . . . . . . . . . . . . . . . . . 63
Step 5: Configure CHAP Authentication on the
Storage Array (Optional) . . . . . . . . . . . . . . . . . 63
Configuring Target CHAP Authentication on
the Storage Array . . . . . . . . . . . . . . . . . . 63
Configuring Mutual CHAP Authentication on
the Storage Array . . . . . . . . . . . . . . . . . . 64
Step 6: Configure CHAP Authentication on the
Host Server (Optional) . . . . . . . . . . . . . . . . . . 65
Step 7: Connect to the Target Storage Array From
the Host Server. . . . . . . . . . . . . . . . . . . . . . 69
Step 8: (Optional) Set Up In-Band Management. . . . . 72
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Introduction 7
1
Introduction
This guide provides information about deploying Dell PowerVault MD3200
and Dell PowerVault MD3220 storage arrays. The deployment process
includes:
• Hardware installation
• Modular Disk Storage Manager (MDSM) software installation
• Initial system configuration
Other information includes system requirements, storage array organization,
and utilities.
NOTE: For more information on product documentation, see
dell.com/support/manuals.
MDSM enables an administrator to configure and monitor storage arrays for
optimum usability. The version of MDSM included on the PowerVault MD
series resource media can be used to manage both the PowerVault MD3200
series and the earlier PowerVault MD series storage arrays. MDSM is
compatible with both Microsoft Windows and Linux operating systems.
System Requirements
Before installing and configuring the PowerVault MD3200 series hardware
and software, ensure that a supported operating system is installed and the
minimum system requirements are met. For more information, see the
Support Matrix at dell.com/support/manuals.
Management Station Requirements
A management station uses MDSM to configure and manage storage arrays
across the network. A management station must meet the following
minimum system requirements:
• Intel Pentium or an equivalent processor (1333 MHz or faster) with 512
MB RAM (1024 MB recommended).
• 1 GB disk space.
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8 Introduction
• Display resolution of 1024x768 with 16 million colors (1280x1024 32-bit
recommended).
• Microsoft Windows, Red Hat Enterprise Linux, or SUSE Linux Enterprise
Server.
NOTE: Supported operating systems include both native and guest operating
systems.
NOTE: Supported hypervisors include Microsoft Hyper-V, Citrix XenServer,
and VMware ESX and ESXi. For information about the supported versions, see
the Support Matrix at dell.com/support/manuals.
• Administrator or equivalent permissions.
Introduction to Storage Arrays
An enclosure containing physical disks accessed through RAID controller
modules is called a storage array. A storage array includes various hardware
components, such as physical disks, RAID controller modules, fans, and
power supplies, gathered into enclosures.
One or more host servers attached to the storage array can access the data on
the storage array. You can also establish multiple physical paths between the
host(s) and the storage array so that loss of any single path (for example,
through failure of a host server port) does not result in loss of access to data
on the storage array.
The storage array is managed by MDSM running on a:
• Host server—On a host server system, MDSM and the storage array
communicate management requests and event information using
SAS connections.
• Management station—On a management station, MDSM communicates
with the storage array either through an Ethernet connection to the
storage array management port or through an Ethernet connection to a
host server. The Ethernet connection passes management information
between the management station and the storage array using SAS
connections.
Using MDSM, you can configure the physical disks in the storage array into
logical components called disk groups and then divide the disk groups into
virtual disks. Disk groups are created in the unconfigured capacity of a storage
array. Virtual disks are created in the free capacity of a disk group.
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Introduction 9
Unconfigured capacity comprises physical disks not already assigned to a disk
group. When a virtual disk is created using unconfigured capacity, a disk
group is automatically created. If the only virtual disk in a disk group is
deleted, the disk group is also deleted. Free capacity is space in a disk group
that is not assigned to any virtual disk.
Data is written to the physical disks in the storage array using RAID
technology. RAID levels define the way in which data is written to physical
disks. Different RAID levels offer different levels of accessibility, redundancy,
and capacity. You can set a specified RAID level for each disk group and
virtual disk on your storage array.
For more information about using RAID and managing data in your storage
solution, see the Owner’s Manual at dell.com/support/manuals.
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10 Introduction
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Hardware Installation 11
2
Hardware Installation
Before using this guide, ensure that you review the instructions in the:
• Getting Started Guide—The Getting Started Guide that shipped with the
storage array provides information to configure the initial setup of the system.
• Planning section of the Owner’s Manual—The planning section provides
information about important concepts you must know before setting up
your storage solution. See the Owner’s Manual at
dell.com/support/manuals.
Planning the Storage Configuration
Consider the following before installing your storage array:
• Evaluate data storage needs and administrative requirements.
• Calculate availability requirements.
• Decide the frequency and level of backups, such as weekly full backups
with daily partial backups.
• Consider storage array options, such as password protection and e-mail
alert notifications for error conditions.
• Design the configuration of virtual disks and disk groups according to a data
organization plan. For example, use one virtual disk for inventory, a second
for financial and tax information, and a third for customer information.
• Decide whether to allow space for hot spares, which automatically replace
failed physical disks.
