Dell PowerVault MD3000 with Windows HA Clusters Quick Reference Guide

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Dell™ Failover Clusters With

Microsoft

and Windows Server 2008 R2

Software Installation and

Troubleshooting Guide

Windows Server® 2008

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October 2009 Rev A01

Contents

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . 7

Features of Failover Clusters Running Windows Server 2008

. . . . . . . . . . . . . . . . . . . 7

Supported Cluster Configurations

. . . . . . . . . . . . 10

Cluster Components and Requirements

Operating System

System Requirements

Cluster Nodes

Cluster Storage

Introduction

Dell™ Failover Cluster is a group of systems working together to run a common set of applications that presents a single logical system to client applications. The systems (or nodes) in the cluster are physically connected by either local area network (LAN) or wide area network (WAN) and are configured with the cluster software. If a system or the network connections in the cluster fail, the services on the active node failover to the passive node in the cluster.

NOTE: In this document, Microsoft® Windows Server® 2008 refers to either

Microsoft Windows Server 2008 or Microsoft Windows Server 2008 R2. For the list of Dell-validated operating systems for a Failover Cluster, see the Dell Cluster Configuration Support Matrices located on the Dell High Availability Clustering website at www.dell.com/ha.

Failover Clusters configured with Microsoft Windows Server 2008 operating systems provide high availability and scalability for mission-critical applications such as databases, messaging systems, file and print services, and virtualized workloads. If a node in a cluster becomes unavailable (as a result of failure or having been taken down for maintenance), another node in the cluster provides the same service. Users accessing the service continue their work and are unaware of any service disruption.

Windows Server 2008 includes functionality to simplify the cluster creation and administration. You can create an entire cluster in one seamless step through a wizard interface.

Features of Failover Clusters Running Windows Server 2008

The Failover Cluster running Windows Server 2008 implements up to 16 nodes in a cluster, depending on the storage array used, and provides the following features:

• A shared storage bus featuring Fibre Channel, Serial Attached SCSI (SAS), or Internet Small Computer System Interface (iSCSI) technology

• High availability of resources to network clients

Introduction 7

• Redundant paths to the shared storage

• Failure recovery for applications and services

• Flexible maintenance capabilities, allowing you to repair, maintain, or upgrade a node or storage system without taking the entire cluster offline

The services and capabilities that are included with Failover Clusters running Windows Server 2008 are:

• The Failover Cluster Management Interface — The Failover Cluster Management Interface is a task-oriented tool. To access the management interfaces,

Start→

•The Server 2008 include the built-in cluster

Microsoft Management Console 3.0

Programs→

Validate a Configuration

Administrative Tools

Wizard — The cluster tools in Windows

and

cluadmin.msc

Validate a Configuration

, go to

wizard to help detect the issue of a cluster failing due to configuration complexity. The

Validate a Configuration

wizard runs a set of tests on the systems in a

cluster, and performs the following functions:

– Checks the software inventory

– Tests the network and attached storage

– Validates system configuration

• New method to create clusters — You can install the Failover Clustering feature through the the

Server Manager

uninstall clustering using Windows Server 2008, you must use the

Initial Configurations Task

interface in

Administrative Tools

Server Manager

interface. For systems running

Add Feature

(ICT) interface or with

. You can also

Wizard to install the

Failover Clustering feature.

• Migrating legacy clusters — You can migrate your cluster that is running the Windows Server 2003 operating system to the Windows Server 2008 operating system. To access the migration functionality in Windows Server 2008, see the

Migrate Services and Applications

wizard, a report containing

wizard. After you run the

information about the migration tasks is created.

NOTE: You cannot configure nodes running the Windows Server 2003

operating system and nodes running the Windows Server 2008 operating system in the same cluster. In addition, Failover Cluster nodes must be joined to an Microsoft Active Directory Windows NT 4.0-based domain.

8 Introduction

based domain and not a

• Improvements in Scoping and Managing Shares — The process of creating a highly-available share with Failover Cluster running Windows Server 2008 is very simple when you use the also use the

Browse

button to quickly and reliably identify the folder you

Add a Shared Folder

wizard. You can

want to use for the highly-available share.

• Better Storage and Backup Support — The architecture of Failover Cluster running Windows Server 2008 has undergone storage related changes to improve stability and scalability.

• Enhanced Maintenance Mode — Use the

Maintenance

mode to perform maintenance and administrative tasks; like Volume Snapshots, ChkDsk, and so on; on the cluster disk resources. The

Maintenance

mode turns off cluster health monitoring on the cluster disk for a period of time so that it does not fail while maintenance is in-progress on the cluster disk.

• Superior Scalability — The Failover Cluster running Windows Server 2008 x64 can support 16 nodes. The Failover Cluster running Windows Server 2008 can also supports disks which use GUID Partition Table (GPT) disk partitioning system. GPT disks allow for 128 primary partitions as opposed to

in Master Boot Record (MBR) disks. Also, the partition size for GPT

disks can be more than 2 TB (the limit for an MBR disk).

• Quorum Model — The Windows Server 2008 Failover Clustering Quorum model is redesigned to eliminate the single point of failure which existed in previous versions. The four ways to establish a quorum are:

– No Majority - Disk Only (similar to Windows Server 2003 shared

disk quorum)

– Node Majority (similar to Windows Server 2003 Majority Node Set)

– Node and Disk Majority

– Node and File Share Majority

• Networking Capabilities — The Failover Cluster running Windows Server 2008 employs a new networking model which includes improved support for:

– Geographically distributed clusters

– Ability to have cluster nodes on different subnets

– DHCP server to assign IP addresses to cluster interfaces

– Improved cluster heartbeat mechanism and support for IPv6

Introduction 9

Supported Cluster Configurations

For the list of Dell-validated hardware, firmware, and software components for a Failover Cluster running Windows Server 2008, see the Dell Cluster Configuration Support Matrices located on the Dell High Availability Clustering website at www.dell.com/ha.

Cluster Components and Requirements

Your cluster requires the following components:

• Operating System

• Cluster nodes (servers)

• Cluster Storage

Operating System

Dell Failover Clusters supports Windows Server 2008 with x64 bit Enterprise Edition only. For a complete list of features, see the documentation for Windows Server 2008, x64 bit, Enterprise Edition.

NOTE: Running different operating systems in a cluster is supported only during

a rolling upgrade. You cannot upgrade your Failover Cluster running a different operating system to Windows Server 2008, Enterprise x64 Edition. Only a new cluster installation is permitted for Windows Server 2008, Enterprise x64 Edition.

System Requirements

The following sections list the requirements for cluster nodes and storage systems in a Failover Cluster running Windows Server 2008.

Cluster Nodes

Table 1-1 lists the hardware requirements for the cluster nodes.

Table 1-1. Cluster Node Requirements

Component Minimum Requirement

Cluster nodes At least two and up to 16 PowerEdge systems running the

Windows Server 2008 operating system.

RAM At least 512 MB of RAM installed on each cluster node.

10 Introduction

Table 1-1. Cluster Node Requirements (continued)

Component Minimum Requirement

NICs At least two NICs: one NIC for the public network and another

NIC for the private network.

NOTE: It is recommended that the NICs on each public network

are identical, and that the NICs on each private network are identical.

Internal disk controller

One controller connected to at least two internal hard drives for each node. Use any supported RAID controller or disk controller.

Two hard drives are required for mirroring (RAID 1) and at least three are required for disk striping with parity (RAID 5).

NOTE: It is strongly recommended that you use hardware-based

RAID or software-based disk-fault tolerance for the internal drives.

HBA ports

• For clusters with Fibre Channel storage, two Fibre Channel HBAs per node, unless the server employs an integrated or supported dual-port Fibre Channel HBA.

• For clusters with SAS storage, one or two SAS 5/E HBAs per node.

NOTE: Where possible, place the HBAs on separate PCI buses to

improve availability and performance. For information about supported systems and HBAs, see the Dell Cluster Configuration Support Matrices located on the Dell High Availability Clustering website at www.dell.com/ha.

iSCSI Initiator and NICs for iSCSI Access

For clusters with iSCSI storage, the iSCSI Software Initiator (including iSCSI port driver and Initiator Service) is installed with the operating system.

Two iSCSI NICs or Gigabit Ethernet NIC ports per node. NICs with a TCP/IP Off-load Engine (TOE) or iSCSI Off-load capability may also be used for iSCSI traffic.

NOTE: Where possible, place the NICs on separate PCI buses to

improve availability and performance. For information about supported systems and HBAs, see Dell Cluster Configuration Support Matrices on the Dell High Availability Clustering website at www.dell.com/ha.

Introduction 11

Cluster Storage

While configuring your Dell Failover Cluster with Windows Server 2008, attach all cluster nodes to a common shared storage. The type of storage array and topology in which the array is deployed can influence the design of your cluster. For example, a direct-attached SAS storage array may offer support for two cluster nodes whereas a SAN-attached Fibre Channel or iSCSI array has the ability to support sixteen cluster nodes.

