Quick Start Guide for Server Clusters

[LEFT]Quick Start Guide for Server Clusters
Applies To: Windows Server 2003 R2
This guide provides system requirements, installation instructions, and other, step-by-step instructions that you can use to deploy server clusters if you are using Microsoft® Windows Server™ 2003, Enterprise Edition, or Windows Server 2003, Datacenter Edition, operating systems.
The server cluster technology in Windows Server 2003, Enterprise Edition, and Windows Server 2003, Datacenter Edition, helps ensure that you have access to important server-based resources. You can use server cluster technology to create several cluster nodes that appear to users as one server. If one of the nodes in the cluster fails, another node begins to provide service. This is a process known as "failover." In this way, server clusters can increase the availability of critical applications and resources.
[B]Copyright[/B]

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[B]Requirements and Guidelines for Configuring Server Clusters[/B]

The section lists requirements and guidelines that will help you set up a server cluster effectively.
[B]Software requirements and guidelines[/B]


[LIST][*] You must have either Windows Server 2003, Enterprise Edition, or Windows Server 2003, Datacenter Edition, installed on all computers in the cluster. We strongly recommend that you also install the latest service pack for Windows Server 2003. If you install a service pack, the same service pack must be installed on all computers in the cluster.[*] All nodes in the cluster must be of the same architecture. You cannot mix x86-based, Itanium-based, and x64-based computers within the same cluster.[*] Your system must be using a name-resolution service, such as Domain Name System (DNS), DNS dynamic update protocol, Windows Internet Name Service (WINS), or Hosts file. Hosts file is supported as a local, static file method of mapping DNS domain names for host computers to their Internet Protocol (IP) addresses. The Hosts file is provided in the systemroot\System32\Drivers\Etc folder.[*] All nodes in the cluster must be in the same domain. As a best practice, all nodes should have the same domain role (either member server or domain controller), and the recommended role is member server. Exceptions that can be made to these domain role guidelines are described later in this document.[*] When you first create a cluster or add nodes to it, you must be logged on to the domain with an account that has administrator rights and permissions on all nodes in that cluster. The account does not need to be a Domain Admin level account, but can be a Domain User account with Local Admin rights on each node.[/LIST]

[B]Hardware requirements and guidelines[/B]


[LIST][*] For Windows Server 2003, Enterprise Edition, and Windows Server 2003, Datacenter Edition, Microsoft supports only complete server cluster systems chosen from the Windows Catalog. To determine whether your system and hardware components are compatible, including your cluster disks, see the Microsoft Windows Catalog at the [URL="http://go.microsoft.com/fwlink/?LinkId=4287"]Microsoft Web site[/URL]. For a geographically dispersed cluster, both the hardware and software configuration must be certified and listed in the Windows Catalog. For more information, see article 309395, "The Microsoft support policy for server clusters, the Hardware Compatibility List, and the Windows Server Catalog," in the [URL="http://go.microsoft.com/fwlink/?LinkId=46608"]Microsoft Knowledge Base[/URL].[*] If you are installing a server cluster on a storage area network (SAN), and you plan to have multiple devices and clusters sharing the SAN with a cluster, your hardware components must be compatible. For more information, see article 304415, "Support for Multiple Clusters Attached to the Same SAN Device," in the [URL="http://go.microsoft.com/fwlink/?linkid=47293"]Microsoft Knowledge Base[/URL].[*] You must have two mass-storage device controllers in each node in the cluster: one for the local disk, one for the cluster storage. You can choose between SCSI, iSCSI, or Fibre Channel for cluster storage on server clusters that are running Windows Server 2003, Enterprise Edition, or Windows Server 2003, Datacenter Edition. You must have two controllers because one controller has the local system disk for the operating system installed, and the other controller has the shared storage installed.[*] You must have two Peripheral Component Interconnect (PCI) network adapters in each node in the cluster.[*] You must have storage cables to attach the cluster storage device to all computers. Refer to the manufacturer's instructions for configuring storage devices.[*] Ensure that all hardware is identical in all cluster nodes. This means that each hardware component must be the same make, model, and firmware version. This makes configuration easier and eliminates compatibility problems.[/LIST]

[B]Network requirements and guidelines[/B]


[LIST][*] Your network must have a unique NetBIOS name.[*] A WINS server must be available on your network.[*] You must use static IP addresses for each network adapter on each node.[/LIST]
[IMG]http://i.technet.microsoft.com/cc739757.Important%28en-us,WS.10%29.gif[/IMG]Important Server clusters do not support the use of IP addresses assigned from Dynamic Host Configuration Protocol (DHCP) servers.



[LIST][*] The nodes in the cluster must be able to access a domain controller. The Cluster service requires that the nodes be able to contact the domain controller to function correctly. The domain controller must be highly available. In addition, it should be on the same local area network (LAN) as the nodes in the cluster. To avoid a single point of failure, the domain must have at least two domain controllers.[*] Each node must have at least two network adapters. One adapter will be used exclusively for internal node-to-node communication (the private network). The other adapter will connect the node to the client public network. It should also connect the cluster nodes to provide support in case the private network fails. (A network that carries both public and private communication is called a mixed network.)[*] If you are using fault-tolerant network cards or teaming network adapters, you must ensure that you are using the most recent firmware and drivers. Check with your network adapter manufacturer to verify compatibility with the cluster technology in Windows Server 2003, Enterprise Edition, and Windows Server 2003, Datacenter Edition.[/LIST]
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note Using teaming network adapters on all cluster networks concurrently is not supported. At least one of the cluster private networks must not be teamed. However, you can use teaming network adapters on other cluster networks, such as public networks.



[B]Storage requirements and guidelines[/B]


[LIST][*] An external disk storage unit must be connected to all nodes in the cluster. This will be used as the cluster storage. You should also use some type of hardware redundant array of independent disks (RAID).[*] All cluster storage disks, including the quorum disk, must be physically attached to a shared bus.[/LIST]
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note This requirement does not apply to Majority Node Set (MNS) clusters when they are used with some type of software replication method.