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12 Hardware Installation
Connecting the Storage Array
The storage array is connected to a host using two hot-swappable RAID
controller modules. The RAID controller modules are identified as RAID
controller module 0 and RAID controller module 1.
For more information, see the Getting Started Guide.
Each RAID controller module has four SAS In port connectors that provide
SAS connections to the host or node. Each RAID controller module also
contains an Ethernet management port and a SAS Out port connector. The
Ethernet management port allows you to install a dedicated management
station (server or stand-alone system). The SAS Out port allows you to
connect the storage array to optional expansion enclosures for additional
storage capacity. For more information, see the Getting Started Guide.
Each Dell PowerVault MD3200 series storage array can be expanded to a
maximum of 120 (or 192, if enabled through the Premium Feature activation)
physical disks through a maximum of seven PowerVault MD1200 series
expansion enclosures.
NOTE: When you connect a host server to a storage array SAS In port connector,
any Out port connector of the server's host bus adapter (HBA) can be used.
Cabling the Storage Array
You can cable the storage array to host servers with:
• Single path data configuration—A single path configuration allows you to
connect a maximum of eight hosts. This is a non-redundant configuration.
• Dual path data configuration—A dual path configuration allows you to
connect a maximum of four hosts.
Choose the data configuration based on:
• Number of hosts required
• Level of data redundancy required
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Hardware Installation 13
Redundant and Non-Redundant Configurations
Non-redundant configurations are configurations that provide only a single
data path from a host to the storage array. This type of configuration is only
recommended for non-critical data storage. Path failure from a failed or
removed cable, a failed HBA, or a failed or removed RAID controller module
results in loss of host access to storage on the storage array.
Redundancy is established by installing separate data paths between the host
and the storage array, in which each path is set to one of the two RAID
controller modules installed in the storage array. Redundancy protects the
host from losing access to data in the event of path failure, because both
RAID controller modules can access all the disks in the storage array.
Single Controller Configurations
Figure 2-1 through Figure 2-3 show two and four hosts, each connected to
only one RAID controller module. The hosts can share storage space but
without redundant paths, if one path were to fail, the server on that path
would be disconnected from the storage array.
Figure 2-1. Two Hosts Connected to a Single Controller
Server 1 Server 2
Storage array
Corporate, public,
or private network
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14 Hardware Installation
Figure 2-2. Two Hosts Connected to a Single Controller
Server 1 Server 2
Storage array
Corporate, public,
or private network
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Hardware Installation 15
Figure 2-3. Four Hosts Connected to a Single Controller
Server 1 Server 2
Storage array
Corporate, public,
or private network
Server 3 Server 4
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16 Hardware Installation
Dual Controller Configurations
Figure 2-4 through Figure 2-6 show two and four hosts, each connected to two
RAID controller modules. Since each host has redundant paths, loss of a single
path would still allow access to the storage array through the alternate path.
Figure 2-4. Two Hosts Connected to Two Controllers
Server 1 Server 2
Storage array
Corporate, public,
or private network
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Hardware Installation 17
Figure 2-5. Four Hosts Connected to Two Controllers
Server 1 Server 2
Storage array
Corporate, public,
or private network
Server 3 Server 4
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18 Hardware Installation
Figure 2-6. Four Hosts Connected to Two Controllers
Server 1 Server 2
Storage array
Corporate, public,
or private network
Server 3 Server 4
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Hardware Installation 19
Figure 2-7 shows eight hosts, each connected to only one RAID controller
module. This configuration allows the maximum number of hosts that may
be connected, but provides no redundancy.
Figure 2-7. Eight Hosts Connected to Two Controllers
Server 1 Server 2
Storage array
Corporate, public,
or private network
Server 3 Server 4 Server 8
Up to 8 hosts
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20 Hardware Installation
Figure 2-8 and Figure 2-9 show up to four cluster nodes connected to two
RAID controller modules. Since each cluster node has redundant paths, loss
of a single path would still allow access to the storage array through the
alternate path.
Figure 2-8. Four Cluster Nodes Connected to Two Controllers
Four cluster nodes
Storage array
Corporate, public,
or private network
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Hardware Installation 21
Figure 2-9. Four Cluster Nodes Connected to Two Controllers
Four cluster nodes
Storage array
Corporate, public,
or private network
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22 Hardware Installation
Cabling PowerVault MD1200 Series Expansion
Enclosures
You can expand the capacity of your PowerVault MD3200 series storage array
by adding PowerVault MD1200 series expansion enclosures. You can expand
the physical disk pool to a maximum of 120 (or 192, if enabled using the
Premium Feature activation) physical disks using a maximum of seven
expansion enclosures.
Expanding With Previously Configured PowerVault MD1200 Series
Expansion Enclosures
Use this procedure if your expansion enclosure is directly attached to and
configured on a Dell PowerEdge RAID Controller (PERC) H800 adapter.
Data from virtual disks created on a PERC H800 adapter cannot be directly
migrated to a PowerVault MD3200 series storage array or to a PowerVault
MD1200 series expansion enclosure connected to a PowerVault MD3200
series storage array.
CAUTION: If a PowerVault MD1200 series enclosure that was previously attached
to PERC H800 adapter is used as an expansion enclosure to a PowerVault MD3200
series storage array, the physical disks of the expansion enclosure are
reinitialized and data is lost. You must backup all data on the expansion enclosure
before attempting the expansion.