A shared storage array enables data for clustered applications and services to be stored in a common location that is accessible by each cluster node. Although only one node can access or control a given disk volume at a point in time, the shared storage array enables other nodes to gain control of these volumes in the event that a node failure occurs. This also helps facilitate the ability of other cluster resources, which may depend upon the disk volume, to failover to the remaining nodes.

Additionally, it is recommended that you attach each node to the shared storage array using redundant paths. Providing multiple connections (or paths) between the node and the storage array reduces the number of single points of failure that could otherwise impact the availability of the clustered applications or services.

For details and recommendations related to deploying a Dell Failover Cluster solution with a storage array, see the "Cabling Your Cluster Hardware" section in the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

Preparing Your Systems for Clustering

WARNING: Only trained service technicians are authorized to remove and

access any of the components inside the system. See your safety information shipped with your system for complete information about safety precautions, working inside the system, and protecting against electrostatic discharge.

Cluster Configuration Overview

NOTE: For more information on step 1, step 2, and step 9, see the "Preparing Your

Systems for Clustering" section of the Dell Failover Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support site at support.dell.com/manuals. For more information on step 3 to step 7 and step 10 to step 14, see this chapter.

Ensure that your site can handle the cluster’s power requirements. For more information.

Contact your sales representative for information about your region's power requirements.

Install the systems, the shared storage array(s), and the interconnect switches (example: in an equipment rack), and ensure that all these components are powered on.

Deploy the operating system (including any relevant service pack and hotfixes), network adapter drivers, and storage adapter drivers (including MPIO drivers) on each of the systems that you want to configure as cluster nodes. Depending on the deployment method that is used, it may be necessary to provide a network connection to successfully complete this step.

NOTE: To help planning and deployment of your cluster, record the relevant

cluster configuration information in the "Cluster Data Form" and "Zoning Configuration Form" of Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

Preparing Your Systems for Clustering 15

Establish the physical network topology and the TCP/IP settings for network adapters on each cluster node to provide access to the cluster public and private networks.

Configure each cluster node as a member in the same Microsoft® Active Directory

Establish the physical storage topology and any required storage network

Domain.

settings to provide connectivity between the storage array and the systems that are configured as cluster nodes. For more information on configuring the storage system(s), see your storage system documentation.

Use storage array management tools to create at least one logical unit number (LUN). The LUN is used as a witness disk for Microsoft Windows

Server

2008 Failover Cluster. Ensure that this LUN is presented to the

systems that are configured as cluster nodes.

NOTE: For security reasons, it is recommended that you configure the LUN on

a single node, as mentioned in step 8 when you are setting up the cluster. Later you can configure the LUN as mentioned in step 9 so that other cluster nodes can access it.

Select one of the systems and form a new Failover Cluster by configuring the cluster name, cluster management IP, and quorum resource.

NOTE: For Failover Clusters configured with Windows Server 2008 operating

system, run the Cluster Validation Wizard to ensure that your system is ready to form the cluster.

Join the remaining node(s) to the Failover Cluster.

Configure roles for cluster networks. Take any network interfaces that are used for iSCSI storage (or for other purposes outside of the cluster) out of the control of the cluster.

Test the failover capabilities of your new cluster.

NOTE: For Failover Clusters configured with the Windows Server 2008

operating system, you can also use the Cluster Validation Wizard.

Configure highly-available applications and services on your Failover Cluster. Depending on your configuration, this may also require providing additional LUNs to the cluster or creating new cluster resource groups.

Test the failover capabilities of the new resources.

Configure client systems to access the highly-available applications and services that are hosted on your Failover Cluster.

16 Preparing Your Systems for Clustering

Installation Overview

This section provides installation overview procedures for configuring a cluster running the Windows Server

NOTE: The Storage management software may use different terms than those in

this guide to refer to similar entities. For example, the terms "LUN" and "Virtual Disk" are often used interchangeably to designate an individual RAID volume that is provided to the cluster nodes by the storage array.

Ensure that the cluster meets the requirements as described in "Cluster

2008 operating system.

Configuration Overview" on page 15.

Select a domain model that is appropriate for the corporate network and operating system.

See "Selecting a Domain Model" on page 19.

Reserve static IP addresses for the cluster resources and components, including:

• Public network

• Private network

• Cluster virtual servers

Use these IP addresses when you install the Windows

operating system

and Windows Server 2008 Failover Clustering (WSFC).

NOTE: WSFC supports configuring cluster IP address resources to obtain IP

address from a DHCP server in addition to through static entries. It is recommended that you use static IP addresses.

Configure the internal hard drives.

See "Configuring Internal Drives in the Cluster Nodes" on page 19.

Install and configure the Windows operating system.

The Windows operating system must be installed on all the cluster nodes. Each node must have a licensed copy of the Windows operating system, and a Certificate of Authenticity.

See "Installing and Configuring the Windows Operating System" on page 20.

Preparing Your Systems for Clustering 17

Install or update the storage connection drivers.

For more information on connecting your cluster nodes to a shared storage array, see "Preparing Your Systems for Clustering" in

the Dell Failover

Cluster Hardware Installation and Troubleshooting Guide that

corresponds to your storage array on the Dell Support website at support.dell.com/manuals.

For more information on the corresponding supported adapters and driver versions, see the Dell Cluster Configuration Support Matrices located on the Dell High Availability Clustering website at www.dell.com/ha.

Install and configure the storage management software.

See the documentation included with your storage system or available at the Dell Support website at

Configure the hard drives on the shared storage system(s).

support.dell.com/manuals

See "Configuring and Managing LUNs" in the Dell Failover Cluster Hardware Installation and Troubleshooting Guide storage array

Install and configure Failover Clustering feature.

on the Dell Support website at support.dell.com/manuals

corresponding to your

See "Configuring Your Failover Cluster" on page 29.

Verify cluster functionality. Ensure that:

• The cluster components are communicating properly.

• Cluster Service is started.

Verify cluster resource availability.

Use the Failover Cluster MMC to check the running state of each resource group.

The following subsections provide detailed information for the steps in the "Installation Overview" on page 17 that is specific to the Windows Server 2008 operating system.

18 Preparing Your Systems for Clustering

Selecting a Domain Model

On a cluster running the Microsoft Windows operating system, all nodes must belong to a common domain or directory model. The following configurations are supported:

• It is recommended that all nodes of High Availability applications are member systems in an Microsoft Active Directory

• All nodes are domain controllers in an Active Directory domain.

• At least one node is a domain controller in an Active Directory and the remaining nodes are member systems.

NOTE: If a node is configured as a domain controller, client system access to its

cluster resources can continue even if the node cannot contact other domain controllers. However, domain controller functions can cause additional overhead, such as log on, authentication, and replication traffic. If a node is not configured as a domain controller and the node cannot contact a domain controller, the node cannot authenticate client system requests.

domain.

Configuring Internal Drives in the Cluster Nodes

If your system uses a hardware-based RAID solution and you have added new internal hard drives to your system or you are setting up the RAID configuration for the first time, you must configure the RAID array using the RAID controller’s BIOS configuration utility before installing the operating system.

For the best balance of fault tolerance and performance, use RAID 1. See the RAID controller documentation for more information on RAID configurations.

NOTE: It is strongly recommended that you use hardware based RAID solution.

Alternately you can use the Microsoft Windows Disk Management tool to provide software-based redundancy.

Preparing Your Systems for Clustering 19

Installing and Configuring the Windows Operating System

CAUTION: Windows standby mode and hibernation mode are not supported in

cluster configurations. Do not enable either mode.

Ensure that the cluster configuration meets the requirements listed in "Cluster Configuration Overview" on page 15.

Cable the hardware.

NOTE: Do not connect the nodes to the shared storage systems at this time.

For more information on cabling your cluster hardware and the storage array that you are using, see "Cabling Your Cluster Hardware" in

Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

Install and configure the Windows Server 2008 operating system on each node.

Ensure that the latest supported version of network adapter drivers is installed on each cluster node.

Configure the public and private network adapter interconnects in each node, and place the interconnects on separate IP subnetworks using static IP addresses. See "Configuring Windows Networking" on page 21.

For information on required drivers, see

Support Matrices

www.dell.com/ha

located on the Dell High Availability website at

Dell Cluster Configuration

the Dell

Turn off all the cluster nodes and connect each cluster node to the shared storage.

For more information on cabling your cluster hardware and the storage array that you are using, see "Cabling Your Cluster Hardware"

Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

If required, configure the storage software.

Reboot node 1.

20 Preparing Your Systems for Clustering

in the Dell

From node 1, go to the disk signature, partition the disk, format the disk, and assign drive letters and volume labels to the hard drives in the storage system.

For more information, see "

Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

On node 1, verify disk accessibility and functionality on all shared disks. Verify disk access by performing the following steps on the second node:

Turn on the node.

Modify the drive letters to match the drive letters on node 1.

This procedure allows the Windows operating system to mount the volumes.

Close and reopen

Verify that the Windows operating system can access the file systems and the volume labels.

Install and configure the Failover Clustering feature from the

Manager

If required, install and setup the application programs.