[LIST][*] Cluster disks must not be on the same controller as the one that is used by the system drive, except when you are using boot from SAN technology. For more information about using boot from SAN technology, see "Boot from SAN in Windows Server 2003 and Windows 2000 Server" at the [URL="http://go.microsoft.com/fwlink/?LinkId=46609"]Microsoft Web site[/URL].[*] You should create multiple logical unit numbers (LUNs) at the hardware level in the RAID configuration instead of using a single logical disk that is then divided into multiple partitions at the operating system level. We recommend a minimum of two logical clustered drives. This enables you to have multiple disk resources and also allows you to perform manual load balancing across the nodes in the cluster.[*] You should set aside a dedicated LUN on your cluster storage for holding important cluster configuration information. This information makes up the cluster quorum resource. The recommended minimum size for the volume is 500 MB. You should not store user data on any volume on the quorum LUN.[*] If you are using SCSI, ensure that each device on the shared bus (both SCSI controllers and hard disks) has a unique SCSI identifier. If the SCSI controllers all have the same default identifier (the default is typically SCSI ID 7), change one controller to a different SCSI ID, such as SCSI ID 6. If more than one disk will be on the shared SCSI bus, each disk must also have a unique SCSI identifier.[*] Software fault tolerance is not natively supported for disks in the cluster storage. For cluster disks, you must use the NTFS file system and configure the disks as basic disks with all partitions formatted as NTFS. They can be either compressed or uncompressed. Cluster disks cannot be configured as dynamic disks. In addition, features of dynamic disks, such as spanned volumes (volume sets), cannot be used without additional non-Microsoft software.[*] All disks on the cluster storage device must be partitioned as master boot record (MBR) disks, not as GUID partition table (GPT) disks.

[IMG]http://i.technet.microsoft.com/cc739757.f0863a46-af3c-4ef2-b8a1-1819614bcc95%28en-us,WS.10%29.gif[/IMG][/LIST]
[B]Deploying SANs with server clusters[/B]

This section lists the requirements for deploying SANs with server clusters.

[LIST][*] Nodes from different clusters must not be able to access the same storage devices. Each cluster used with a SAN must be deployed in a way that isolates it from all other devices. This is because the mechanism the cluster uses to protect access to the disks can have adverse effects if other clusters are in the same zone. Using zoning to separate the cluster traffic from other cluster or non-cluster traffic prevents this type of interference. For more information, see "Zoning vs. LUN masking" later in this guide.[*] All host bus adapters in a single cluster must be the same type and have the same firmware version. Host bus adapters are the interface cards that connect a cluster node to a SAN. This is similar to the way that a network adapter connects a server to a typical Ethernet network. Many storage vendors require that all host bus adapters on the same zone—and, in some cases, the same fabric—share these characteristics.[*] In a cluster, all device drivers for storage and host bus adapters must have the same software version. We strongly recommend that you use a Storport mini-port driver with clustering. Storport (Storport.sys) is a storage port driver that is provided in Windows Server 2003. It is especially suitable for use with high-performance buses, such as Fibre Channel buses, and RAID adapters.[*] Tape devices should never be used in the same zone as cluster disk storage devices. A tape device could misinterpret a bus reset and rewind at inappropriate times, such as when backing up a large amount of data.[*] In a highly available storage fabric, you should deploy server clusters with multiple host bus adapters using multipath I/O software. This provides the highest level of redundancy and availability.

[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note Failover software for host bus adapters can be version sensitive. If you are implementing a multipath solution for your cluster, you should work closely with your hardware vendor to become fully aware of how the adapter interacts with Windows Server 2003.[/LIST]



[B]Creating a Cluster[/B]

It is important to plan the details of your hardware and network before you create a cluster.
If you are using a shared storage device, ensure that when you turn on the computer and start the operating system, only one node has access to the cluster storage. Otherwise, the cluster disks can become corrupted.
In Windows Server 2003, Enterprise Edition, and Windows Server 2003, Datacenter Edition, logical disks that are not on the same shared bus as the boot partition are not automatically mounted and assigned a drive letter. This helps prevent a server in a complex SAN environment from mounting drives that might belong to another server. (This is different from how new disks are mounted in Microsoft Windows® 2000 Server operating systems.) Although the drives are not mounted by default, we still recommend that you follow the procedures provided in the table later in this section to ensure that the cluster disks will not become corrupted.
The table in this section can help you determine which nodes and storage devices should be turned on during each installation step. The steps in the table pertain to a two-node cluster. However, if you are installing a cluster with more than two nodes, the Node 2 column lists the required state of all other nodes.


Step Node 1 Node 2 Storage Notes Set up networks
On
On
Off
Verify that all storage devices on the shared bus are turned off. Turn on all nodes.
Set up cluster disks
On
Off
On
Shut down all nodes. Turn on the cluster storage, and then turn on the first node.
Verify disk configuration
Off
On
On
Turn off the first node, turn on second node. Repeat for nodes three and four if necessary.
Configure the first node
On
Off
On
Turn off all nodes; and then turn on the first node.
Configure the second node
On
On
On
After the first node is successfully configured, turn on the second node. Repeat for nodes three and four as necessary.
Post-installation
On
On
On
All nodes should be turned on.
[B]Preparing to create a cluster[/B]

Complete the following three steps on each cluster node before you install a cluster on the first node.

[LIST][*] Install Windows Server 2003, Enterprise Edition, or Windows Server 2003, Datacenter Edition, on each node of the cluster. We strongly recommend that you also install the latest service pack for Windows Server 2003. If you install a service pack, the same service pack must be installed on all computers in the cluster.[*] Set up networks.[*] Set up cluster disks.[/LIST]
All nodes must be members of the same domain. When you create a cluster or join nodes to a cluster, you specify the domain user account under which the Cluster service runs. This account is called the Cluster service account (CSA).
[B]Installing the Windows Server 2003 operating system[/B]

Install Windows Server 2003, Enterprise Edition, or Windows Server 2003, Datacenter Edition, on each node of the cluster. For information about how to perform this installation, see the documentation you received with the operating system.
Before configuring the Cluster service, you must be logged on locally with a domain account that is a member of the local administrators group.
[IMG]http://i.technet.microsoft.com/cc739757.Important%28en-us,WS.10%29.gif[/IMG]Important If you attempt to join a node to a cluster that has a blank password for the local administrator account, the installation will fail. For security reasons, Windows Server 2003 operating systems prohibit blank administrator passwords.