To attach previously configured PowerVault MD1200 series expansion
enclosures to the PowerVault MD3200 series storage array:
1 Back up all data on the expansion enclosure(s).
2 Upgrade the expansion enclosure firmware to the latest version available
at dell.com/support while the enclosure is still attached to the PERC
H800 controller.
Windows systems users can reference the DUP
.exe package and Linux
kernel users can reference the DUP.bin package.
3 Ensure that the storage array software is installed and up to date before
adding the expansion enclosure(s).
For more information, see the Support Matrix at
dell.com/support/manuals.
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Hardware Installation 23
a Install the software and driver package included on the PowerVault
MD series resource media.
For information about installing the software, see "Installing
PowerVault MD Storage Software" on page 27.
b Update the storage array RAID controller module firmware and
NVSRAM to the latest versions available at dell.com/support, using
PowerVault MDSM.
c Click Tools Upgrade RAID Controller Module Firmware in the
Enterprise Management Window (EMW).
4 Stop all I/O and turn off the system and attached units.
a Stop all I/O to the array and turn off the host systems attached to the
storage array.
b Turn off the storage array.
c Turn off the expansion enclosure(s) in the affected system.
5 Cable the expansion enclosure(s) to the storage array.
6 Turn on attached units:
a Turn on the expansion enclosure(s). Wait for the enclosure status
LED to light blue.
b Turn on the storage array and wait for the status LED to indicate that
the unit is ready:
• If the status LEDs are solid amber, the storage array is still coming
online.
• If the status LEDs are blinking amber, there is an error that can be
viewed using the PowerVault MDSM.
• If the status LEDs are solid blue, the storage array is ready.
c When the storage array is online and ready, turn on any attached host
systems.
7 After the PowerVault MD1200 series expansion enclosure is configured as
an expansion enclosure of the storage array, restore the data that was
backed up in step 1.
After the PowerVault MD1200 series expansion enclosures are online, they
can be accessed as a part of the storage array.
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24 Hardware Installation
Expanding With New PowerVault MD1200 Series Expansion Enclosures
Perform the following steps to attach new PowerVault MD1200 series
expansion enclosures to a PowerVault MD3200 series storage array:
1 Before adding the expansion enclosure(s), ensure that the storage array
software is installed and is up to date. For more information, see the
Support Matrix at dell.com/support/manuals.
a Install the software and driver package included on the PowerVault
MD series resource media.
For information about installing the software, see "Installing
PowerVault MD Storage Software" on page 27.
b Set up the PowerVault MD1200 series expansion enclosure(s).
For information about setting up the PowerVault MD1200 series
expansion enclosure(s), see the Owner’s Manual at
dell.com/support/manuals.
c Using PowerVault MDSM, update the RAID controller module
firmware and NVSRAM to the latest versions available on
dell.com/support.
d Click Tools Upgrade RAID Controller Module Firmware from the
Enterprise Management Window (EMW).
2 Stop I/O and turn off the system and attached units:
a Stop all I/O to the storage array and turn off affected host systems
attached to the storage array.
b Turn off the storage array.
c Turn off any expansion enclosure(s) in the affected system.
3 Cable the expansion enclosure(s) to the storage array.
4 Turn on attached units:
a Turn on the expansion enclosure(s). Wait for the enclosure status
LED to light blue.
b Turn on the storage array and wait for the status LED to indicate that
the unit is ready:
• If the status LEDs are solid amber, the storage array is still coming
online.
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Hardware Installation 25
• If the status LEDs are blinking amber, there is an error that can be
viewed using PowerVault MDSM.
• If the status LEDs are solid blue, the storage array is ready.
c After the storage array is online and ready, turn on any attached host
systems.
5 Using MDSM, update all attached expansion enclosure firmware if it is out
of date:
a From the EMW, select the enclosure that you want to update and
enter the Array Management Window (AMW).
b Click AdvancedMaintanence DownloadEMM Firmware.
c Select Select All to update all the attached expansion enclosures
simultaneously.
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26 Hardware Installation
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Installing PowerVault MD Storage Software 27
3
Installing PowerVault MD Storage
Software
The Dell PowerVault MD series resource media contains software and drivers
for both Linux and Microsoft Windows operating systems.
The root of the media contains a readme.txt file covering changes to the
software, updates, fixes, patches, and other important data applicable to both
the Linux and Windows operating systems. The readme.txt file also specifies
requirements for accessing documentation, information regarding versions of
the software on the media, and system requirements for running the software.
For more information on supported hardware and software for PowerVault
systems, see the Support Matrix located at dell.com/support/manuals.
NOTE: It is recommended that you install all the latest updates available at
dell.com/support.
The PowerVault MD series resource media storage software installer provides
features that include the core software and providers. The core software feature
includes the host-based storage agent, multipath driver, and PowerVault MD
Storage Manager application used to configure, manage, and monitor the
storage array solution. The providers feature include providers for the Microsoft
Virtual Disk Service (VDS) and Microsoft Volume Shadow-Copy Service (VSS)
framework.