Enter the cluster configuration information on the the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for your corresponding storage array

support.dell.com/manuals

Windows Disk Management

Preparing Your Systems for Clustering" in the

Disk Management

(optional).

on the Dell Support website at

application, write the

Server

Cluster Data Form

Configuring Windows Networking

You must configure the public and private networks in each node before you install Failover Clustering on the nodes. The following subsections introduce you to some principles and procedures necessary for the networking prerequisites.

Windows Server 2008 also introduces IPv6 support for clustering. You can have both node-to-node (private) as well as node-to-client (public) communication over IPv6. For more details on using IPv6, see "Configuring IPv6 addresses for Cluster Nodes" on page 24.

Preparing Your Systems for Clustering 21

Assigning Static IP Addresses to Cluster Resources and Components

NOTE: WSFC supports configuring cluster IP address resources to obtain

IP address from a DHCP server in addition to through static entries. It is recommended that you use static IP addresses.

A static IP address is an Internet address that a network administrator assigns exclusively to a system or a resource. The address assignment remains in effect until it is changed by the network administrator.

The IP address assignments for the cluster’s public LAN segments depend on the environment’s configuration. Configurations running the Windows operating system require static IP addresses assigned to hardware and software applications in the cluster, as listed in Table 2-1.

Table 2-1. Applications and Hardware Requiring IP Address Assignments

Application/Hardware Description

Cluster IP address The cluster IP address is used for cluster management and

must correspond to the cluster name. Because each server has at least two network adapters, the minimum number of static IP addresses required for a cluster configuration is five (one for each network adapter and one for the cluster). Additional IP addresses are required when WSFC is configured with application programs that require IP addresses, such as file sharing.

Cluster-aware applications running on the cluster

These applications include Microsoft SQL Server Enterprise Edition, Microsoft Exchange Server, and Internet Information Server (IIS). For example, SQL Server Enterprise Edition requires at least one static IP address for the virtual server as SQL Server does not use the cluster's IP address. Also, each IIS Virtual Root or IIS Server instance configured for failover needs a unique static IP address.

22 Preparing Your Systems for Clustering

Table 2-1. Applications and Hardware Requiring IP Address Assignments (continued)

Application/Hardware Description

Cluster node network adapters

For cluster operation, two network adapters are required: one for the public network (LAN/WAN) and another for the private network (sharing heartbeat information between the nodes).

For more information on cabling your cluster hardware and the storage array that you are using, see "

Hardware" in the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

Cabling Your Cluster

NOTE: To ensure operation during a DHCP server failure, use

static IP addresses.

Configuring IPv4 Addresses for Cluster Nodes

Use the static IP address assignments for the network adapters used for the cluster nodes.

NOTE: The IPv4 addresses in Table 2-2 are used as examples only.

Table 2-2. Examples of IP Address Assignments

Usage Cluster Node 1 Cluster Node 2

Public network static IP address (for client and domain controller communications)

Public network subnet mask 255.255.255.0 255.255.255.0

Default gateway

DNS servers

192.168.1.101 192.168.1.102

192.168.1.1 192.168.1.1

Primary

192.168.1.21

Secondary

192.168.1.22

Primary

192.168.1.21

Secondary

192.168.1.22

Preparing Your Systems for Clustering 23

Table 2-2. Examples of IP Address Assignments (continued)

Usage Cluster Node 1 Cluster Node 2

Private network static IP address cluster interconnect (for node-to-node communications)

Private network subnet mask 255.255.255.0 255.255.255.0

NOTE: Do not configure Default Gateway, NetBIOS, WINS, and DNS on the private

network.

10.0.0.1 10.0.0.2

If multiple cluster interconnect network adapters are connected to a network switch, ensure that all of the NICs configured for private network have a unique address. You can continue the IP address scheme in Table 2-2 with

10.0.0.3, 10.0.0.4, and so on for the NICs configured for the private network or NIC teams of the other clusters connected to the same switch.

You can improve fault tolerance by using network adapters that support adapter teaming or by having multiple LAN segments. To avoid communication problems, do not use dual-port NICs for the cluster interconnect.

NOTE: NIC teaming is supported only on a public network, not on a private

network.

Configuring IPv6 addresses for Cluster Nodes

Windows Server 2008 supports IPv6 and hence Failover Clustering also supports IPv6. Therefore, you can configure all IPv6 address resources, all IPv4 address resources, or a combination of IPv4 and IPv6 address resources.

Failover Clustering supports only IPv6 addresses that allow for dynamic registration in DNS (AAAA host records and the IP6.ARPA reverse look-up zone).

The left most bits of the IPv6 address are called the Format Prefix (FP), which indicates the specific type of IPv6 address. IPv6 accommodates many address type, including:

• Unicast addresses — Unicast addresses are used for one-to-one communication between two hosts.

• Multicast addresses — Multicast addresses are used for one-to-many communication. In Multicast addressing a single IP packet is sent to multiple hosts in a group.

24 Preparing Your Systems for Clustering

• Anycast addresses — Anycast addresses used for one-to-one-of-many communication. In Anycast addressing an IP packet is sent to the nearest member in a group.

Unicast Addresses have the following types:

Global unicast addresses — This address can be identified by format

001

prefix (FP) of

. The global unicast addresses are equivalent to public IPv4 addresses and can be used for Public Interfaces. They are globally routable and reachable on the IPv6 portion of Internet. The 128 bits of the unicast address space can be divided into three sections:

• Prefix — The network ID or prefix of the address, used for routing.

The first 48 bits are used for prefix.

• Subnet Identifier — A number that identifies a subnet within a site.

After the Prefix, 16 bits are used for Subnet ID.

• Interface ID — Unique identifier for a particular interface (host or

other device). This ID is unique within the specific prefix and subnet. After the Subnet ID, the 64 bits are used for Interface ID.

Link local addresses — Identified by format prefix (FP) of 1111 1110 10. These addresses are used by nodes when they are communicating with neighboring nodes on the same link. Dynamic registrations do not occur for link local addresses and therefore cannot be used in a cluster.

Site Local addresses — Identified by format prefix (FP) of 1111 1110 11. These addresses are equivalent to IPv4 private address space. Use these addresses between nodes that communicate with other nodes in the same site.

Creating Separate Subnets for the Public and Private Networks

The NICs that are configured for the public and private networks and are installed in the same cluster node must reside on separate IP subnetworks. Therefore, the private network used to exchange heartbeat information between the nodes must have a separate IP subnet or a different network ID than the public network, which is used for client connections.

Preparing Your Systems for Clustering 25

Configuring the Network Interface Binding Order for Clusters Running Windows Server 2008

After configuring the IP addresses for networks on your Failover Cluster, configure the Network Interface Binding Order:

Click

Start→

Control Panel→ double-click

In the

Ta s ks

pane, click the

The

Network Connections

Click the

The

In the

Advanced

Advanced Settings

menu and then click

window appears.

Adapters and Bindings

the top of the list followed by the

Manage Network Connections

window appears.

tab, ensure that the

Private

Network And Sharing Center

Advanced Settings

Public

connection is at

connection.

To change the connection order:

Click

Public

Private

Click the up-arrow or down-arrow to move the connection to the top or bottom of the

Click OK.

Close the

NOTE: If your cluster node has more network adapters other than the public

and private network adapters, they can be listed in any order, in the Adapters and Bindings tab, under the Private connection.

Connections

box.

Network Connections

window.

Dual-Port NICs and NIC Teaming in the Private Network

Dual-port NICs and NIC teaming are not supported in the private network. They are supported only in the public network.

Verifying Communications Between Nodes

Open a command prompt on each cluster node.

At the prompt, type:

ipconfig /all

Press <Enter>.

All known IP addresses for each local server appear on the screen.

Issue the

ping

26 Preparing Your Systems for Clustering

command from each remote system.

Ensure that each local server responds to the ping command. If the IP assignments are not set up correctly, the nodes may not be able to communicate with the domain. For more information on this issue, see "Troubleshooting" on page 5.

Installing the Storage Connection Ports and Drivers

Before you connect each cluster node to the shared storage:

• Ensure that an appropriate storage connection exists on the nodes.

• Ensure that the cluster nodes have a complementary technology that enables proper interaction between the nodes and shared Fibre Channel, SAS, or iSCSI storage array.

• You may also require operating system drivers and Multipath Input/Output (MPIO) drivers to ensure proper interaction between the cluster nodes and the shared storage array.

For more information, see "Preparing Your Systems for Clustering" in the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at

support.dell.com/manuals.

Installing and Configuring the Shared Storage System

The shared storage array consists of disk volumes that are used in your cluster. The storage management software for each supported shared storage array provides a way to create disk volumes and assigns these volumes to all the nodes in your cluster.

For more information, see the "Preparing Your Systems for Clustering" section in the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

Preparing Your Systems for Clustering 27

Configuring Hard Drive Letters When Using Multiple Shared Storage Systems

Before creating the cluster, ensure that both nodes have the same view of the shared storage systems. Because each node has access to hard drives that are in a common storage array, each node must have identical drive letters assigned to each hard drive. Using volume mount points in Windows Server 2008, your cluster can access more than 22 volumes.