[B]Setting up networks[/B]

Each cluster node requires at least two network adapters and must be connected by two or more independent networks. At least two LAN networks (or virtual LANs) are required to prevent a single point of failure. A server cluster whose nodes are connected by only one network is not a supported configuration. The adapters, cables, hubs, and switches for each network must fail independently. This usually means that the components of any two networks must be physically independent.
Two networks must be configured to handle either [B]All communications (mixed network) [/B]or [B]Internal cluster communications only (private network)[/B]. The recommended configuration for two adapters is to use one adapter for the private (node-to-node only) communication and the other adapter for mixed communication (node-to-node plus client-to-cluster communication).
You must have two PCI network adapters in each node. They must be certified in the [URL="http://go.microsoft.com/fwlink/?LinkId=4287"]Microsoft Windows Catalog[/URL] and supported by Microsoft Product Support Services. Assign one network adapter on each node a static IP address, and assign the other network adapter a static IP address on a separate network on a different subnet for private network communication.
Because communication between cluster nodes is essential for smooth cluster operations, the networks that you use for cluster communication must be configured optimally and follow all hardware compatibility-list requirements. For additional information about recommended configuration settings, see article 258750, "Recommended private heartbeat configuration on a cluster server," in the [URL="http://go.microsoft.com/fwlink/?LinkId=46549"]Microsoft Knowledge Base[/URL].
You should keep all private networks physically separate from other networks. Specifically, do not use a router, switch, or bridge to join a private cluster network to any other network. Do not include other network infrastructure or application servers on the private network subnet. To separate a private network from other networks, use a cross-over cable in a two-node cluster configuration or a dedicated hub in a cluster configuration of more than two nodes.
[B]Additional network considerations[/B]


[LIST][*] All cluster nodes must be on the same logical subnet.[*] If you are using a virtual LAN (VLAN), the one-way communication latency between any pair of cluster nodes on the VLAN must be less than 500 milliseconds.[*] In Windows Server 2003 operating systems, cluster nodes exchange multicast heartbeats rather than unicast heartbeats. A heartbeat is a message that is sent regularly between cluster network drivers on each node. Heartbeat messages are used to detect communication failure between cluster nodes. Using multicast technology enables better node communication because it allows several unicast messages to be replaced with a single multicast message. Clusters that consist of fewer than three nodes will not send multicast heartbeats. For additional information about using multicast technology, see article 307962, "Multicast Support Enabled for the Cluster Heartbeat," in the [URL="http://go.microsoft.com/fwlink/?LinkId=46558"]Microsoft Knowledge Base[/URL].[/LIST]
Determine an appropriate name for each network connection. For example, you might want to name the private network "Private" and the public network "Public." This will help you uniquely identify a network and correctly assign its role.
The following figure shows the elements of a four-node cluster that uses a private network.
[IMG]http://i.technet.microsoft.com/cc739757.5a9777c4-811d-43c2-8abc-719f2bd83421%28en-us,WS.10%29.gif[/IMG]
[B]Setting the order of the network adapter binding[/B]

One of the recommended steps for setting up networks is to ensure the network adapter binding is set in the correct order. To do this, use the following procedure.
[B] To set the order of the network adapter binding [/B]
[LIST=1][*] To open [B]Network Connections[/B], click [B]Start[/B], click [B]Control Panel[/B], and then double-click [B]Network Connections[/B].[*] On the [B]Advanced[/B] menu, click [B]Advanced Settings[/B].[*] In [B]Connections[/B], click the connection that you want to modify.[*] Set the order of the network adapter binding as follows:
[LIST][*] External public network[*] Internal private network (Heartbeat)[*] [Remote Access Connections][/LIST]
[*] Repeat this procedure for all nodes in the cluster.[/LIST]

[B]Configuring the private network adapter[/B]

As stated earlier, the recommended configuration for two adapters is to use one adapter for private communication, and the other adapter for mixed communication. To configure the private network adapter, use the following procedure.
[B] To configure the private network adapter [/B]
[LIST=1][*] To open [B]Network Connections[/B], click [B]Start[/B], click [B]Control Panel[/B], and then double-click [B]Network Connections[/B].[*] Right-click the connection for the adapter you want to configure, and then click [B]Properties[/B]. [B]Local Area Properties[/B] opens and looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.99ff46cb-8aa4-4896-b332-c7fc3baeb0ae%28en-us,WS.10%29.gif[/IMG][*] On the [B]General[/B] tab, verify that the [B]Internet Protocol (TCP/IP)[/B] check box is selected, and that all other check boxes in the list are clear.[*] If you have network adapters that can transmit at multiple speeds and that allow you to specify the speed and duplex mode, manually configure the Duplex Mode, Link Speed, and Flow Control settings for the adapters to the same values and settings on all nodes. If the network adapters you are using do not support manual settings, contact your adapter manufacturer for specific information about appropriate speed and duplex settings for your network adapters. The amount of information that is traveling across the heartbeat network is small, but latency is critical for communication. Therefore, if you have the same speed and duplex settings, this helps ensure that you have reliable communication. If the adapters are connected to a switch, ensure that the port settings of the switch match those of the adapters. If you do not know the supported speed of your card and connecting devices, or if you run into compatibility problems, you should set all devices on that path to 10 megabytes per second (Mbps) and Half Duplex.
Teaming network adapters on all cluster networks concurrently is not supported because of delays that can occur when heartbeat packets are transmitted and received between cluster nodes. For best results, when you want redundancy for the private interconnect, you should disable teaming and use the available ports to form a second private interconnect. This achieves the same end result and provides the nodes with dual, robust communication paths.
You can use Device Manager to change the network adapter settings. To open Device Manager, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], double-click [B]Computer Management[/B], and then click [B]Device Manager[/B]. Right-click the network adapter you want to change, and then click [B]Properties[/B]. Click [B]Advanced[/B] to manually change the speed and duplex mode for the adapter. The page that opens looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.38907568-e761-4467-977d-09c94f9363c5%28en-us,WS.10%29.gif[/IMG][*] On the [B]General [/B]tab in [B]Network Connections[/B], select [B]Internet Protocol (TCP/IP)[/B], and click [B]Properties[/B].
Internet Protocol (TCP/IP) Properties opens and looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.baeff252-7435-4732-ae0b-e793a20925be%28en-us,WS.10%29.gif[/IMG][*] On the [B]General[/B] tab, verify you have selected a static IP address that is not on the same subnet or network as any other public network adapter. You should put the private network adapter in one of the following private network ranges:
[LIST][*] 10.0.0.0 through 10.255.255.255 (Class A)[*] 172.16.0.0 through 172.31.255.255 (Class B)[*] 192.168.0.0 through 192.168.255.255 (Class C)[/LIST]
[*] On the [B]General [/B]tab, verify that no values are defined in [B]Default Gateway[/B] under [B]Use the following IP address[/B], and no values are defined under [B]Use the Following DNS server addresses[/B]. After you have done so, click [B]Advanced[/B].[*] On the [B]DNS[/B] tab, verify that no values are defined on the page and that the check boxes for [B]Register this connection's addresses in DNS[/B] and [B]Use this connection's DNS suffix in DNS registration[/B] are clear.[*] On the [B]WINS[/B] tab, verify that no values are defined on the page, and then click [B]Disable NetBIOS over TCP/IP.[/B]
[B]Advanced TCP/IP Settings opens and looks similar to the following figure:[/B]
[IMG]http://i.technet.microsoft.com/cc739757.efdb6fd1-8536-4dd3-96a3-390cfc39f830%28en-us,WS.10%29.gif[/IMG][*] After you have verified the information, click [B]OK[/B]. You might receive the message "This connection has an empty primary WINS address. Do you want to continue?" To continue, click [B]Yes[/B].[*] Repeat this procedure for all additional nodes in the cluster. For each private network adapter, use a different static IP address.[/LIST]