NOTE: For more information about the Microsoft VDS and Microsoft VSS providers,
see the Owner's Manual at dell.com/support/manuals.
NOTE: To install the software on a Windows or Linux system, you must have
administrative or root privileges.
The PowerVault MD series resource media offers the following three
installation methods:
• Graphical Installation (Recommended)—This is the recommended
installation procedure for most users. The installer presents a graphical
wizard-driven interface that allows customization of components to be
installed.
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28 Installing PowerVault MD Storage Software
• Console Installation—This installation procedure is useful for Linux users
who do not want to install an X-Window environment on their supported
Linux platform.
• Silent Installation—This installation procedure is useful for users who
want to create scripted installations.
Graphical Installation (Recommended)
The PowerVault MD Storage Manager application configures, manages, and
monitors the storage array. To install the PowerVault storage software:
1 Insert the PowerVault MD series resource media.
Depending on your operating system, the installer may launch
automatically. If the installer does not launch automatically, navigate to
the root directory of the installation media (or downloaded installer
image) and run the md_launcher.exe file. For Linux-based systems,
navigate to the root of the resource media and run the autorun file.
NOTE: By default, Red Hat Enterprise Linux mounts the resource media with the
–noexec mount option, which does not allow you to run executable files. To change
this setting, see the Readme file in the root directory of the installation media.
2 Select Install MD Storage Software.
3 Read and accept the license agreement.
4 Select one of the following installation options from the Install Set
dropdown menu:
• Full (recommended)—Installs the PowerVault MD Storage Manager
(client) software, host-based storage agent, multipath driver, and
hardware providers.
• Host Only—Installs the host-based storage agent and multipath
drivers.
• Management—Installs the management software and hardware
providers.
• Custom—Allows you to select specific components.
5 Select the PowerVault MD storage array model(s) you are setting up to
serve as data storage for this host server.
6 Choose whether to start the event monitor service automatically when the
host server reboots or manually.
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Installing PowerVault MD Storage Software 29
NOTE: This option is applicable only to Windows client software installation.
7 Confirm the installation location and choose Install.
8 If prompted, reboot the host server once the installation completes.
9 Start MD Storage Manager and discover the array(s).
10 If applicable, activate any premium features purchased with your storage
array.
If you purchased premium features, see the printed activation card
shipped with your storage array.
NOTE: The MD Storage Manager installer automatically installs the required
drivers, firmware, and operating system patches/hotfixes to operate your storage
array. These drivers and firmware are also available at dell.com/support. See the
Support Matrix at dell.com/support/manuals for any additional settings and/or
software required for your specific storage array.
Console Installation
NOTE: Console installation only applies to Linux systems that are not running a
graphical environment.
The autorun script in the root of the resource media detects when there is no
graphical environment running and automatically starts the installer in a
text-based mode. This mode provides the same options as graphical installation.
Silent Installation
To run silent installation on a Windows system:
1 Copy the custom_silent.properties file in the /windows folder of the
installation media or image to a writable location on the host server.
2 Modify the custom_silent.properties file to reflect the features, models
and installation options to be used. Then, save the file.
3 Once the custom_silent.properties file is revised to reflect your specific
installation, run the following command to begin the silent installation:
mdss_install.exe –f <host_server_path>\
custom_silent.properties
To run silent installation on a Linux system:
NOTE: On Red Hat Enterprise Linux 6 operating systems, run the following
script from the root directory to install prerequisite packages.
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30 Installing PowerVault MD Storage Software
# md_prereq_install.sh
1 Copy the custom_silent.properties file in the /windows folder of the
installation media or image to a writable location on the host server.
2 Modify the custom_silent.properties file to reflect the features, models
and installation options to be used.
3 Save the file.
4 Once the custom_silent.properties file is revised, run the following
command to begin the installation:
./mdss_install.bin –f
<host_server_path>/custom_silent.properties
Upgrading PowerVault MD Storage Software
To upgrade from a previous version of the PowerVault MD Storage Manager
application, uninstall the previous version (see "Uninstalling MD Storage
Software From Windows" on page 45), and then follow the instructions in
"Installing PowerVault MD Storage Software" on page 27 to install the new
version.
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Post Installation Tasks 31
4
Post Installation Tasks
Before using the storage array for the first time, complete the initial
configuration tasks in the order shown. These tasks are performed using the
MD Storage Manager.
NOTE: If Dynamic Host Configuration Protocol (DHCP) is not used, initial configuration
using the management station must be performed on the same physical subnet as the
storage array. Additionally, during initial configuration, at least one network adapter
must be configured on the same IP subnet as the storage array’s default management
port (192.168.128.101 or 192.168.128.102). After initial configuration, the management
ports are configured using MD Storage Manager and the management station’s IP
address can be changed back to the previous settings.
Before You Begin
NOTE: Before you begin configuring iSCSI, it is recommended that you fill out the
IPv4 or IPv6 iSCSI configuration worksheet available in this document, see "IPv4
Settings—Worksheet" on page 33 and "IPv6 Settings—Worksheet" on page 34.