NOTE: Drive letters A through D are reserved for the local system.

To ensure that hard drive letter assignments are identical:

Ensure that your cables are attached to the shared storage devices in the

proper sequence.

You can view all storage devices using the Windows Server 2008 Disk Management console.

To maintain proper drive letter assignments, ensure that each storage connection port on the storage device is enumerated by each node. Also, ensure that each storage connection port is connected to the same RAID controller, storage processor, or SAN switch.

For more information on the location of the RAID controllers or storage processors on your shared storage array, see "Cabling Your Cluster Hardware" in the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at

support.dell.com/manuals

Go to "Formatting and Assigning Drive Letters and Volume Labels to the Disks" on page 28.

Formatting and Assigning Drive Letters and Volume Labels to the Disks

Open

Disk Management

Ensure that the shared disks are letters and volume labels on node 1 by using the

Management

For example, create volumes labeled "Volume Y" for disk Y and "Volume Z" for disk Z.

28 Preparing Your Systems for Clustering

utility.

on the

Server Manager

Online

. Format the disks, assign the drive

Windows Disk

Perform the following steps on all the node(s):

Open

Disk Management

Assign the drive letters for the drives.

Reassign the drive letter, if necessary.

on the

Server Manager

To reassign the drive letter:

• With the mouse pointer on the same icon, right-click and select

Change Drive Letter and Path

• Click

Change

, select the letter you want to assign the drive

(for example, Z), and then click

Yes

• Click

to confirm the changes.

from the submenu.

If the cables are connected properly, the drive order is the same as is on each node, and the drive letter assignments of all the cluster nodes follow the same order as is on node 1. The volume labels can also be used to double-check the drive order by ensuring that the disk with volume label "Volume Z" is assigned to drive letter Z and so on for each disk on each node. Assign drive letters on each of the shared disks, even if the disk displays the drive letter correctly.

For more information about the storage array management software, see your storage array documentation located on the Dell Support website at support.dell.com/manuals.

Configuring Your Failover Cluster

The Failover Clustering feature included in Windows Server 2008 installs the Cluster Service. The Cluster Service performs the basic cluster functionality including membership, communication, and failover management.

NOTE: For installing and performing operations on Failover Clusters, you must be

logged on to the domain with an account that has local Administrator rights on all the systems that you want to configure as cluster nodes.

NOTE: Dell supports running Windows Server 2008 Failover Clustering in a non-

redundant configuration on Dell PowerVault MD3000 storage system using single port SAS controller only if the WS08clusprepcfg.xml file is installed. Ensure that this file is installed before you run the Validate a Configuration wizard. For more information on downloading the file, see the Dell Support site at support.dell.com/manuals.

Preparing Your Systems for Clustering 29

To install Failover Clustering feature:

Click

Start→

Administrative Tools→

Server Manager

, if

Server Manager

not running,

If prompted for permission to continue, click

Under

Features Summary

In the

Add Features

and then click

Click

Repeat the step 1 to step 5 for each system that you want to configure as

Install

to close the wizard.

, click

Add Features

Wizard, click

Failover Clustering and Multipath I/O

Continue

cluster node.

When you install Failover Clustering, the Cluster Service starts on each node and responds automatically if one of the nodes fails or goes offline. To provide application failover for the cluster, the Failover Clustering feature must be installed on each cluster node.

For more information, see "Understanding Your Failover Cluster" on page 5.

Validating Your Failover Cluster Configuration

NOTE: It is strongly recommended that you validate your configuration by running

all tests in the Validate a Configuration Wizard before you create a Failover Cluster. By running the tests, you can confirm that your hardware and settings are compatible with Failover Clustering. You can run the tests on a set of systems and storage devices either before or after you have configured them in a Failover Cluster. Dell and Microsoft support a cluster configuration as long as it has passed all the tests included in Validate a Configuration Wizard.

To run Validate a Configuration wizard:

After you have installed Failover Clustering Feature on all your nodes,

connected your storage and configured drive letters and volumes, open the Failover Cluster MMC from

Cluster Management.

Go to the

Click

Action

and on the

tab and select

names of the systems that you want to be a part of your cluster and click

Add

. Click

Start→

Administrative Tools→

Validate a Configuration Wizard

Select Servers or a Cluster

Failover

window. Enter the

30 Preparing Your Systems for Clustering

On the or select

On the last screen of the confirm.

This runs a list of validation tests and prompt the errors or warnings that are present in the configuration in the form of a

Testing Options

Run all tests

(recommended).

window, select the specific tests you want to run

Validate a Configuration

wizard, click

Summary

window.

Configuring Windows Server 2008 Failover Clustering

The cluster setup files are installed on the system disk when you add Failover Clustering feature from the Add Feature wizard. To configure the Failover

Cluster feature in Windows Server 2008:

In the Failover Cluster Management console, select

Management

Follow the instructions in the wizard, and click

To view a report of the tasks that the wizard performed, Click

, under

Management

option, click

Failover Cluster

Create a Cluster

Finish

View Report

Adding a Cluster Node to the Failover Cluster

To add a cluster node:

Turn on the node(s).

Run the node(s).

If the cluster you want to configure is not displayed in the console tree of the

Management

that you want to configure.

Click to complete the process.

Validate a Configuration

Failover Cluster Management

, click

Manage a Cluster

Add Node

in the

Actions

pane. Follow the instructions on the screen

on the new node along with the existing

screen, right-click

, and select or specify the cluster

Failover Cluster

Preparing Your Systems for Clustering 31

Configuring the Quorum Disk in Failover Clustering

The Quorum configuration determines the maximum number of failures a Failover Cluster can sustain without stopping the Cluster Service. In your cluster configured with the Windows Server 2008 operating system, you do not have to configure a shared storage resource for the Quorum disk. The following terms are commonly used in the concept of Quorum resource in the Windows Server 2008 operating system:

• The Quorum disk in the Failover Cluster must have the majority of nodes in the cluster

• Depending on the quorum configuration you select, the term refer to the failure of a node, failure of a disk designated as the the failure of a file share designated as the

witness

Failover clustering provides the following four options for quorum configuration:

Node and Disk Majority

shared storage that is designated as a

- The cluster nodes, along with a disk resource on

witness

, are given one vote each. The cluster is online even if half of the total number of nodes rounded up are alive and the witness disk is online. If the witness disk fails, the cluster can sustain the failure of one node less than half of the total number of nodes rounded up.

If N denotes the number of nodes in your cluster which have one vote each and one vote is allotted to the witness disk, then, the total number of votes for the cluster to be up:

votes

from a

failure

may

witness

, or

{N+1 (witness disk) +1}/2

NOTE: If your cluster has odd number of Cluster Nodes, truncate the decimal

output to the next whole number. For example, if your cluster has 5 nodes, then the total number of votes for the cluster is 5+1+1= 7/2 = 3.5. Round off 3.5 to next whole number which is 4. Therefore, the total number of votes required for the cluster to be online is 4.

Node and File Share Majority

- This model is similar to Node and Disk Majority in behavior but the witness disk is replaced by a File share to act as the witness. You can configure the File Share Witness as any network share that is accessible by all the cluster nodes.

32 Preparing Your Systems for Clustering

Node Majority

: The cluster nodes determine the maximum number of failures that the cluster can sustain (similar to the Majority Node Set feature in the Windows Server 2003 operating system). A Node Majority Cluster can sustain the failure of one node less than half the total number of nodes rounded up in the cluster.

No Majority - Disk only

: This model cannot sustain the failure of the quorum disk (similar to the Shared Disk Quorum feature in the Windows Server 2003 operating system), which becomes a single point of failure, and is therefore not recommended.

NOTE: It is recommended that you use Node and Disk Majority option for quorum

configurations.

NOTE: If your cluster setup has odd number of nodes while creating the Failover

Cluster then WSFC uses Node Majority quorum model. You can manually change the quorum model to Node and Disk Majority.

Creating a LUN for the Witness Disk for Node and Disk Majority and No Majority Models

NOTE: It is recommended that you create a separate LUN of 512 MB (approximately)

for the witness disk for the Node and Disk Majority and No Majority quorum models. The witness disk in these models has a copy of the cluster configuration.

When you create the LUN for the witness disk on the shared storage ensure that you have:

• Formatted the LUN with NTFS.

• Used the LUN exclusively for the Cluster logs.

• Not stored any application data or user data on the witness disk.

NOTE: It is recommended that you use a RAID level other than RAID 0, which is

commonly called striping. RAID 0 configurations provide very high performance, but they do not provide the level of availability required for the witness disk.

Configuring a Service or Application for High Availability

Failover Clustering in Windows Server 2008 allows you to configure a service or an application for high availability by running the Configure a Service or Application for High Availability wizard. To configure a highly-available service or application:

Preparing Your Systems for Clustering 33

In the

Failover Cluster Management

Cluster Management,

cluster you want to configure.

Click

Services and Applications

Application

Follow the instructions in the wizard to specify the service or application that you want to configure for high availability. When prompted, enter the following information:

• A name for the clustered service or application. This name is registered in DNS and associated with the IP address for this clustered service or application.