[B]Configuring the public network adapter[/B]

If DHCP is used to obtain IP addresses, it might not be possible to access cluster nodes if the DHCP server is inaccessible. For increased availability, static, valid IP addresses are required for all interfaces on a server cluster. If you plan to put multiple network adapters in each logical subnet, keep in mind that the Cluster service will recognize only one network interface per subnet.

[LIST][*] [B]Verifying connectivity and name resolution[/B]. To verify that the private and public networks are communicating properly, "ping" all IP addresses from each node. To "ping" an IP address means that you search for and verify it. You should be able to ping all IP addresses, both locally and on the remote nodes. To verify the name resolution, ping each node from a client using the node's computer name instead of its IP address. It should only return the IP address for the public network. You might also want to try using the PING –a command to perform a reverse name resolution on the IP addresses.[*] [B]Verifying domain membership[/B]. All nodes in the cluster must be members of the same domain, and they must be able to access a domain controller and a DNS server. They can be configured as member servers or domain controllers. You should have at least one domain controller on the same network segment as the cluster. To avoid having a single point of failure, another domain controller should also be available. In this guide, all nodes are configured as member servers, which is the recommended role.

In a two-node server cluster, if one node is a domain controller, the other node must also be a domain controller. In a four-node cluster, it is not necessary to configure all four nodes as domain controllers. However, when following a "best practices" model of having at least one backup domain controller, at least one of the remaining three nodes should also be configured as a domain controller. A cluster node must be promoted to a domain controller before the Cluster service is configured.

The dependence in Windows Server 2003 on DNS requires that every node that is a domain controller must also be a DNS server if another DNS server that supports dynamic updates is not available.

You should consider the following issues if you are planning to deploy cluster nodes as domain controllers:
[LIST][*] If one cluster node in a two-node cluster is a domain controller, the other node must also be a domain controller.[*] There are performance implications associated with the overhead of running a computer as a domain controller. There is increased memory usage and additional network traffic from replication because these domain controllers must replicate with other domain controllers in the domain and across domains.[*] If the cluster nodes are the only domain controllers, they each must be DNS servers as well. They should point to themselves for primary DNS resolution and to each other for secondary DNS resolution.[*] The first domain controller in the forest or domain will assume all Operations Master Roles. You can redistribute these roles to any node. However, if a node fails, the Operations Master Roles assumed by that node will be unavailable. Because of this, you should not run Operations Master Roles on any cluster node. This includes Schema Master, Domain Naming Master, Relative ID Master, PDC Emulator, and Infrastructure Master. These functions cannot be clustered for high availability with failover.[*] Because of resource constraints, it might not be optimal to cluster other applications such as Microsoft SQL Server™ in a scenario where the nodes are also domain controllers. This configuration should be thoroughly tested in a lab environment before deployment.[/LIST]
Because of the complexity and overhead involved when cluster nodes are domain controllers, all nodes should be member servers.[*] [B]Setting up a Cluster service user account[/B]. The Cluster service requires a domain user account that is a member of the Local Administrators group on each node. This is the account under which the Cluster service can run. Because Setup requires a user name and password, you must create this user account before you configure the Cluster service. This user account should be dedicated to running only the Cluster service and should not belong to an individual.

[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note It is not necessary for the Cluster service account (CSA) to be a member of the Domain Administrators group. For security reasons, domain administrator rights should not be granted to the Cluster service account.


The Cluster service account requires the following rights to function properly on all nodes in the cluster. The Cluster Configuration Wizard grants the following rights automatically:
[LIST][*] Act as part of the operating system[*] Adjust memory quotas for a process[*] Back up files and directories[*] Restore files and directories[*] Increase scheduling priority[*] Log on as a service[/LIST]
You should ensure that the Local Administrator Group has access to the following user rights:


[LIST][*] Debug programs[*] Impersonate a client after authentication[*] Manage auditing and security log[/LIST]
[/LIST]
You can use the following procedure to set up a Cluster service user account.
[B] To set up a Cluster service user account [/B]
[LIST=1][*] Open Active Directory Users and Computers.[*] In the console tree, right-click the folder to which you want to add a user account.
[B]Where?[/B]
[LIST][*] Active Directory Users and Computers/[I]domain node[/I]/[I]folder[/I][/LIST]
[*] Point to [B]New[/B], and then click [B]User.[/B][*] [B]New Object - User[/B] opens and looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.2af20e30-ace4-43ec-a6cc-dc10487a79a6%28en-us,WS.10%29.gif[/IMG][*] Type a first name and last name (these should make sense but are usually not important for this account)[*] In [B]User logon name[/B], type a name that is easy to remember, such as ClusterService1, click the UPN suffix in the drop-down list, and then click [B]Next[/B].[*] [B]In Password[/B] and [B]Confirm password[/B], type a password that follows your organization's guidelines for passwords, and then select [B]User Cannot Change Password[/B] and [B]Password Never Expires[/B]. Click [B]Finish[/B] to create the account.
If your administrative security policy does not allow the use of passwords that never expire, you must renew the password and update the Cluster service configuration on each node before the passwords expire.[*] In the console tree of the Active Directory Users and Computers snap-in, right-click [B]Cluster[/B], and then click [B]Properties[/B].[*] Click [B]Add Members to a Group[/B].[*] Click [B]Administrators[/B], and then click [B]OK[/B]. This gives the new user account administrative permissions on the computer.[/LIST]


[B]Setting up disks[/B]

This section includes information and step-by-step procedures you can use to set up disks.
[IMG]http://i.technet.microsoft.com/cc739757.Important%28en-us,WS.10%29.gif[/IMG]Important To avoid possible corruption of cluster disks, ensure that both the Windows Server 2003 operating system and the Cluster service are installed, configured, and running on at least one node before you start the operating system on another node in the cluster.