Gathering this type of information about your network before starting the
configuration steps helps you to complete the process more efficiently.
iSCSI Configuration Terminology
Table 4-1. Standard Terminology Used in iSCSI Configuration
Term Definition
CHAP (Challenge Handshake
Authentication Protocol)
An optional security protocol used to control
access to an iSCSI storage system by restricting
use of the iSCSI data ports on both the host
server and storage array. For more information
on the types of CHAP authentication
supported, see "Understanding CHAP
Authentication" on page 62.
Host or host server A server connected to the storage array using
iSCSI ports.
Host server port SCSI port on the host server used to connect
it to the storage array.
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32 Post Installation Tasks
iSCSI Configuration Worksheet
The "IPv4 Settings—Worksheet" on page 33 and "IPv6 Settings—Worksheet"
on page 34 helps you plan your configuration. Recording host server and
storage array IP addresses at a single location enables you to configure your
setup faster and more efficiently.
"Guidelines For Configuring Your Network For iSCSI" on page 40 provides
general network setup guidelines for both Microsoft Windows and Linux
environments. It is recommended that you review these guidelines before
completing the worksheet.
iSCSI initiator The iSCSI-specific software installed on the
host server that controls communications
between the host server and the storage array.
iSCSI host port The iSCSI port (two per controller) on the
storage array.
iSNS (Microsoft Internet Storage
Naming Service)
An automated discovery, management and
configuration Storage Naming Service) tool
used by some iSCSI devices.
Management station The system from which you manage your
host server/storage array configuration.
Storage array The enclosure containing the storage data
accessed by the host server.
Target An iSCSI port on the storage array that
accepts and responds to requests from the
iSCSI initiator installed on the host server.
Table 4-1. Standard Terminology Used in iSCSI Configuration
Term Definition
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Post Installation Tasks 33
IPv4 Settings—Worksheet
Mutual CHAP
Secret
Target CHAP
Secret
A
B
host server
PowerVault
MD36x0i
192.168.131.101 (In 1 default) 192.168.128.101 (management network port)
192.168.130.102 (In 0 default)
192.168.131.102 (In 1 default)
192.168.128.102 (management network port)
If you need additional space for more than one host server, use an additional sheet.
iSCSI port 1
iSCSI port 2
Management port
Management port
Static IP address (host server)
Subnet
Default gateway
(should be different for each NIC)
A
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
Static IP address (host server) Subnet Default gateway
B
iSCSI controller 0, In 0
iSCSI controller 0, In 1
Management port cntrl 0
iSCSI controller 1, In 0
iSCSI controller 1, In 1
Management port cntrl 1
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
192.168.130.101 (In 0 default)
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34 Post Installation Tasks
IPv6 Settings—Worksheet
Mutual CHAP
Target CHAP
A
B
If you need additional space for more than one host server, use an additional sheet.
Link local IP address
Routable IP address
Subnet prefix
Gateway
A
Host server
Host iSCSI port 1
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
Link local IP address
Routable IP address
Subnet prefix
Gateway
Host iSCSI port 2
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
___ . ___ . ___ . ___
iSCSI controller 0, In 0
IP address
Routable IP address 1
Routable IP address 2
Router IP address
B
iSCSI controller 0, In 1
IP address
Routable IP address 1
Routable IP address 2
Router IP address
FE80 : 0000 : 0000 : 0000 : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
FE80 : 0000 : 0000 : 0000 : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
PowerVault MD36x0i
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Post Installation Tasks 35
Configuring iSCSI on Your Storage Array
The following sections contain step-by-step instructions for configuring
iSCSI on your storage array. However, before you begin, it is important to
understand where each of these steps occur in relation to your host server or
storage array environment.
The following table shows each iSCSI configuration step and where it occurs.
iSCSI controller 1, In 0
IP address
Routable IP address 1
Routable IP address 2
Router IP address
FE80 : 0000 : 0000 : 0000 : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
iSCSI controller 1, In 1
IP address
Routable IP address 1
Routable IP address 2
Router IP address
FE80 : 0000 : 0000 : 0000 : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
____ : ____ : ____ : ____ : ____ : ____ : ____ : ____
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36 Post Installation Tasks
Table 4-2. Host Server Vs. Storage Array
NOTE: It is recommended that you use the PowerVault Modular Disk Configuration
Utility (MDCU) for iSCSI configuration. The PowerVault MDCU wizards guides you
through the configuration steps described above. If you want to perform a manual
configuration, see "Appendix—Manual Configuration of iSCSI" on page 53.
Automatic Configuration Using the Modular Disk Configuration Utility
NOTE: If MDCU is not installed, it can be installed from the MD series resource
media.
The MDCU provides a consolidated approach for configuring the iSCSI network
of host servers and iSCSI-based storage arrays using a wizard-driven interface.
This utility also enables the user to configure the iSCSI sessions of the host server
according to the best practices and to achieve load-balanced paths with the
storage array iSCSI host ports. If you select Launch the MDCU after reboot
during the installation of the host software, the utility automatically launches
after the next host server reboot. This utility can also be launched manually.
The utility has a context sensitive online help to guide you through each step
of the wizard.
