Dell PowerVault NX1950 Guide

www.dell.com | support.dell.com
Dell™ PowerVault™ NX1950
Cluster Systems With
Dell|EqualLogic PS Series Storage Array
Installation and Troubleshooting Guide
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Notes, Notices, and Cautions
NOTE: A NOTE indicates important information that helps you make better use of
your computer.
NOTICE: A NOTICE indicates either potential damage to hardware or loss of data
and tells you how to avoid the problem.
CAUTION: A CAUTION indicates a potential for property damage, personal injury,
or death.
____________________
Information in this document is subject to change without notice.
© 2008 Dell Inc. All rights reserved.
Reproduction in any manner whatsoever without the written permission of Dell Inc. is strictly forbidden.
Trademarks used in this text: CommVault and CommVault Galaxy are registered trademarks of
CommVault Systems Inc.; Dell, the DELL logo, PowerVault, are trademarks of Dell Inc.; Microsoft,
SQL Server, Windows,Windows Server,MS-DOS are either trademarks or registered trademarks of
Microsoft Corporation in the United States and/or other countries.
Other trademarks and trade names may be used in this document to refer to either the entities claiming
the marks and names or their products. Dell Inc. disclaims any proprietary interest in trademarks and
trade names other than its own.
January 2008 Rev. A00
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Contents 3
Contents
1Overview. . . . . . . . . . . . . . . . . . . . . . . . . . 7
Using a PS Series SAN as Shared Storage . . . . . . . . 9
2 Planning the Network Configuration. . . . 13
Considering the Network Design Structure. . . . . . . 13
Planning Network Redundancy . . . . . . . . . . . . . 15
3 Setting Up the Cluster . . . . . . . . . . . . . . . 17
Pre-Installation Requirements . . . . . . . . . . . . . 17
Installing the Cluster. . . . . . . . . . . . . . . . . . . 17
4 Setting Up the
Dell|EqualLogic PS Series SAN . . . . . . . 21
Creating the Group. . . . . . . . . . . . . . . . . . . . 21
Configuring Volumes in a PS Series Storage Array. . . 22
Restricting Access to Volumes . . . . . . . . . . . . . 25
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4Contents
5 Configuring Shared Storage on Your
Dell|EqualLogic PS Series
Storage Array . . . . . . . . . . . . . . . . . . . . . 29
Connecting Nodes to Volumes. . . . . . . . . . . . . . 29
Aligning the Disk Sectors . . . . . . . . . . . . . . . . 32
Configuring a Basic Disk . . . . . . . . . . . . . . . . 32
Assigning a Drive Letter and
Formatting a Partition . . . . . . . . . . . . . . . . . . 32
6 Setting Up MSCS . . . . . . . . . . . . . . . . . . 33
Creating the Cluster . . . . . . . . . . . . . . . . . . . 33
Modifying the Cluster Network Configuration . . . . . 34
Adding a Node to the Cluster . . . . . . . . . . . . . . 37
Modifying Cluster Configuration Options . . . . . . . . 39
Testing Cluster Failover . . . . . . . . . . . . . . . . . 39
7 Expanding Your SAN Storage . . . . . . . . 41
Increasing the Size of a PS Series Volume . . . . . . . 41
Increasing PS Series Group Capacity . . . . . . . . . . 43
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Contents 5
8 Strategies for Backup and Recovery . . . 45
Protecting Cluster Data . . . . . . . . . . . . . . . . . 45
Choosing a Backup Method . . . . . . . . . . . . . . . 46
Restoring Data . . . . . . . . . . . . . . . . . . . . . . 47
9 Upgrading your SAN and Network . . . . . 49
Upgrading Components in Your Cluster . . . . . . . . . 49
10 Maintaining Your Cluster. . . . . . . . . . . . . 51
Replacing the Quorum Resource . . . . . . . . . . . . 51
Removing a Node from a Cluster . . . . . . . . . . . . 52
A Using WSRM and Scripts to
Manage Clusters . . . . . . . . . . . . . . . . . . . 55
B Migrating an Existing Cluster to
Dell|Equallogic PS Series Storage . . . . . 57
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
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6Contents
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Overview 7
Overview
The Dell™ PowerVault™ NX1950 cluster solution with Dell|EqualLogic
storage array combines Microsoft®Windows®Unified Data Storage Server
2003 clustering with a highly available and scalable Dell|Equallogic PS Series
storage array. Server clusters based on Microsoft®Cluster Service (MSCS)
provide availability for applications through failover. The following list
summarizes server cluster features:
• Provides features that can be used for databases, e-mail services, line of
business (LOB) applications, and custom applications.