[B]Quorum resource[/B]

The quorum resource maintains the configuration data necessary for recovery of the cluster. The quorum resource is generally accessible to other cluster resources so that any cluster node has access to the most recent database changes. There can only be one quorum disk resource per cluster.
The requirements and guidelines for the quorum disk are as follows:

[LIST][*] The quorum disk should be at least 500 MB in size.[*] You should use a separate LUN as the dedicated quorum resource.[*] A disk failure could cause the entire cluster to fail. Because of this, we strongly recommend that you implement a hardware RAID solution for your quorum disk to help guard against disk failure. Do not use the quorum disk for anything other than cluster management.[/LIST]
When you configure a cluster disk, it is best to manually assign drive letters to the disks on the shared bus. The drive letters should not start with the next available letter. Instead, leave several free drive letters between the local disks and the shared disks. For example, start with drive Q as the quorum disk and then use drives R and S for the shared disks. Another method is to start with drive Z as the quorum disk and then work backward through the alphabet with drives X and Y as data disks. You might also want to consider labeling the drives in case the drive letters are lost. Using labels makes it easier to determine what the drive letter was. For example, a drive label of "DriveR" makes it easy to determine that this drive was drive letter R. We recommend that you follow these best practices when assigning driver letters because of the following issues:

[LIST][*] Adding disks to the local nodes can cause the drive letters of the cluster disks to be revised up by one letter.[*] Adding disks to the local nodes can cause a discontinuous flow in the drive lettering and result in confusion.[*] Mapping a network drive can conflict with the drive letters on the cluster disks.[/LIST]
The letter Q is commonly used as a standard for the quorum disk. Q is used in the next procedure.
The first step in setting up disks for a cluster is to configure the cluster disks you plan to use. To do this, use the following procedure.
[B] To configure cluster disks [/B]
[LIST=1][*] Make sure that only one node in the cluster is turned on.[*] Open Computer Management (Local).[*] In the console tree, click [B]Computer Management (Local)[/B], click [B]Storage[/B], and then click [B]Disk Management[/B].[*] When you first start Disk Management after installing a new disk, a wizard appears that provides a list of the new disks detected by the operating system. If a new disk is detected, the Write Signature and Upgrade Wizard starts. Follow the instructions in the wizard.[*] Because the wizard automatically configures the disk as dynamic storage, you must reconfigure the disk to basic storage. To do this, right-click the disk, and then click [B]Convert To Basic Disk[/B].[*] Right-click an unallocated region of a basic disk, and then click [B]New Partition[/B].[*] In the New Partition Wizard, click [B]Next[/B], click [B]Primary partition[/B], and then click [B]Next[/B].[*] By default, the maximum size for the partition is selected. Using multiple logical drives is better than using multiple partitions on one disk because cluster disks are managed at the LUN level, and logical drives are the smallest unit of failover.[*] Change the default drive letter to one that is deeper into the alphabet. For example, start with drive Q as the quorum disk, and then use drives R and S for the data disks.[*] Format the partition with the NTFS file system.[*] In [B]Volume Label[/B], enter a name for the disk; for example, "Drive Q." Assigning a drive label for cluster disks reduces the time it takes to troubleshoot a disk recovery scenario.
After you have finished entering values for the new partition, it should look similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.dfca241d-a77c-48e2-a17f-57e1f31f2e17%28en-us,WS.10%29.gif[/IMG] [IMG]http://i.technet.microsoft.com/cc739757.Important%28en-us,WS.10%29.gif[/IMG]Important Ensure that all disks are formatted as MBR; GPT disks are not supported as cluster disks.[/LIST]
After you have configured the cluster disks, you should verify that the disks are accessible. To do this, use the following procedure.
[B] To verify that the cluster disks are accessible [/B]
[LIST=1][*] Open Windows Explorer.[*] Right-click one of the cluster disks, such as "Drive Q," click [B]New[/B], and then click [B]Text Document[/B].[*] Verify that the text document was created and written to the specified disk, and then delete the document from the cluster disk.[*] Repeat steps 1 through 3 for all cluster disks to verify that they are all accessible from the first node.[*] Turn off the first node, and then turn on the second node.[*] Repeat steps 1 through 3 to verify that the disks are all accessible from the second node.[*] Repeat again for any additional nodes in the cluster.[*] When finished, turn off the nodes and then turn on the first node again.[/LIST]



[B]Creating a new server cluster[/B]

In the first phase of creating a new server cluster, you must provide all initial cluster configuration information. To do this, use the New Server Cluster Wizard.
[IMG]http://i.technet.microsoft.com/cc739757.Important%28en-us,WS.10%29.gif[/IMG]Important Before configuring the first node of the cluster, make sure that all other nodes are turned off. Also make sure that all cluster storage devices are turned on.


The following procedure explains how to use the New Server Cluster Wizard to configure the first cluster node.
[B] To configure the first node [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] In the [B]Open Connection to Cluster dialog box[/B], in [B]Action[/B], select [B]Create new cluster, and then click OK[/B].[*] The New Server Cluster Wizard appears. Verify that you have the necessary information to continue with the configuration, and then click [B]Next[/B] to continue.
[IMG]http://i.technet.microsoft.com/cc739757.4102eeac-81c0-4572-a3af-350d33a79ae3%28en-us,WS.10%29.gif[/IMG][*] In [B]Domain[/B], select the name of the domain in which the cluster will be created. In [B]Cluster name[/B], enter a unique NetBIOS name. It is best to follow the DNS namespace rules when entering the cluster name. For more information, see article 254680, "DNS Namespace Planning," in the [URL="http://support.microsoft.com/?id=254680"]Microsoft Knowledge Base[/URL].
[IMG]http://i.technet.microsoft.com/cc739757.71c8206e-6c9b-4afa-a076-0cb58bb998e3%28en-us,WS.10%29.gif[/IMG][*] On the [B]Domain Access Denied[/B] page, if you are logged on locally with an account that is not a domain account with local administrative permissions, the wizard will prompt you to specify an account. This is not the account the Cluster service will use to start the cluster.
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note If you have the appropriate credentials, the [B]Domain Access Denied[/B] screen will not appear.