• Any IP address information that is not automatically supplied by your DHCP settings.

• The storage volume or volumes that the clustered service or application should use.

• Any specific information for the service or application that you are configuring.

Click

under

View Report

click

Manage a Cluster

Actions

if you want to see the report for the tasks performed.

console, right-click on

, and select or specify the

and click

Configure a Service or

Failover

Verifying Failover of a Clustered Service or Application

After you have configured a service or application for high availability using the instructions above, you can verify the failover of the clustered service or application:

In the

Failover Cluster Management

Cluster Management,

cluster you want to configure.

Under

Services and Applications

which you want to test failover.

Under

Actions,

Check if the service or application comes online on the other node.

click

Manage a Cluster

Move

this service or application to another node.

console, right-click on

, and select or specify the

, click on the service or application for

Failover

34 Preparing Your Systems for Clustering

Modifying Properties of a Clustered Service or Application

Failover Clustering allows you to modify the failover behavior of a clustered service or application. To modify the clustered service properties:

Right-click on the clustered service or application and click on

Select from the two tabs available under these tabs:

•

Preferred owners

allows you to designate one or more nodes in your cluster as the Preferred Owner for the clustered service or application. It also allows you to set the order of nodes.

•

Prevent Failback/Allow Failback

tab. This option enables you to specify if the service or application automatically fails back to the most preferred owner.

•

Maximum failures in the specified period and Period (hours)

is an option under number of times the cluster service must attempt to restart or failover the service or application in a specified time period. If the service or application fails more than the maximum limit specified, the service or application is left in the failed state.

General

- This is an option under

Failover

and

Failover

- This is an option under

tab. This option enables you to specify the

. The following options

General

Properties

tab. This option

General

- This

Preparing Your Systems for Clustering 35

36 Preparing Your Systems for Clustering

Installing Your Cluster Management Software

This section provides information on configuring and administering your cluster using Microsoft

Failover Cluster Management console.

Microsoft Failover Cluster Management Console

Failover Cluster Management console is Microsoft's tool for configuring and administering a cluster. The following sections describe the procedures to run Failover Cluster Management console locally on a cluster node and to install the tool on a remote console. To launch the Failover Cluster Management console, click Start Management

Running Failover Cluster Management on a Remote Console

You can administer and monitor the Cluster Service remotely by installing the Remote Server Administration Tools (RSAT) and Failover Clustering feature on a remote console (or management station) running the Microsoft Windows

The RSAT tool for Failover Clustering includes the Failover Cluster Manager console and the cluster.exe command line tool.

To install Remote Server Administration Tools package on a remote console:

On a system running any Windows operating system that you want to configure as the remote console:

Click

Start→

→ Programs→ Administrative Tools→ Failover Cluster

operating system.

Server Manager→

Features→

Add Features

Expand the

Feature Administration Tools

Select

Click

After a few minutes, the successfully installed.

Remote Server Administration Tools

Failover Clustering Tools

Install

tab and then expand the

option and click

Remote Server Administration Tools package

Installing Your Cluster Management Software 37

Launching Failover Cluster Management Console on a Remote Console

Perform the following steps on the remote console:

Ensure that the system.

Click

Start

Select

Failover Cluster Management

Click

Action

Provide the name of the cluster you want to manage and click

Failover Clustering Tools

and select

tab in the console and select

Administrative Tools

is installed from RSAT on the

Manage a Cluster

option.

OK.

38 Installing Your Cluster Management Software

Understanding Your Failover Cluster

Cluster Objects

Cluster objects are the physical and logical units managed by a cluster. Each object is associated with the following:

• Properties that define the object and its behavior within the cluster

• A set of cluster control codes used to manipulate the object's properties

• A set of object management functions to manage the object through Microsoft

Cluster Networks

A cluster network provides a communications link between the cluster nodes (private network), the client systems in a local area network (public network), or a combination of the above (public-and-private network).

Preventing Network Failure

When you install the Failover Clustering feature provided by the Microsoft Windows Server 2008 operating system, identify the public and private network segments connected to your cluster nodes. To ensure cluster failover and non-interrupted communications, perform the following procedures:

• Configure the private network for internal communications.

• Configure the public network for all communications to provide a redundant path if all of the private networks fail.

• Configure subsequent network adapters for client system use only or for all communications.

You can set priorities and roles of the networks when you install the Failover Clustering feature.

Windows Server® 2008 Failover Cluster (

WSFC).

Understanding Your Failover Cluster 39

Network Interfaces

You can use the Failover Cluster Management console to view the state of all cluster network interfaces.

Cluster Nodes

A cluster node is a system in a cluster running the Microsoft Windows® operating system and WSFC.

Each node in a cluster:

• Attaches to one or more cluster storage devices

• Communicates with the other nodes through network adapters

• Is aware of systems that join or leave the cluster

• Is aware of the resources that are running on each node

• Is grouped with the remaining nodes under a common cluster name, which is used to access and manage the cluster

Table 4-1 defines states of a node during cluster operation.

Table 4-1. Node States and Definitions

State Definition

Down The node is not actively participating in cluster operations.

Joining The node is becoming an active participant in the cluster operations.

Paused The node is actively participating in cluster operations but cannot take

ownership of resource groups or bring resources online.

Up The node is actively participating in all cluster operations, including

hosting cluster groups.

Unknown The node state cannot be determined.

When Failover Clustering is configured on a node, the administrator chooses whether that node forms its own cluster or joins an existing cluster. When the cluster service is started, the node searches for other active nodes on networks that are enabled for internal cluster communications.

40 Understanding Your Failover Cluster

Forming a New Cluster

Failover Clustering maintains a current copy of the cluster database on all active nodes. If a node cannot join a cluster, the node attempts to gain control of the witness disk resource in Node and Disk Majority model and forms a cluster. The node uses the recovery logs in the quorum resource to update its cluster database.

Joining an Existing Cluster

A node can join a cluster if it can communicate with another active node in the cluster. When a node joins a cluster, the node is updated with the latest copy of the cluster database. Failover Clustering validates the node's name, verifies version compatibility, and the node joins the cluster.

Cluster Resources

A cluster resource is any physical or logical component that can be:

• Brought online and taken offline

• Managed in a cluster

• Hosted by one managed system at a time

Setting Resource Properties

Failover Clustering allows you to set the properties for any resource that is a part of the cluster.

To change or modify resource properties:

Right-click the resource you want to modify and click on resource properties are listed under four tabs:

•

General

to stop using a failed disk and assign a different disk.

•

Dependencies

when bringing resources online and offline.

For example, if a group with a physical disk and a file share is brought online together, the physical disk containing the file share must be brought online before the file share. Under the can specify the resources that must be brought online before your resource can come online. You can add multiple dependencies using

- Allows you to rename the resource or use the

- Failover Clustering uses the resource dependencies list

Properties

Repair

Dependencies

. The

option

tab, you

Understanding Your Failover Cluster 41

AND or OR. If you use AND, all the dependent resources must come online before your resource can come online. If you use OR, any one of the dependent resources must be online before your resource can come online.

•

Policies

- Allows you to define your desired response to a failure of your resource. You can also specify the Pending time-out value here which is the length of time your resource can take to change states between online and offline before the Cluster Service puts it in a

•

Advanced Policies

- Allows you to select the possible nodes that can

Failed

state.

own the resource. The cluster also checks the health of the resource using either basic health check or thorough health check. You can define the

resource health check interval

Basic resource health check interval

Advanced Policies

and

Thorough

window.

Resource Dependencies

Failover Clustering uses the Resource Dependencies list when bringing resources online and offline. For example, if a group with a physical disk and a file share is brought online together, the physical disk containing the file share must be brought online before the file share. Table 4-2 shows resources and their dependencies.

Table 4-2. Cluster Resources and Required Dependencies

Resource Required Dependencies

File share Network name (only if configured as a distributed file system

[DFS] root)

IP address None

Network name IP address that corresponds to the network name

Physical disk None

42 Understanding Your Failover Cluster

A dependent resource requires another resource to operate. Table 4-3 describes resource dependencies.

Table 4-3. Resource Dependencies

Term Definition

Dependent resource

Dependency A resource on which another resource depends.

Dependency tree A series of dependency relationships or hierarchy.

A resource that depends on other resources.

The following rules apply to a dependency tree:

• A dependent resource and its dependencies must be in the same group.

• A dependent resource is taken offline before its dependencies and brought online after its dependencies, as determined by the dependency hierarchy.

Creating a Resource

Open the Failover Clustering console, right-click on the resource that you want to modify, and click

Under the

Dependencies

Properties

tab, you can specify the resources that must be brought online before your resource can come online. You can add multiple dependencies using AND or OR.

If you use AND, all the dependent resources must come online before your resource can come online. If you use OR, any one of the dependent resources must come online before your resource can come online.

To view the and select the

NOTE: You must configure the required dependencies before you create the

resource.

Resource Dependency

Show Dependency Report

Understanding Your Failover Cluster 43

diagram, right-click on the resource

option.