This Step is Performed on the Host Server
Using the Microsoft or Linux iSCSI Initiator
This Step is Performed on the Storage
Array Using PowerVault MD Storage
Manager
1 Discover the storage array
2 Configure the iSCSI ports on the
storage array
3 Perform target discovery from the iSCSI
initiator
4 Configure host access
5 (Optional) Configure CHAP
authentication on the storage array
6 (Optional) Configure CHAP
authentication on the host server
7 Connect to the storage array from the
host server
8 (Optional) Set up in-band management
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Post Installation Tasks 37
The MDCU performs:
• Storage array configuration
• Host configuration
Storage Array Configuration
Before a host iSCSI initiator and an iSCSI-based storage array can
communicate, they must be configured with information such as which IP
addresses and authentication method to use. Since iSCSI initiators establish
connections with an already configured storage array, the first task is to
configure your storage arrays to make them available for iSCSI initiators.
This utility requires network access to the management ports of the storage arrays
you wish to configure. You must have a properly functioning network
infrastructure before attempting to configure your storage arrays. If your storage
arrays are already configured, you can skip directly to the host configuration.
This configuration task generally involves the following steps:
1 Discover available storage array(s) for configuration.
2 Select a storage array to configure.
3 Set a storage array name and password.
4 Configure the IP protocols and addresses for the management ports.
5 Configure the IP protocols and addresses for the iSCSI ports.
6 Specify the CHAP authentication method.
7 Apply the settings after reviewing a summary.
8 Repeat the process starting from step 2 to configure additional arrays.
Host Configuration (Host Connectivity Configuration)
After you have completed configuring your iSCSI-based storage arrays, the
next task is to run this utility on all hosts that need to access the storage
arrays. Depending on your network configuration, your host may be the same
machine you use to manage your storage arrays, or it may be on a completely
separate network.
The option to configure a host is disabled if the machine on which the utility
is running does not have an iSCSI initiator or the required driver components
installed. When the option is disabled, the utility also displays an
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38 Post Installation Tasks
informational message. If you are running the utility on a host which is not
connected to the iSCSI–based storage array (or which you do not wish to
connect to the array), the informational message can be ignored.
The task generally involves the following steps:
1 Discover available storage array(s) for connection.
2 Select a storage array.
3 Specify the CHAP secret.
4 Select the iSCSI ports the host's initiator uses to log on.
5 Repeat the process starting from step 2 to connect to additional arrays.
6 Repeat these steps on each host that needs access to the storage array(s).
Before Starting the Configuration Process
Before you start configuring the storage array or host connectivity, it is
recommended that you fill out the iSCSI configuration worksheet to help you
plan your configuration. You may need to use several worksheets depending
on your configuration.
Keep the following guidelines in mind for the storage array and host
configuration:
• For optimal performance, ensure your network configuration.See the
storage array's Support Matrix at dell.com/support/manuals.
• If your host has multiple network interfaces, it is recommended that each
network interface uses a separate subnet.
• For redundancy in a dual controller (duplex) configuration, ensure each
host network interface is configured to connect to both storage array
controllers.
• For optimal load balancing, ensure each host network interface that is used
for iSCSI traffic is configured to connect to each storage array controller.
• It is recommended that each host network interface only establishes one
iSCSI session per storage array controller.
NOTE: The utility tries to follow the guidelines for the host connectivity whenever
possible based on the available host network interfaces and their connectivity with
the iSCSI host ports of the storage array.
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Post Installation Tasks 39
Configure the Storage Array Using MDCU
To configure the iSCSI-based storage array(s) using the MDCU:
1 Launch the utility (if it is not launched automatically) from the server
with access to the management ports of the storage array(s) to be
configured.
For Windows, click StartAll ProgramsDellMD Storage
SoftwareModular Disk Configuration Utility.
For Linux, click the MDCU icon on the desktop or navigate to the
/opt/dell/mdstoragesoftware/mdconfigurationutility directory in a
terminal window and run PowerVault MDCU.
The MDCU automatically discovers all the available storage arrays.
2 In the Discover MD Arrays window, select the iSCSI storage array you
want to configure.
3 In the Selected Array window, review current port and session information.
4 Click Config Wizard, to start the iSCSI configuration wizard.
5 Complete the steps in Config Wizard to configure your iSCSI storage
array.
6 In the Array Configuration Summary window, review and apply your
configuration settings.
7 Click Create iSCSI Sessions, to create host-to-storage array
communication.
Repeat for all host-to-array mappings you want to implement
8 Verify that communication is established between the storage array and
host server.
NOTE: For more information on MDCU, see the MDCU online help.
Post Connection Establishment Steps
After iSCSI connectivity is established between the host server(s) and the
storage array, you can create virtual disks on the storage array using MD
Storage Manager and these virtual disks can be utilized by the host server(s).
For more information about storage planning and using MD Storage
Manager, see the Administrator's Guide at dell.com/support/manuals.
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40 Post Installation Tasks
Guidelines For Configuring Your Network For
iSCSI
This section provides general guidelines for setting up your network
environment and IP addresses for use with the iSCSI ports on your host server
and storage array. In order for hosts to communicate with management and/or
iSCSI ports of storage arrays, local NICs must be configured with IP addresses
capable of communication with the addresses listed in the IPv4/IPv6
worksheet. Your specific network environment may require different or
additional steps than shown here, so make sure you consult with your system
administrator before performing this setup.