[IMG]http://i.technet.microsoft.com/cc739757.26de508f-ec1e-49b5-8fa0-95fdc62715af%28en-us,WS.10%29.gif[/IMG][*] Since it is possible to configure clusters remotely, you must verify or type the name of the computer you are using as the first node. On the [B]Select Computer[/B] page, verify or type the name of the computer you plan to use.
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note The wizard verifies that all nodes can see the cluster disks. In some complicated SANs, the target IDs for the disks might not match on all the cluster nodes. If this occurs, the Setup program might incorrectly determine that the disk configuration is not valid. To address this issue, click [B]Advanced[/B], and then click [B]Advanced (minimum) configuration[/B].


[IMG]http://i.technet.microsoft.com/cc739757.87afc1ef-182c-44a5-936b-2f6cda7e977e%28en-us,WS.10%29.gif[/IMG][*] On the [B]Analyzing Configuration[/B] page, Setup analyzes the node for possible hardware or software issues that can cause installation problems. Review any warnings or error messages that appear. Click [B]Details[/B] to obtain more information about each warning or error message.
[IMG]http://i.technet.microsoft.com/cc739757.8a7dced1-71d3-4a7c-ba20-af15cd7f079e%28en-us,WS.10%29.gif[/IMG][*] On the [B]IP Address[/B] page, type the unique, valid, cluster IP address, and then click [B]Next[/B]. The wizard automatically associates the cluster IP address with one of the public networks by using the subnet mask to select the correct network. The cluster IP address should be used for administrative purposes only, and not for client connections.
[IMG]http://i.technet.microsoft.com/cc739757.93134f8e-72cf-4a20-a872-cf90988a9b00%28en-us,WS.10%29.gif[/IMG][*] On the [B]Cluster Service Account[/B] page, type the user name and password of the Cluster service account that was created during pre-installation. In [B]Domain[/B], select the domain name, and then click [B]Next[/B]. The wizard verifies the user account and password.
[IMG]http://i.technet.microsoft.com/cc739757.0a50e318-3c37-46fb-9bad-2ec824e46200%28en-us,WS.10%29.gif[/IMG][*] On the [B]Proposed Cluster Configuration[/B] page, review the information for accuracy. You can use the summary information to reconfigure the cluster if a system recovery occurs. You should keep a hard copy of this summary information with the change management log at the server. To continue, click [B]Next[/B].
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note If you want, you can click [B]Quorum[/B] to change the quorum disk designation from the default disk resource. To make this change, in the [B]Quorum resource[/B] box, click a different disk resource. If the disk has more than one partition, click the partition where you want the cluster-specific data to be kept, and then click [B]OK[/B].


[IMG]http://i.technet.microsoft.com/cc739757.79824d6c-5f67-4bac-9507-e30d0a785dc6%28en-us,WS.10%29.gif[/IMG][*] On the [B]Creating the Cluster[/B] page, review any warnings or error messages that appear while the cluster is being created. Click to expand each warning or error message for more information. To continue, click [B]Next[/B].
[IMG]http://i.technet.microsoft.com/cc739757.f4afac71-9dc4-427c-8654-194a75a6672a%28en-us,WS.10%29.gif[/IMG][*] Click [B]Finish[/B] to complete the cluster configuration.
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note To view a detailed summary, click [B]View Log[/B], or view the text file stored at the following location:


%SystemRoot%\System32\LogFiles\Cluster\ClCfgSrv.Log
[IMG]http://i.technet.microsoft.com/cc739757.d828dcd6-f989-4ba0-a9f9-364998f7f566%28en-us,WS.10%29.gif[/IMG][/LIST]

[B]Validating the cluster installation[/B]

You should validate the cluster configuration of the first node before configuring the second node. To do this, use the following procedure.
[B] To validate the cluster configuration [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] Verify that all cluster resources are successfully up and running. Under [B]State[/B], all resources should be "Online."[/LIST]

[B]Configuring subsequent nodes[/B]

After you install the Cluster service on the first node, it takes less time to install it on subsequent nodes. This is because the Setup program uses the network configuration settings configured on the first node as a basis for configuring the network settings on subsequent nodes. You can also install the Cluster service on multiple nodes at the same time and choose to install it from a remote location.
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note The first node and all cluster disks must be turned on. You can then turn on all other nodes. At this stage, the Cluster service controls access to the cluster disks, which helps prevent disk corruption. You should also verify that all cluster disks have had resources automatically created for them. If they have not, manually create them before adding any more nodes to the cluster.


After you have configured the first node, you can use the following procedure to configure subsequent nodes.
[B] To configure the second node [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] In the [B]Open Connection to Cluster[/B] dialog box, in [B]Action[/B], select [B]Add nodes to cluster[/B]. Then, in [B]Cluster or server name[/B], type the name of an existing cluster, select a name from the drop-down list box, or click [B]Browse[/B] to search for an available cluster, and then click [B]OK[/B] to continue.[*] When the Add Nodes Wizard appears, click[B] Next[/B] to continue.[*] If you are not logged on with the required credentials, you will be asked to specify a domain account that has administrator rights and permissions on all nodes in the cluster.[*] In the [B]Domain[/B] list, click the domain where the server cluster is located, make sure that the server cluster name appears in the [B]Cluster name[/B] box, and then click [B]Next[/B].[*] In the [B]Computer name[/B] box, type the name of the node that you want to add to the cluster. For example, to add Node2, you would type Node2.
[IMG]http://i.technet.microsoft.com/cc739757.5b986e07-dd14-452c-8dab-b7475fcef338%28en-us,WS.10%29.gif[/IMG][*] Click [B]Add[/B], and then click [B]Next[/B].[*] When the Add Nodes Wizard has analyzed the cluster configuration successfully, click [B]Next[/B].[*] On the [B]Cluster Service Account[/B] page, in [B]Password[/B], type the password for the Cluster service account. Ensure that the correct domain for this account appears in the [B]Domain[/B] list, and then click [B]Next[/B].[*] On the [B]Proposed Cluster Configuration[/B] page, view the configuration details to verify that the server cluster IP address, the networking information, and the managed disk information are correct, and then click [B]Next[/B].[*] When the cluster is configured successfully, click [B]Next[/B], and then click [B]Finish[/B].[/LIST]

[B]Configuring the server cluster after installation[/B]

[B]Heartbeat configuration[/B]

After the network and the Cluster service have been configured on each node, you should determine the network's function within the cluster. Using Cluster Administrator, select the [B]Enable this network for cluster use[/B] check box and select from among the following options.