• Includes Windows Unified Data Storage Server 2003.
• Provides high availability and server consolidation.
• Requires the use of shared storage.
NOTE: Throughout this document, PowerVault NX1950 storage system refers to the
individual storage unit and PowerVault NX1950 cluster solution refers to the
configuration of the storage unit along with the storage arrays.
In a PowerVault NX1950 cluster solution configuration, if the hardware or
software fails and causes a service failure, the cluster automatically restarts
the failed service on a functional cluster node. This service failover capability
ensures that no data is lost, and there is little disruption to users. When the
issue is corrected, the cluster can re-balance the services across all functional
nodes. The following figure illustrates a service failover on a typical cluster
configuration in which all nodes are running different services.
Figure 1-1 shows that Node A fails over to Node B.
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8Overview
Figure 1-1. Node A Fails Over to Node B
NOTE: Although most clustered services run on only one node at a time, a cluster
can run many services simultaneously to optimize hardware utilization.
public network
SAN network
cluster heartbeat
PS Series array
shared storage
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Overview 9
Using a PS Series SAN as Shared Storage
The PS Series storage array overcomes the challenges of DAS and traditional
SANs by providing a familiar technology for connecting servers to storage –
Ethernet. An iSCSI (Internet SCSI) SAN provides an affordable and
easy-to-manage shared storage solution for your cluster nodes. The basis of
the SAN is a PS Series storage array, a no-single-point-of-failure storage device
that combines reliability and scalability with an easy-to-use management
interface for a single system view of the storage connected to an IP network.
By grouping together one or more PS Series storage arrays, cluster nodes can
be connected to a pool of shared storage that provides:
• High availability — PS Series storage array hardware delivers redundant,
hot-swappable components like disks, control modules, fans, and power
supplies for a no-single-point-of-failure configuration. Components fail
over automatically without user intervention or disrupting data availability.
•
Improved data protection — All data is protected with Redundant Arrays
of Independent Disks (RAID) and spare disks. Full component redundancy
and hot service capabilities to ensure online operation.
•
Scalability — With a PS Series storage array, you can easily increase the
array capacity by installing additional drives or adding network connections.
You can also expand overall PS Series group capacity to terabytes of storage
by adding arrays to the group. The new arrays are configured automatically,
and the storage pool is expanded. During this process, data remains available
with no impact on hosts and applications. You do not have to open the
storage array or reconfigure an operating system. The additional storage
space is immediately available for use by any application on any server
because, in a cluster, all the servers have access to all the shared storage.
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10 Overview
• Easy and inexpensive management — The PS Series storage array has
offers centralized storage which enables you to manage more storage
efficiently. You can use a simple setup utility to configure an array on the
network and create a PS Series group and a functioning iSCSI SAN. You
can easily manage automation of complex operations like RAID
configuration, disk sparing, data provisioning, and load balancing to ensure
effectively managing the SAN.
•
Advanced management features — The PS Series comes standard with a
comprehensive set of features including automatic load balancing, virtual
volume management, space-efficient snapshots for instant backup and
restore, volume cloning for rapid server provisioning, multipath I/O
support, cluster support, and Auto-Replication capabilities delivering a
comprehensive disaster recovery solution.