Resource Failure

Failover Clustering periodically checks if a resource is functioning properly using either basic health check or thorough health check.

In the Failover Clustering console, right-click on the resource you want to modify, and click

Under the

check interval

The Thorough resource health check interval requests a more thorough check of the resource's state and therefore is typically longer than the Basic resource health check interval.

NOTE: Do not adjust the Basic resource health check interval and Through resource

health check interval settings unless instructed to do so by Dell Technical Support.

Adjusting the Resource Failure Policies

To define your desired response to a failure of your resource:

Right-click on the resource and click

In the Policies tab you can specify the

Pending time-out value is the length of time your resource can take to change states between online and offline before the Cluster Service puts it in a

Failed

Additionally you can set the following failure policies:

• If the resource fails, you can choose not to restart the resource on the current node or attempt restart on the current node. You can specify the

period for restarts

• If restart is unsuccessful, you can choose to failover all resources along with their dependent resources.

• If the cluster service exceeds the maximum number of restart attempts within the specified time period and the failed resource has not been restarted, Failover Clustering considers the resource to be failed.

Properties

Advanced Policies

and

Thorough resource health check interval

state.

and the

maximum restarts

tab, you can define the

Properties

and click the

Pending time-out

in the specified time period.

Basic resource health

Policies

tab.

value.

NOTE: To configure the Looks Alive, Is Alive, Threshold, and Period values for a

particular resource, see "Setting Resource Properties" on page 7.

NOTE: Do not adjust the Basic resource health check interval and Through resource

health check interval settings unless instructed to do so by Dell technical Support.

44 Understanding Your Failover Cluster

Replacing a Failed Disk

If a disk in a Failover Cluster has failed, you can assign a different disk. To replace the failed disk:

Right-click on the resource and click

In the

General

use. The new disk that you assign must be one that can be clustered.

NOTE: The Repair option does not recover data. You can restore data to the disk

before using the Repair option.

File Share Resource Type

If you want to use your cluster solution as a high-availability file server, select one of the following types of file share for your resource:

• Basic file share — Publishes a file folder to the network under a single name.

• Share subdirectories — Publishes several network names-one for each file folder and all of its immediate subfolders. This method is an efficient way to create large numbers of related file shares on a file server.

• DFS root — Creates a resource that manages a stand-alone DFS root. Fault-tolerant DFS roots cannot be managed by this resource. A DFS root file share resource has required dependencies on a network name and an IP address. The network name can be either the cluster name or any other network name for a virtual server.

tab, click

Repair,

Properties

and select a new disk that you want to

Configuring Active and Passive Cluster Nodes

Active nodes process application requests and provide client services. Passive nodes are backup nodes that ensure that client applications and services are available if a hardware or software failure occurs. Cluster configurations may include both active and passive nodes.

NOTE: Passive nodes must be configured with appropriate processing power and

storage capacity to support the resources that are running on the active nodes.

Your cluster solution supports variations of active/active and active/passive configurations.

Cluster solutions running the Windows Server 2008 operating system can support up to sixteen nodes in multiple configurations.

Understanding Your Failover Cluster 45

An active/active configuration contains virtual servers running separate applications or services on each node. When an application is running on node 1, the remaining node(s) do not have to wait for node 1 to fail. Those node(s) can run their own cluster-aware applications (or another instance of the same application) while providing failover for the resources on node 1. For example, multiway failover is an active/active failover solution because running applications from a failed node can migrate to multiple active nodes in the cluster. However, you must ensure that adequate resources are available on each node to handle the increased load if one node fails.

In an active/passive configuration, one or more active cluster nodes are processing requests for a clustered application while the passive cluster nodes only wait for the active node(s) to fail.

Failover Policies

When implementing a failover policy, configure failback if the cluster node lacks the resources (such as memory or processing power) to support cluster node failures.

Windows Server 2008 Cluster Configurations

Cluster configurations running Windows Server 2008 provide the following failover policies:

•

(number of active nodes)+ I (number of inactive nodes) failover

• Failover pair

• Multiway failover

• Failover ring

Table 4-4 provides an overview of the failover policies implemented with Windows Server 2008. For more information, see the sections that follow this table.

46 Understanding Your Failover Cluster

Table 4-4. Windows Server 2008 Failover Policies

Failover Policy

N + I One or more nodes

Failover pair Applications can

Multiway Running applications

Failover ring Running applications

Description Advantage Disadvantage(s)

• May not handle more than one backup node failure.

• May not fully utilize all of the nodes.

Applications on the pair cannot tolerate two node failures.

Must ensure that the failover nodes have ample resources available to handle the additional workload.

The next node for failover may not have ample resources to handle the workload.

provides backup for multiple systems.

failover between the two nodes.

migrate to multiple nodes in the cluster.

migrate to the next preassigned node.

Highest resource availability.

Easy to plan the capacity of each node.

Application load-balancing.

Easy to scope node capacity for one server failure.

N + I Failover

N + I failover is an active/passive policy where dedicated passive cluster node(s) provide backup for the active cluster node(s). This solution is best for critical applications that require dedicated resources. However, backup nodes add a higher cost of ownership because they remain idle and do not provide the cluster with additional network resources.

Figure 4-1 shows an example of a 6 + 2 (N + I) failover configuration with six active nodes and two passive nodes. Table 4-5 provides an N + I failover matrix for Figure 4-1.

Understanding Your Failover Cluster 47

Figure 4-1. Example of an N+I Failover Configuration for an Eight-Node Cluster

cluster node 3

cluster node 4

cluster node 5

cluster node 8 (backup)

cluster node 1

cluster node 2

cluster node 6

cluster node 7 (backup)

Table 4-5. Example of an N+I Failover Configuration for an Eight-Node Cluster

Cluster Resource Group Primary Node AntiAffinityClassNames Value

A Node 1 AString

B Node 2 AString

C Node 3 AString

D Node 4 AString

E Node 5 AString

F Node 6 AString

48 Understanding Your Failover Cluster

Configuring Group Affinity

On N + I (active/passive) Failover Clusters running Windows Server 2008, some resource groups may conflict with other groups if they are running on the same node. For example, running more than one Microsoft Exchange virtual server on the same node may generate application conflicts. Use Windows Server 2008 to assign a public property (or attribute) to a dependency between groups to ensure that they failover to similar or separate nodes. This property is called group affinity.

Group affinity uses the AntiAffinityClassNames public property, which ensures that designated resources are running on separate nodes, if possible.

For example, in Table 4-5, the AntiAffinityClassNames string for cluster resource group A and group B are identical (AString), which indicates that these groups are assigned to run on separate nodes, if possible. If node 1 fails, resource group A fails over to the next backup node (node 7). If node 2 then fails, because their AntiAffinityClassNames string value (AString) identifies group A and group B as conflicting groups, group B skips node 7 and instead fails over to node 8.

To set the public property for the cluster groups shown in Table 4-5:

Open a command prompt.

Type the following:

cluster group "A" /prop AntiAffinityClassNames= "AString"

Repeat step 2 for the remaining cluster groups.

To specify group affinity in your N + I cluster configuration, use the Cluster Data Form in the Dell Failover Cluster Hardware Installation and

Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com.

Failover Pair

Failover pair is a policy in which each application can failover between two specific nodes in a multinode cluster. The Possible Owners list in Cluster Administrator determines which nodes run the failed over applications.

Understanding Your Failover Cluster 49

If you have applications that run well on two-node cluster, and you want to

cluster node 1

cluster node 2

cluster node 3

cluster node 4

application A

application B

migrate these applications to Windows Server 2008, failover pair is a good policy. This solution is easy to plan and administer, and applications that do not run well on the same server can easily be moved into separate failover pairs. However, in a failover pair, applications on the pair cannot tolerate two node failures.

Figure 4-2 shows an example of a failover pair configuration. Table 4-6 provides a failover configuration for the cluster shown in Figure 4-2.

Figure 4-2. Example of a Failover Pair Configuration

Table 4-6. Example of a Failover Pair Configuration for a Four-Node Cluster

Cluster Resource Group Possible Owners List

App1 1, 2

App2 3, 4

Multiway Failover

Multiway failover is an active/active policy where running applications from a failed node migrate to multiple nodes in the cluster. This solution provides automatic failover and load-balancing. Ensure that the failover nodes have sufficient resources to handle the workload. Figure 4-3 shows an example of four-node multiway failover configuration.

50 Understanding Your Failover Cluster

Table 4-7 shows a four-node multiway failover configuration for the cluster

cluster node 1

cluster node 2

cluster node 4 cluster node 3

application A

application B

application C

shown in Figure 4-3. For each resource group, the failover order in the Preferred Owners list in Failover Cluster Management console outlines the order that you want that resource group to failover. In this example, node 1 owns applications A, B, and C. If node 1 fails, applications A, B, and C failover to cluster nodes 2, 3, and 4. Configure the applications similarly on nodes 2, 3, and 4.

When implementing multiway failover, configure failback to avoid performance degradation. See "Understanding Your Failover Cluster" on page 5 for more information.