Microsoft Windows Host Setup
To set up a Windows host network, you must configure the IP address and
netmask of each iSCSI port connected to the storage array. The specific steps
depend on whether you are using a Dynamic Host Configuration Protocol
(DHCP) server, static IP addressing, Domain Name System (DNS) server, or
Windows Internet Name Service (WINS) server.
NOTE: The server IP addresses must be configured for network communication to
the same IP subnet as the storage array management and iSCSI ports.
Using A DHCP server
1 In the Control Panel, select Network connections or Network and
Sharing Center and then click Manage network connections.
2 Right-click the network connection you want to configure and
select Properties.
3 On the General tab (for a local area connection) or the Networking tab
(for all other connections), select Internet Protocol (TCP/IP), and then
click Properties.
4 Select Obtain an IP address automatically, then click OK.
Using static IP addressing
1 In the Control Panel, select Network connections or Network and Sharing
Center and then click Manage network connections.
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Post Installation Tasks 41
2 Right-click the network connection you want to configure and select
Properties.
3 On the General tab (for a local area connection) or the Networking tab
(for all other connections), select Internet Protocol (TCP/IP), and then
click Properties.
4 Select Use the following IP address and enter the IP address, subnet mask,
and default gateway addresses.
Using A DNS server
1 In the Control Panel, select Network connections or Network and Sharing
Center and then click Manage network connections.
2 Right-click the network connection you want to configure and select
Properties.
3 On the General tab (for a local area connection) or the Networking tab
(for all other connections), select Internet Protocol (TCP/IP), and then
click Properties.
4 Select Obtain DNS server address automatically or enter the preferred
and alternate DNS server IP addresses and click OK.
Using A WINS Server
NOTE: If you are using a DHCP server to allocate WINS server IP addresses, you
do not need to add WINS server addresses.
1 In the Control Panel, select Network connections.
2 Right-click the network connection you want to configure and select
Properties.
3 On the General tab (for a local area connection) or the Networking tab
(for all other connections), select Internet Protocol (TCP/IP), and then
click Properties.
4 Select Advanced WINS tab and click Add.
5 In the TCP/IP WINS server window, type the IP address of the WINS
server and click Add.
6 To enable use of the Lmhosts file to resolve remote NetBIOS names, select
Enable LMHOSTS lookup.
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42 Post Installation Tasks
7 To specify the location of the file that you want to import into the
Lmhosts file, select Import LMHOSTS and then select the file in the
Open dialog box.
8 Enable or disable NetBIOS over TCP/IP.
If using Microsoft Windows Server 2008 Core Version, use the netsh
interface command to configure the iSCSI ports on the host server.
Linux Host Setup
To set up a Linux host network, you must configure the IP address and
netmask of each iSCSI port connected to the storage array. The specific steps
depend on whether you are configuring TCP/IP using DHCP or configuring
TCP/IP using a static IP address.
NOTE: The server IP addresses must be configured for network communication to
the same IP subnet as the storage array management and iSCSI ports.
Using DHCP
If you are using DHCP (root users only):
1 Edit the /etc/sysconfig/network file:
NETWORKING=yes HOSTNAME=mymachine.mycompany.com
2 Edit the configuration file for the connection you want to configure, either
/etc/sysconfig/network-scripts/ifcfg-ethX (for Red Hat Enterprise Linux)
or /etc/sysconfig/network/ifcfg-eth-id-XX:XX:XX:XX:XX (for SUSE
Enterprise Linux).
BOOTPROTO=dhcp
Also, verify that an IP address and netmask are not defined.
3 Restart network services using the following command:
/etc/init.d/network restart
Using A Static IP Address
If you are using a static IP address (root users only)
1 Edit the /etc/sysconfig/network file as follows:
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Post Installation Tasks 43
NETWORKING=yes HOSTNAME=mymachine.mycompany.com
GATEWAY=255.255.255.0
2 Edit the configuration file for the connection you want to configure, either
/etc/sysconfig/network-scripts/ifcfg-ethX (for Red Hat Enterprise Linux)
or /etc/sysconfig/network/ifcfg-eth-id-XX:XX:XX:XX:XX (for SUSE
Enterprise Linux).
BOOTPROTO=static BROADCAST=192.168.1.255 IPADDR=
192.168.1.100 NETMASK=255.255.255.0 NETWORK=
192.168.1.0 ONBOOT=yes TYPE=Ethernet
HWADDR=XX:XX:XX:XX:XX:XX GATEWAY=192.168.1.1
3 Restart network services using the following command:
/etc/init.d/network restart
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44 Post Installation Tasks
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Uninstalling PowerVault MD Storage Software 45
5
Uninstalling PowerVault MD
Storage Software
Uninstalling MD Storage Software From
Windows
Use the Change/Remove Program feature to uninstall the Modular Disk
Storage Software (MDSM) from Microsoft Windows operating systems other
than Microsoft Windows Server 2008:
1 Double-click Add or Remove Programs from the Control Panel.
2 Select Dell MD32xxi storage software from the list of programs.
3 Click Change/Remove.
The Uninstall Complete window is displayed.