Each array (member) in a group contributes disk space to the pool, which can
store the cluster quorum resource in addition to the data used by the cluster
applications. As needed, you allocate portions of the pool to volumes, specifying a
size, access controls, and other attributes. The PowerVault NX1950 storage
system sees each volume as a single device and each volume is automatically
load-balanced across multiple disks and group members as required.
Figure 1-2 shows a cluster configuration with a PS Series group as the shared
storage.
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Overview 11
Figure 1-2. Cluster Configuration With a PS Series Group as Shared Storage
1 Service 1 6 Quorum Volume
2 Service 2 7 service1_data Volume
3 Service 3 8 service2_data Volume
4 Service 4 9 service3_data Volume
5 Service 5 10 Test Volume
public network
SAN network
PowerVault
NX1950 A
PowerVault
NX1950 B
PowerVault
NX1950 C
cluster heartbeat
1
2
3
5
4
PS Series Array Shared Storage
67
8910
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12 Overview
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Planning the Network Configuration 13
Planning the Network Configuration
The following sections provide different possible network configurations and
help you plan for the implementation of Dell™ PowerVault™ NX1950 cluster
solution with Dell|EqualLogic PS Series storage.
Considering the Network Design Structure
Implementing the correct networking infrastructure is essential to
trouble-free operation of your PowerVault NX1950 cluster solution. This
section provides guidelines for designing networks for use with a cluster.
Typically you have a minimum of three networks in use:
• One or more data networks for applications — These are referred to as
public networks. A data network can be made redundant using Network
Interface Card (NIC) teaming or by using multiple interfaces on separate
subnets.
•
Heartbeat network — This is referred to as a private network. NIC teaming
cannot be used on the heartbeat network.
•
Storage area network (SAN) — The SAN can be made redundant by use of
Microsoft’s multipath I/O (MPIO). Multipath I/O provides more
intelligent, SAN-integrated load balancing capabilities.
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14 Planning the Network Configuration
The following SAN network guidelines are recommended for optimal
performance and high availability:
• Use a switched, Gigabit Ethernet network .
Connect storage arrays and hosts to a switched network and ensure that all
network connections between hosts and arrays are Gigabit Ethernet.
An array can operate at 10 and 100 Mbits, but performance is significantly
degraded.
•
Utilize fast convergence/fast spanning tree.
The Spanning Tree Protocol (STP) has a measurable convergence time.
When a switch participating in spanning tree fails, the protocol needs to
recalculate which is going to be the
root switch. During this time, you can
experience a network service interruption on that segment while this
re-convergence happens. Rapid Spanning Tree Protocol (RSTP) allows a
switch port to bypass the Spanning Tree listening and learning states and
quickly enter the STP forwarding state. Utilizing Rapid Spanning Tree
Protocol (RSTP, 802.1w) can speed up the time it takes to recalculate
spanning tree, thus reducing network service interruption. To verify if your
switches are RSTP-capable and how to configure for RSTP, see your switch
documentation.
•
Use flow control.
Enable Flow Control on each switch port that handles iSCSI traffic.
Enable Flow Control on the NICs to obtain any performance benefit. PS
Series storage arrays support Flow Control.
•
Enable Jumbo Frames.
If supported by all the devices in the network path between hosts and
arrays, enable Jumbo Frames on each switch that handles iSCSI traffic.
This support is usually disabled by default. Also enable Jumbo Frames on
the NICs that are responsible for iSCSI traffic to obtain any performance
benefit and ensure consistent behavior.
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Planning the Network Configuration 15
• Configure multiple network interfaces on an array.
Connect the network interfaces to different switches.
• For a multi-subnet PS Series group, provide access to the subnet on which the
group IP address for all enabled network interfaces on the group members.
•
Use redundant paths between iSCSI initiators and storage arrays.
Multipath I/O ensures that no single point of failure exists between initiators
and arrays. This can be achieved by using Microsoft’s MPIO solution.
For additional details on these guidelines, see the EqualLogic Customer
Support website at www.equallogic.com. You must create an account to
access contents of the EqualLogic Customer Support website.