Figure 4-3. Example of a Four-Node Multiway Failover Configuration

Table 4-7. Example of a Four-Node Multiway Failover Configuration

Application Failover Order in the Preferred

Owners List

ANode 2

BNode 3

CNode 4

Understanding Your Failover Cluster 51

Failover Ring

application A

application C

application Bapplication D

Failover ring is an active/active policy where all running applications migrate from the failed node to the next preassigned node in the Preferred Owners List. If the failing node is the last node in the list, the failed node’s applications failover to the first node.

While this type of failover provides high availability, ensure that the next node for failover has sufficient resources to handle the additional workload.

Figure 4-4 shows an example of a failover ring configuration.

Figure 4-4. Example of a Four-Node Failover Ring Configuration

Failover and Failback Capabilities

Failover

When an application or cluster resource fails, WSFC detects the failure and attempts to restart the resource. If the restart fails, WSFC takes the application offline, moves the application and its resources to another node, and restarts the application on the other node.

See "Setting Resource Properties" on page 7 for more information.

Cluster resources are placed in a group so that WSFC can move the resources as a combined unit, ensuring that the failover and/or failback procedures transfer all resources.

After failover, Cluster Administrator resets the following recovery policies:

• Application dependencies

• Application restart on the same node

• Workload rebalancing (or failback) when a failed node is repaired and brought back online

52 Understanding Your Failover Cluster

Failback

Failback returns the resources back to their original node. When the system administrator repairs and restarts the failed node, WSFC takes the running application and its resources offline, moves them from the Failover Cluster node to the original node, and then restarts the application.

You can configure failback to occur immediately, at any given time, or not at all. To minimize the delay until the resources come back online, configure the failback time during off-peak hours.

Modifying Your Failover Policy

Use the following guidelines when you modify your failover policy:

• Define how Failover Clustering detects and responds to group resource failures.

• Establish dependency relationships between the resources to control the order in which the resources are taken offline.

• Specify time-out, failover threshold, and failover period for your cluster resources.

See "Resource Failure" on page 10 for more information.

• Specify a

Possible Owner List

in Failover Clustering MMC for cluster resources. The Possible Owner List for a resource controls which nodes are allowed to host the resource.

Understanding Your Failover Cluster 53

54 Understanding Your Failover Cluster

Maintaining Your Cluster

This section provides instructions to perform multiple maintenance tasks like adding, configuring, and removing cluster components in your Dell™ Failover Cluster.

Adding a storage to a Failover Cluster Node

Failover Clustering groups all available disks on the shared storage into a group named Available Storage group. You can also add storage to an existing Failover Cluster. To add storage to an existing Failover Cluster:

Open the Failover Cluster Management console and connect to your cluster.

Right-click on all the cluster nodes and can be clustered is listed.

Select the disks you want to add and then click OK.

This adds the disk to the Available Storage group of your Failover Cluster.

Configuring Network Settings of a Failover Cluster Node

The cluster nodes should have at least two networks, one for private network traffic and one for public network traffic. Failover Clustering allows you to specify if a network will be used by the cluster, either by the nodes only or by nodes and clients, or not used by the cluster at all. It is a generally accepted practice to enable your private network for use by the cluster nodes only and your public network to be used by cluster nodes and clients connected to the cluster.

To configure the network settings of a Failover Cluster:

Open the cluster.

Expand click

Modify

Storage

and click

Failover Cluster Management

Networks

, right-click the network that you want to configure, and

Add a Disk

. Any disks that are visible from

console and connect to your

Maintaining Your Cluster 55

Configure the networks:

• For your Private network, select .

only

• For your Public network, select both

network

• For any other network such as iSCSI network that might be

configured, select

and

Allow clients to connect through this network

Do not allow the cluster to use this network

Allow the cluster to use this network

Allow the cluster to use this

Maintaining a Clustered Service or Application

You can take any of your clustered service or applications offline to perform maintenance or diagnostics. The cluster service ensures that all the dependencies are met before making a clustered service or application Online or Offline.

To bring a Clustered service or application Online or Offline:

To open the Failover Cluster Management console, click

Administrative Tools

Under

Services and Applications

you want to take online or offline.

Right-click on the service or application and select from the following option:

•

Bring this service or application online

• Take this service or application offline

, navigate to the service or application

Start→

NOTE: To monitor the events for the service or application, right-click on a service

or application, select the Show the critical events for this application. A list of critical errors that have occurred on this service or application is displayed.

Starting or Stopping Cluster Service on Cluster Nodes

Failover Clustering allows you to stop and restart the Cluster Service on a node for troubleshooting or maintenance operations on the node. All applications or services hosted on that node fails to the other node when you stop the cluster service.

56 Maintaining Your Cluster

To stop or restart the cluster service on a node:

Right-click the node that you want to stop or restart in the

Cluster Management

Click

More Actions

displayed:

• Stop Cluster Service

•

Start Cluster Service

console.

and select from either of the following options that are

Failover

Running chkdsk on a Clustered Disk in Maintenance Mode

Failover Clustering allows you to put a disk in Maintenance mode without taking the disk offline. The health monitoring on the disk turns off for a period of time while maintenance is carried out on the disk. You can then run chkdsk utility on the disk.

To put a disk in Maintenance mode:

To open the

Administrative Tools

Right-click the disk that you want to put on maintenance mode.

Click option.

Ensure that the status of the disk is listed as the MMC.

Run

chkdsk

Failover Cluster Management

More Actions

utility on the disk.

and select

console, click

Turn On Maintenance Mode for this disk

Online (Maintenance)

Start→

Displaying Event Logs for a Failover Cluster

All cluster events can be viewed using the Failover Cluster Management console for any node in your Failover Cluster. To display the event logs:

To open the

Administrative Tools

In the console tree, right-click

Failover Cluster Management

Cluster Events,

Maintaining Your Cluster 57

console, click

and then click

Start→

Query

In the

Cluster Events Filter

events that you want to display and click

To view an event, click on the event, and see the details in the

Details

screen.

If you want the cluster logs to be displayed in textual format, then run the following command in the command prompt of each node:

cluster log /g.

You must be logged in as an Administrator to run the command.

dialog window, select the criteria for the

Event

58 Maintaining Your Cluster

Upgrading to a Cluster Configuration

This section provides instructions to perform upgrading a cluster configuration in your Dell™ Failover Cluster.

Before You Begin

Before you upgrade your non-clustered system to a cluster solution:

• Back up your data.

• Verify that your hardware and storage systems meet the minimum system requirements for a cluster as described in "System Requirements" on page 10.

• Verify that your hardware and storage systems are installed and configured as explained in the following sections:

–

Cabling Your Cluster Hardware

Hardware Installation and Troubleshooting Guide for the specific storage array

– "Preparing Your Systems for Clustering" on page 15

– "Installing Your Cluster Management Software" on page 5

section of the Dell Failover Cluster

Supported Cluster Configurations

Dell certifies and supports only solutions that are configured with the Dell products described in this guide. For more information on the corresponding supported adapters and driver versions, see Dell Cluster Configuration Support Matrices located on the Dell High Availability website at www.dell.com/ha.

Upgrading to a Cluster Configuration 59

Completing the Upgrade

After installing the required hardware and network adapter upgrades, set up and cable the system hardware.

NOTE: You may need to reconfigure your switch or storage groups so that both

nodes in the cluster can access their logical unit numbers (LUNs).

The final phase for upgrading to a cluster solution is to install and configure Microsoft

Windows Server® 2008 with WSFC.

60 Upgrading to a Cluster Configuration

Troubleshooting

This appendix provides troubleshooting information for your cluster configuration.

Table A-1 describes general cluster problems you may encounter and the probable causes and solutions for each problem.

Table A-1. General Cluster Troubleshooting

Problem Probable Cause Corrective Action

The nodes cannot access the storage system, or the cluster software is not functioning with the storage system.

The storage system is not cabled properly to the nodes or the cabling between the storage components is incorrect.

One of the cables is faulty.

You are using iSCSI storage array, the challenge handshake authentication protocol (CHAP) password entered is wrong.

You are using a Dell™ PowerVault™ MD3000 or PowerVault MD3000i storage array and the Host Group or Hostto Virtual Disk Mappings is not correctly created.

Ensure that the cables are connected properly from the node to the storage system. For more information, see the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at support.dell.com/manuals.

Replace the faulty cable.

Enter correct user-name and password for CHAP, if used.

Verify the following:

• Host Group is created and the cluster nodes are added to the Host Group.

• Host-to-Virtual Disk Mapping is created and the virtual disks are assigned to the Host Group containing the cluster nodes.

Troubleshooting 61

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

The nodes cannot access the storage system, or the cluster software is not functioning with the storage system.

You are using a Dell/EMC storage array and Access control is not enabled correctly.

You are using a Fibre Channel storage array in a Storage Area Network (SAN), and one or more zones are not configured correctly.

You are using a Fibre Channel storage array and the length of the interface cables exceeds the maximum allowable length.

Verify the following:

•EMC® Access Logix™ software is enabled on the storage system.

• All logical unit numbers (LUNs) and hosts are assigned to the proper storage groups.