Option Description Client access only (public network)
Select this option if you want the Cluster service to use this network adapter only for external communication with other clients. No node-to-node communication will take place on this network adapter.
Internal cluster communications only (private network)
Select this option if you want the Cluster service to use this network only for node-to-node communication.
All communications (mixed network)
Select this option if you want the Cluster service to use the network adapter for node-to-node communication and for communication with external clients. This option is selected by default for all networks.
This guide assumes that only two networks are in use. It explains how to configure these networks as one mixed network and one private network. This is the most common configuration.
Use the following procedure to configure the heartbeat.
[B] To configure the heartbeat [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] In the console tree, double-click [B]Cluster Configuration[/B], and then click [B]Networks[/B].[*] In the details pane, right-click the private network you want to enable, and then click [B]Properties[/B]. [B]Private Properties[/B] opens and looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.87c2ccf3-3e89-4e12-b354-adb27c0f4167%28en-us,WS.10%29.gif[/IMG][*] Select the [B]Enable this network for cluster use[/B] check box.[*] Click [B]Internal cluster communications only (private network)[/B], and then click [B]OK[/B].[*] In the details pane, right-click the public network you want to enable, and then click [B]Properties[/B].[B] Public Properties[/B] opens and looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.8fa031bf-4762-4343-9f74-2f1df9254186%28en-us,WS.10%29.gif[/IMG][*] Select the [B]Enable this network for cluster use[/B] check box.[*] Click [B]All communications (mixed network)[/B], and then click [B]OK[/B].[/LIST]
[B]Prioritize the order of the heartbeat adapter[/B]

After you have decided the roles in which the Cluster service will use the network adapters, you must prioritize the order in which the adapters will be used for internal cluster communication. To do this, use the following procedure.
[B] To configure network priority [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] In the console tree, click the cluster you want.[*] On the [B]File[/B] menu, click [B]Properties[/B].
[IMG]http://i.technet.microsoft.com/cc739757.83183c15-0920-4cfd-a0b7-1bc5d7e59e05%28en-us,WS.10%29.gif[/IMG][*] Click the [B]Network Priority[/B] tab.[*] In [B]Networks used for internal cluster communications[/B], click a network.[*] To increase the network priority, click [B]Move Up[/B]; to lower the network priority click [B]Move Down.[/B][*] When you are finished, click [B]OK.[/B]
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note If multiple networks are configured as private or mixed, you can specify which one to use for internal node communication. It is usually best for private networks to have higher priority than mixed networks.[/LIST]


[B]Quorum disk configuration[/B]

The New Server Cluster Wizard and the Add Nodes Wizard automatically select the drive used for the quorum device. The wizard automatically uses the smallest partition it finds that is larger then 50 MB. If you want to, you can change the automatically selected drive to a dedicated one that you have designated for use as the quorum. The following procedure explains what to do if you want to use a different disk for the quorum resource.
[B] To use a different disk for the quorum resource [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] If one does not already exist, create a physical disk or other storage-class resource for the new disk.[*] In the console tree, click the cluster name.[*] On the [B]File[/B] menu, click [B]Properties, and then click the Quorum tab[/B]. The quorum property page opens and looks similar to the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.5bb8c5a7-d296-4a83-9d48-f70eb1532e5b%28en-us,WS.10%29.gif[/IMG][*] On the [B]Quorum [/B]tab, click [B]Quorum resource[/B], and then select the new disk or storage-class resource that you want to use as the quorum resource for the cluster.[*] In [B]Partition[/B], if the disk has more than one partition, click the partition where you want the cluster specific data kept.[*] In [B]Root path[/B], type the path to the folder on the partition; for example:
[B]\MSCS[/B][/LIST]



[B]Testing the Server Cluster[/B]

After Setup, there are several methods you can use to verify a cluster installation.

[LIST][*] [B]Use Cluster Administrator[/B]. After Setup is run on the first node, open Cluster Administrator, and then try to connect to the cluster. If Setup was run on a second node, start Cluster Administrator on either the first or second node, attempt to connect to the cluster, and then verify that the second node is listed.[*] [B]Services snap-in[/B]. Use the Services snap-in to verify that the Cluster service is listed and started.[*] [B]Event log[/B]. Use Event Viewer to check for [B]ClusSvc[/B] entries in the system log. You should see entries that confirm the Cluster service successfully formed or joined a cluster.[/LIST]
[B]Testing whether group resources can fail over[/B]

You might want to ensure that a new group is functioning correctly. To do this, use the following procedure.
[B] To test whether group resources can fail over [/B]
[LIST=1][*] Open Cluster Administrator. To do this, click [B]Start[/B], click [B]Control Panel[/B], double-click [B]Administrative Tools[/B], and then double-click [B]Cluster Administrator[/B].[*] In the console tree, double-click the [B]Groups[/B] folder.[*] In the console tree, click a group.[*] On the [B]File[/B] menu, click [B]Move Group[/B]. On a multi-node cluster server, when using [B]Move Group[/B], select the node to move the group to. Make sure the [B]Owner[/B] column in the details pane reflects a change of owner for all of the group's dependencies.[*] If the group resources successfully fail over, the group will be brought online on the second node after a short period of time.[/LIST]


[B]SCSI Drive Installations[/B]

This section of the guide provides a generic set of instructions for parallel SCSI drive installations.
[IMG]http://i.technet.microsoft.com/cc739757.Important%28en-us,WS.10%29.gif[/IMG]Important If the SCSI hard disk vendor’s instructions differ from the instructions provided here, follow the instructions supplied by the vendor.