Planning Network Redundancy
You must make the network fault tolerant like you make your applications
fault tolerant by deploying clusters. You have to apply certain rules when
configuring redundancy for the different network segments of your cluster as
described in "Considering the Network Design Structure" on page 13. The
public network can be made redundant using NIC teaming or by configuring
multiple interfaces on separate subnets. The network that is enabled for
internal communication between cluster nodes, typically a private network,
must not be teamed. The SAN network should use multipath I/O for
redundancy.
When used with a PS Series group, full cluster redundancy at the network
level may require five network ports. You can accomplish network redundancy
in the PowerVault NX1950 cluster solution by using the following:
• Teaming or multiple interfaces on separate subnets. These are the only two
supported options for the public network. For more information on
network adapters and drivers required for teaming to a specific
environment, see your network adapter documentation.
• Two or more NICs for SAN traffic, utilizing multipath I/O. NIC teaming
for iSCSI is not supported.
• One NIC for the private internal cluster communications or heartbeat. As
a best practice, ensure that the network adapters used in all cluster nodes
are identical. Whether using the
PowerVault NX1950 storage system on-
board (built-in) network adapters or add-on PCI/X cards, they should be
the same make, model, and firmware version on each network.
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16 Planning the Network Configuration
The following table shows an example of planning IP addresses for a cluster.
Table 2-1. Cluster Name and IP Assignment
Interface IP Address Subnet Mask Gateway Note
Node A
SAN 192.168.0.11 255.255.255.0 Gateway
optional
Using MPIO
SAN 192.168.0.12 255.255.255.0 Gateway
optional
Using MPIO
Public 172.16.100.212 255.255.255.0 172.16.12.1 Teamed/virtual
values
Private 10.10.10.1 255.255.255.0 N/A Do not assign
gateway
Node B
SAN 192.168.0.13 255.255.255.0 Gateway
optional
Using MPIO
SAN 192.168.0.14 255.255.255.0 Gateway
optional
Using MPIO
Public 172.16.100.222 255.255.255.0 172.16.12.1 Teamed/virtual
values
Private 10.10.10.2 255.255.255.0 N/A Do not assign
gateway
Cluster
Short
Name
IP Address FQDN (DNS) Note
cluster0 172.16.100.10 cluster0.acme.com Cluster configuration
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Setting Up the Cluster 17
Setting Up the Cluster
This section outlines the basic steps required to configure a Dell|EqualLogic
PS Series SAN as the shared storage for a Microsoft®Windows®Unified
Data Storage Server 2003 cluster. The steps assume that you have already
completed the hardware installation and setup of your group as described in
the PS Series QuickStart.
Because you are using a shared storage device, when you turn on the system
and start up the operating system, it is vitally important that only one node
has access to a shared volume at one time. Otherwise the shared volumes can
become corrupted. After the cluster service is running properly on one node,
you can add and configure the other nodes.
Pre-Installation Requirements
Ensure that all nodes are installed with the following:
1
Microsoft Windows Unified Data Storage Server 2003 Enterprise Service
Pack 2 or later
2 Microsoft iSCSI Software Initiator
3 Required number of NICs
NOTE: You require multiple NICs for the cluster configuration. For more
information, see the Installation Guide.
Installing the Cluster
1 Configure MPIO on each node using the Remote Setup Wizard.
Start → Equallogic → Remote Setup Wizard and select Configure MPIO
settings on this computer.
2 Add the Persistent Reservation Key MSiSCSI DSM to each node in the cluster:
a Select an 8-byte value that is unique to that cluster.
b Locate the following registry key at:
HKLM\System\CurrentControlSet\Services\MSiSCDSM\Persistent
Reservation.
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18 Setting Up the Cluster
c Add the following values: UsePersistentReservation
REG_DWORD
d Setting this value to 1 enables Persistent Reservation.
PersistentReservation KeyREG_BINARY <PR key> . This is an
8-byte binary value that is unique to the cluster. The same binary
value must be used on all nodes in the cluster.