Verify the following:

• Each zone contains only one initiator (Fibre Channel daughter card).

• Each zone contains the correct initiator and the correct storage port(s).

Ensure that the fibre optic cables do not exceed 300 m (for multimode) or 10 km (for single mode switch-to-switch connections only).

62 Troubleshooting

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

One of the nodes takes a long time to join the cluster.

One of the nodes fail to join the cluster.

The node-to-node network has failed due to a cabling or hardware failure.

Long delays in node-to-node communications may be normal.

Check the network cabling. Ensure that the node-to-node interconnection and the public network are connected to the correct NICs.

Verify that the nodes can communicate with each other by running the ping command from each node to the other node. Try both the host name and IP address when using the ping command.

One or more nodes may have the Internet Connection Firewall enabled, blocking Remote Procedure Call (RPC)

Configure the Internet Connection Firewall to allow communications that are required by the Microsoft Server 2008

Failover Cluster (WSFC) and the clustered applications or services.

communications between the nodes.

Troubleshooting 63

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

Attempts to connect to a cluster using Cluster Administrator fail.

You are prompted to configure one network instead of two during WSFC installation.

• The Cluster Service has not been started.

• A cluster has not been formed on the system.

• The system has just been booted and services are still starting.

The cluster network name is not responding on the network because the Internet Connection Firewall is enabled on one or more nodes.

The TCP/IP configuration is incorrect.

The private (point-topoint) network is disconnected.

Verify that the Cluster Service is running and that a cluster has been formed. Use the Event Viewer and look for the following events logged by the Cluster Service:

Microsoft Cluster Service successfully formed a cluster on this node.

Microsoft Cluster Service successfully joined the cluster.

If these events do not appear in Event Viewer, see the Microsoft Cluster Service Administrator’s Guide for instructions on setting up the cluster on your system and starting the Cluster Service.

Configure the Internet Connection Firewall to allow communications that are required by WSFC and the clustered applications or services.

The node-to-node network and public network must be assigned static IP addresses on different subnets. See "Assigning Static IP Addresses to Cluster Resources and Components" on page 22 for information about assigning the network IPs.

Ensure that all systems are powered on so that the NICs in the private network are available.

64 Troubleshooting

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

Unable to add a node to the cluster.

The disks on the shared cluster storage appear offline in Windows Disk Administration

The Validate Network Communication test fails on the iSCSI networks

The new node cannot access the shared disks. The shared disks are enumerated by the operating system differently on the cluster nodes.

One or more nodes may have the Internet Connection Firewall enabled, blocking RPC communications between the nodes.

This situation is normal. By default, the shared disks are offline when the node detects them the first time.

This is a known issue which occurs when you run Cluster Validation on a cluster configuration that is using iSCSI array as Direct attached storage in Windows Server 2008.

Ensure that the new cluster node can enumerate the cluster disks using Windows Disk Administration. If the disks do not appear in Disk Administration, check the following:

• Check all cable connections

• For Fibre Channel storage arrays, check all zone configurations

• Check the Access Control settings on the attached storage systems. Verify that the node in question is a member of the correct Storage Group or Host Group.

•Use the

Minimum

Configure the Internet Connection Firewall to allow communications that are required by the WSFC and the clustered applications or services.

Right-click on the disk and click Online.

See Microsoft Knowledge Base article KB951434 at the Microsoft Support website at support.microsoft.com for more information.

Advanced with

option

Troubleshooting 65

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

Cluster Services may not operate correctly on a cluster running Windows Server 2008 when the Internet Firewall enabled.

The Windows Internet Connection Firewall is enabled, which may conflict with Cluster Services.

Perform the following steps:

On the Windows desktop, right-

My Computer

click

Manage

In the

Computer Management

window, double-click

In the

Services

Cluster Services

click

In the

Cluster Services

click the

Click the

Recovery

First Failure

arrow and select

Service

Click the

Second Failure

down arrow and select service.

Click OK.

Public network clients cannot access the applications or services that are provided by the cluster.

One or more nodes may have the Internet Connection Firewall enabled, blocking RPC communications between the nodes.

Configure the Internet Connection Firewall to allow communications that are required by the WSFC and the clustered applications or services.

and click

Services

window, double-

window,

tab.

drop-down

Restart the

drop-

Restart

the

66 Troubleshooting

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

You are using a PowerVault MD3000 or PowerVault MD3000i storage array and Virtual Disks failover continuously between the two storage controllers when a storage path fails.

You are using a PowerVault MD3000 or PowerVault MD3000i storage array and Virtual Disk Copy operation fails.

The failback mode for the cluster node(s) is not set properly.

The Virtual Disk Copy operation uses the cluster disk as the source disk.

Set the correct failback mode on each cluster node:

• For PowerVault MD3000 storage, merge the in the PowerVault MD3000 Resource Media into the registry of each node. This file changes the PowerVault MD3000 from

Alone

• For PowerVault MD3000i, merge the

windows\utility

Dell PowerVault MD3000i resource media into the registry of each node. This file changes the PowerVault MD3000i from

Alone

To perform a Virtual Disk Copy operation on the cluster share disk, create a snapshot of the disk, and then perform a Virtual Disk Copy of the snapshot virtual disk.

Cluster.reg

\utility

Cluster

Cluster.reg

Cluster

file located

directory of the Dell

Stand

mode.

file located in the

directory of the

Stand

mode.

Troubleshooting 67

Table A-1. General Cluster Troubleshooting (continued)

Problem Probable Cause Corrective Action

You are using a PowerVault MD3000 or PowerVault MD3000i storage array and one of the following occurs:

• Unable to assign the drive letter to the snapshot virtual disk.

• Unable to access the snapshot virtual disk.

• System Error Log displays a warning with event 59 from

partmgr

that the snapshot virtual disk is a redundant path of a cluster disk.

You are using a PowerVault MD3000 or PowerVault MD3000i storage array in a non-redundant configuration. The Recovery Guru in the

Modular Disk Storage Manager Client

reports that the virtual disks are not on the preferred controller, and the enclosure status LED is blinking amber.

stating

The snapshot virtual disk has been erroneously mapped to the node that does not own the source disk.

The NVSRAM for the non-redundant configuration has not been loaded.

Unmap the snapshot virtual disk from the node not owning the source disk, then assign it to the node that owns the source disk. For more information, see "Using Advanced (Premium) PowerVault Modular Disk Storage Manager Features" section of the Dell Failover Cluster Hardware Installation and Troubleshooting Guide for the specific storage array on the Dell Support website at

support.dell.com/manuals.

For PowerVault MD3000 storage array, load the correct NVSRAM for the non-redundant configuration.

68 Troubleshooting

Index

active/active

about, 45

chkdsk/f

running, 57

cluster

cluster objects, 39 forming a new cluster, 41 joining an existing cluster, 41

Cluster Administrator

about, 37

cluster configurations

active/active, 45 active/passive, 45 supported configurations, 59

cluster nodes

about, 40 states and definitions, 40

cluster objects

about, 39

cluster resources

resource failure, 44 setting resource properties, 41

domain model

selecting, 19

drivers

installing and configuring

Emulex, 27

Emulex HBAs

installing and configuring, 27 installing and configuring

drivers, 27

failback

about, 53

failover

modifying failover policy, 53 policies, 46

failover configurations

for Windows Server 2003,

Enterprise Edition, 46

cluster storage

requirements, 12

Index 69

failover policies, 46

failover pair, 49 failover ring, 52 for Windows Server 2003,

Enterprise Edition, 46 multiway failover, 50 N+I failover, 47

Microsoft Cluster Administrator

about, 37

MSCS

installing and configuring, 29

multiway failover, 50

group affinity

about, 49 configuring, 49

HBA drivers

installing and configuring, 27

host bus adapter

configuring the Fibre Channel

HBA, 27

IP address

assigning to cluster resources and

components, 22 example configuration, 23

N+I failover

configuring group affinity, 47

network adapters

using dual-port for the private

network, 26

network failure

preventing, 39

network interfaces, 40

networking

configuring Windows, 21

operating system

installing, 20 upgrading, 60 Windows Server 2003, Enterprise

Edition

installing,17

70 Index

period values

adjusting, 44

private network

configuring IP addresses, 23 creating separate subnets, 25 using dual-port network

adapters, 26

public network

creating separate subnets, 25

quorum resource

running chkdsk, 57

resource

creating, 43

resource dependencies, 42

threshold

adjusting, 44

troubleshooting

connecting to a cluster, 64 shared storage subsystem, 61-62

upgrading

operating system, 60

upgrading to a cluster solution

before you begin, 59 completing the upgrade, 60

warranty, 12

Windows Server 2003,

Enterprise Edition

cluster configurations, 47, 49-50,

subnets

creating, 25

Index 71

72 Index

Dell PowerVault MD3000 with Windows HA Clusters Quick Reference Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Introduction

Preparing Your Systems for Clustering

Installing Your Cluster Management Software

Understanding Your Failover Cluster

Maintaining Your Cluster

Upgrading to a Cluster Configuration

Troubleshooting

Index