The SCSI bus listed in the hardware requirements must be configured before you install the Cluster service. This configuration applies to the following:

[LIST][*] The SCSI devices.[*] The SCSI controllers and the hard disks. This is to ensure that they work properly on a shared SCSI bus.[*] The termination of the shared bus. If a shared bus must be terminated, it must be done properly. The shared SCSI bus must have a terminator at each end of the bus. It is possible to have multiple shared SCSI buses between the nodes of a cluster.[/LIST]
In addition to the following information, refer to documentation from the manufacturer of your SCSI device.
[B]Configuring SCSI devices[/B]

Each device on the shared SCSI bus must have a unique SCSI identification number. Because most SCSI controllers default to SCSI ID 7, configuring the shared SCSI bus includes changing the SCSI ID number on one controller to a different number, such as SCSI ID 6. If there is more than one disk that will be on the shared SCSI bus, each disk must have a unique SCSI ID number.


[B]Storage Area Network Considerations[/B]

Fibre Channel systems are required for all server clusters running 64-bit versions of Windows Server 2003, Enterprise Edition, or Windows Server 2003, Datacenter Edition. It is also best to use Fibre Channel systems for clusters of three or more nodes. Two methods of Fibre Channel-based storage are supported in a cluster that is running Windows Server 2003: arbitrated loops and switched fabric.
[IMG]http://i.technet.microsoft.com/cc739757.note%28en-us,WS.10%29.gif[/IMG]Note To determine which type of Fibre Channel hardware to use, read the Fibre Channel vendor's documentation.


[B]Fibre Channel arbitrated loops (FC-AL)[/B]

A Fibre Channel arbitrated loop (FC-AL) is a set of nodes and devices connected into a single loop. FC-AL provides a cost-effective way to connect up to 126 devices into a single network.
Fibre Channel arbitrated loops provide a solution for a small number of devices in a relatively fixed configuration. All devices on the loop share the media, and any packet traveling from one device to another must pass through all intermediate devices. FC-AL is a good choice if a low number of cluster nodes is sufficient to meet your high-availability requirements.
FC-AL offers the following advantages:

[LIST][*] The cost is relatively low.[*] Loops can be expanded to add storage; however, nodes cannot be added.[*] Loops are easy for Fibre Channel vendors to develop.[/LIST]
The disadvantage of FC-ALs is that they can be difficult to deploy successfully. This is because every device on the loop shares the media, which causes the overall bandwidth of the cluster to be lower. Some organizations might also not want to be restricted by the 126-device limit. Having more than one cluster on the same arbitrated loop is not supported.

[B]Fiber Channel switched fabric (FC-SW)[/B]

With Fibre Channel switched fabric, switching hardware can link multiple nodes together into a matrix of Fibre Channel nodes. A switched fabric is responsible for device interconnection and switching. When a node is connected to a Fibre Channel switching fabric, it is responsible for managing only the single point-to-point connection between itself and the fabric. The fabric handles physical interconnections to other nodes, transporting messages, flow control, and error detection and correction. Switched fabrics also offer very fast switching latency.
The switching fabric can be configured to allow multiple paths between the same two ports. It provides efficient sharing (at the cost of higher contention) of the available bandwidth. It also makes effective use of the burst nature of communications with high-speed peripheral devices.
[IMG]http://i.technet.microsoft.com/cc739757.36cdcb9b-cf53-4b32-97a9-7119f29f5061%28en-us,WS.10%29.gif[/IMG] Other advantages to using switched fabric include the following:

[LIST][*] It is easy to deploy.[*] It can support millions of devices.[*] The switches provide fault isolation and rerouting.[*] There is no shared media, which allows faster communication in the cluster.[/LIST]

[B]Zoning vs. LUN masking[/B]

Zoning and LUN masking are important to SAN deployments, especially if you are deploying a SAN with a server cluster that is running Windows Server 2003.
[B]Zoning[/B]

Many devices and nodes can be attached to a SAN. With data stored in a single storage entity (known as a "cloud") it is important to control which hosts have access to specific devices. Zoning allows administrators to partition devices in logical volumes, thereby reserving the devices in a volume for a server cluster. This means that all interactions between cluster nodes and devices in the logical storage volumes are isolated within the boundaries of the zone; other non-cluster members of the SAN are not affected by cluster activity. The elements used in zoning are shown in the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.379bbfc4-b644-42ed-bce8-92eb4cf5f5d7%28en-us,WS.10%29.gif[/IMG] You must implement zoning at the hardware level with the controller or switch, not through software. This is because zoning is a security mechanism for a SAN-based cluster. Unauthorized servers cannot access devices inside the zone. Access control is implemented by the switches in the fabric, so a host adapter cannot gain access to a device for which it has not been configured. With software zoning, the cluster would not be secure if the software component failed.
In addition to providing cluster security, zoning also limits the traffic flow within a given SAN environment. Traffic between ports is routed only to segments of the fabric that are in the same zone.

[B]LUN masking[/B]

A logical unit number (LUN) is a logical disk defined within a SAN. Server clusters see LUNs and act as though the LUNs are physical disks. With LUN masking, which is performed at the controller level, you can define relationships between LUNs and cluster nodes. Storage controllers usually provide the means for creating LUN-level access controls that allow one or more hosts to access a given LUN. With access control at the storage controller, the controller itself can enforce access policies to the devices.
LUN masking provides security at a more detailed level than zoning. This is because LUNs allow for zoning at the port level. For example, many SAN switches allow overlapping zones, which enable a storage controller to reside in multiple zones. Multiple clusters in multiple zones can share the data on those controllers. The elements used in LUN masking are shown in the following figure:
[IMG]http://i.technet.microsoft.com/cc739757.28be5dcb-a3c1-451b-aa85-779ada2558ea%28en-us,WS.10%29.gif[/IMG]


[B]Other Resources[/B]

For a comprehensive list of hardware and software supported by Windows operating systems, see one of the following:

[LIST][*] Windows Catalog at the [URL="http://go.microsoft.com/fwlink/?LinkId=48250"]Microsoft Web site[/URL].[*] Hardware and software compatibility information in the Windows Server Catalog at the [URL="http://go.microsoft.com/fwlink/?LinkId=4287"]Microsoft Web site[/URL][/LIST]
[/LEFT]