3 Set the disk time out to 60 .
Set the value of
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\dis
k\TimeOutValue
to 60 seconds.
4 Set recovery of the iSCSI service:
a Select Start → Run and type Services.msc.
b Double click on the MS iSCSI initiator services.
c Select Recovery tab for directions to start recovery if the initiator
service fails.
d Select Restart the Service for all three scenarios.
e Set the Restart service after value to 0 .
5 From the first node, set up a PS Series group and create the volumes
required for the cluster environment.
Create the following volumes:
• Quorum resource volume. Microsoft requires that you configure the
quorum disk with a size of 512 MB.
• Volumes for service data, as needed.
Ensure that you have created one or more access control records for each
data volume to allow only the cluster nodes access to the volume. In
addition, reserve Snapshot space for each volume if you want to create
volume snapshots or use Auto-Snapshot Manager for VSS backups. For
more information, see "Setting Up the Dell|EqualLogic PS Series SAN" on
page 21.
6 Optimize the SAN network for performance.
For more information, see the EqualLogic Technical Report
Network
Connection and Performance Guidelines
.
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Setting Up the Cluster 19
7 On the first node, use the iSCSI initiator to connect to the shared volumes
and format the volumes.
a Start the iSCSI initiator and log in to the iSCSI targets associated
with the volumes you set up in step 1. Use the group IP address as the
target portal or discovery address.
b Ensure that you have established a persistent connection to the
volume and bound the volume so it is available when needed. After
establishing the connection, the volumes appear as disks in the
Disk
Management
utility.
c Align the disks sectors, configure each iSCSI disk as a basic disk, and
assign a drive letter. For more information, see "Configuring Shared
Storage on Your Dell|EqualLogic PS Series Storage Array" on page 29.
8 Allocate static IP addresses on your public network.
You require an IP address for the cluster. These are the
virtual IP addresses
that are utilized to access each cluster-configured resource.
9 Create a corresponding DNS name for each IP address you allocated in.
You must enter the name of the cluster application into your DNS system.
The DNS name is required to access the resources of the configured
cluster.
10 Create a unique Active Directory account for your cluster service to run
under.
For best practices, set up a new account for cluster service user. The
account must have local administrative rights and permissions on the
cluster nodes. Ensure that the password for the account does not expire.
(Follow your organization’s policies for password renewal.) It is strongly
recommended that you do not use the same account for the cluster service
and the applications in the cluster (for example, Microsoft SQL Server™).
If you do use the same account, you may not be able to later change the
cluster service password without disrupting your cluster applications.
11 Configure Microsoft Clustering Services on the first node.
For more information on configuring Microsoft Clustering Services, see
"Creating the Cluster" on page 33.
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20 Setting Up the Cluster
12 Modify the cluster network configuration.
For more information on modifying cluster network configuration, see
"Modifying the Cluster Network Configuration" on page 34.
13 On the second node, use the iSCSI initiator to connect to the shared PS
Series volumes.
Start the iSCSI initiator and log in to the iSCSI targets associated with the
volumes you set up in step 1. Use the group IP address as the target portal
or discovery address. Ensure that you have established a persistent
connection to the volume and have bound the volume so that it is
available when required. After the connection is established, the volumes
appear as disks in the
Disk Management utility.
NOTE: Do not align disk sectors or format the disk on the second node. It is
important to verify that the disks on the second node are labeled not initialized
(instead of online). This indicates that the SCSI reservation (to the first node) has
been honored by the storage sub-system. Therefore, one node will not be able to
corrupt data by writing to a disk that has been reserved by another node. See
"Connecting Nodes to Volumes" on page 29 for more information.
14 Add a second node to the cluster.
For more information on adding a second node, see "Adding a Node to the
Cluster" on page 37.
15 Consider modifying cluster configuration options.
For more information on modifying cluster configuration options, see
"Modifying Cluster Configuration Options" on page 39.
16 Test the cluster.
For more information on testing a cluster, see "Testing Cluster Failover" on
page 39.
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