4 Follow the instructions on screen.
5 Select Yes to restart the system, and then click Done.
Use the following procedure to uninstall Modular Disk Storage software from
Windows Server 2008 GUI versions:
1 Double-click Programs and Features from the Control Panel.
2 Select MD Storage Software from the list of programs.
3 Click Uninstall/Change.
The Uninstall Complete window is displayed.
4 Follow the instructions on screen.
5 Select Yes to restart the system, then click Done.
Use the following procedure to uninstall PowerVault Modular Disk Storage
Software on Windows Server 2008 Core versions:
1 Navigate to the Dell\MD Storage Software\Uninstall Dell Modular Disk
32xxi Storage Software directory.
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46 Uninstalling PowerVault MD Storage Software
NOTE: By default, MD Storage Manager is installed in the \Program
Files\Dell\MD Storage Software directory. If another directory was used
during installation, navigate to that directory before beginning the
uninstallation procedure.
2 From the installation directory, type the following command and press
<Enter>:
Uninstall Modular Disk Storage
3 From the Uninstall window, click Next and follow the instructions on the
screen.
4 Select Yes to restart the system, then click Done.
Uninstalling MD Storage Software From Linux
1 By default, PowerVault MD Storage Manager is installed in the
/opt/dell/mdstoragemanager directory. If another directory was used
during installation, navigate to that directory before beginning the
uninstallation procedure.
2 From the installation directory, open the Uninstall Dell MD Storage
Software directory.
3 Run the file Uninstall Dell MD Storage Software.exe.
4 From the Uninstall window, click Next, and follow the instructions on the
screen.
While the software is uninstalling, the Uninstall window is displayed.
When the uninstall procedure is complete, the Uninstall Complete
window is displayed.
5 Click Done.
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Getting Help 47
6
Getting Help
Locating Your System Service Tag
Your system is identified by a unique Express Service Code and Service Tag
number. The Express Service Code and Service Tag are found on the front of
the system by pulling out the information tag. This information is used by
Dell to route support calls to the appropriate personnel.
Contacting Dell
NOTE: Dell provides several online and telephone-based support and service
options. If you do not have an active Internet connection, you can find contact
information on your purchase invoice, packing slip, bill, or Dell product catalog.
Availability varies by country and product, and some services may not be available
in your area.
To contact Dell for sales, technical support, or customer-service issues:
1 Go to dell.com/contactdell.
2 Select your country or region from the interactive world map.
When you select a region, the countries for the selected regions are
displayed.
3 Select the appropriate language under the country of your choice.
4 Select your business segment.
The main support page for the selected business segment is displayed.
5 Select the appropriate option depending on your requirement.
NOTE: If you have purchased a Dell system, you may be asked for the Service Tag.
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48 Getting Help
Documentation Feedback
If you have feedback for this document, write to
documentation_feedback@dell.com. Alternatively, you can click on the
Feedback link in any of the Dell documentation pages, fill up the form, and
click Submit to send your feedback.
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Appendix—Load Balancing 49
A
Appendix—Load Balancing
Windows Load Balance Policy
Multi-path drivers select the I/O path to a virtual disk through a specific
RAID controller module. When the multi-path driver receives a new I/O, the
driver tries to find a path to the current RAID controller module that owns
the virtual disk. If that path cannot be found, the multi-path driver migrates
the virtual disk ownership to the secondary RAID controller module. When
multiple paths to the RAID controller module that owns the virtual disk exist,
you can choose a load balance policy to determine which path is used to
process I/O. Multiple options for setting the load balance policies let you
optimize I/O performance when mixed host interfaces are configured.
You can choose one of the following load balance policies to optimize
I/O performance:
• Round robin with subset
• Least queue depth with subset
Round Robin With Subset
The round-robin with subset I/O load balance policy routes I/O requests, in
rotation, to each available data path to the RAID controller module that
owns the virtual disks. This policy treats all paths to the RAID controller
module that owns the virtual disk equally for I/O activity. Paths to the
secondary RAID controller module are ignored until ownership changes.
The basic assumption for the round-robin policy is that the data paths are
equal. With mixed host support, the data paths might have different
bandwidths or different data transfer speeds.
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50 Appendix—Load Balancing
Least Queue Depth With Subset
The least queue depth with subset policy is also known as the least I/Os, or
least requests, policy. This policy routes the next I/O request to a data path
that has the least outstanding I/O requests queued. For this policy, an I/O
request is simply a command in the queue. The type of command or the
number of blocks that are associated with the command are not considered.
The least queue depth with subset policy treats large block requests and small
block requests equally. The data path selected is in the path group of the
RAID controller module that owns the virtual disk.
Changing Load Balance Policies in Windows Sever 2008
Load balancing with the PowerVault MD3200 series is only available for
Windows Server 2008 and later versions of the operating system. You can
change the load balance policies from the default round robin with subset by
using one of the following:
• Device Manager options
• Disk Management options
Changing the Load Balance Policy Using Windows Server 2008 Device
Manager Options
1 Right-click My Computer and select Manage to open the Computer
Management window from the host desktop.
2 Click Device Manager to show the list of devices attached to the host.
3 Right-click the multi-path disk device for which you want to set load
balance policies, then select Properties.
4 Select the load balance policy you want to set for this disk device from the
MPIO tab.
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