An Oracle White Paper June Deploying a Microsoft SQL Server 2008 Database on the Sun ZFS Storage Appliance

Transcription

1 An Oracle White Paper June 2011 Deploying a Microsoft SQL Server 2008 Database on the Sun ZFS Storage Appliance

2 Introduction... 1 Methodology Used for Example Deployment... 2 Microsoft Windows 2008 Server... 2 Sun ZFS Storage Appliance... 2 Administering the Sun ZFS Storage Appliance... 2 Creating a Storage Resource (Project)... 2 Modifying a File System... 4 Using a CIFS Share for a Microsoft SQL Server Database... 5 Creating a File System on a CIFS Share... 5 Enabling Authentication and Setting Access Permissions... 8 Troubleshooting SMB (CIFS) Services Creating a Database on a CIFS Share Using a Block Protocol Volume for a Microsoft SQL Server Database Configuring iscsi Protocol Access to a LUN on the Sun ZFS Storage Appliance Configuring Fibre Channel Protocol Access to a LUN on the Sun ZFS Storage Appliance Creating a New Block Protocol LUN Configuring the Windows Server to Connect to an External iscsi Volume Creating a File System on a Block Target Precaution When Resizing a Volume Creating a Database on an Block-Protocol Target Creating a Database on the Block Protocol Volume Increasing the Size of the Block Protocol LUN Testing Performance of a SQL Server 2008 Deployment Conclusion For More Information... 44

3 Introduction Microsoft SQL Server 2008 is relational database management system software that has found wide adoption in the industry, covering a broad range of applications from online transactional processing (OLTP) applications, such as Enterprise Resource Planning (ERP) systems, to online analytical processing (OLAP) data warehouses. It can be tightly integrated with Microsoft Active Directory service. Microsoft SQL Server databases use a flexible filebased storage model to store table records, indexes, and logs. This paper describes using Sun Unified Storage from Oracle and a Microsoft Windows 2008 Server with Microsoft SQL Server 2008 to enable the SQL Server to run a database on a file system that is based on a Common Internet File System (CIFS) share or an iscsi target volume. The Sun ZFS Storage Appliance provides shared storage resources that are published using CIFS or iscsi protocol. These CIFS shares or iscsi targets can be used for SQL Server database files. Note: An iscsi target volume is interpreted as a regular hard disk by the Microsoft Windows operating system and is usually addressed by Microsoft SQL Server using a drive letter. However, a shared folder on a remote system must be addressed using its Microsoft universal naming convention (UNC) path when Microsoft SQL Server uses the storage resource for storing datafiles and logs for its databases. When a CIFS share on a remote system specified by a UNC path is used, a create database statement will fail unless the Microsoft SQL Server trace flag 1807 is set. Additional precautions and recommendations for the use of network-attached storage for Microsoft SQL Server databases are given in the Microsoft Knowledge Base article ( This paper is intended for readers who have experience with the administration of Microsoft Windows Server 2008 R2 and Microsoft SQL Server The Sun ZFS Storage Appliance product family includes the Sun ZFS Storage 7120, 7320, 7420, and 7720 appliances. The procedures in this paper apply to all models. 1

4 Methodology Used for Example Deployment This section describes the hardware and software components that were used for the example described in this paper. Microsoft Windows 2008 Server The Microsoft Windows 2008 server is running on a Sun Fire X4450 server with: 4 quad-core Intel Xeon L7345, 1.87 GHz processors 12 GB RAM The software running on the server includes: Microsoft Windows Server 2008 Release 2 Enterprise x64 Edition Microsoft SQL Server 2008 (64-bit) The operating system and Microsoft SQL Server 2008 binaries, as well as the databases internal to Microsoft SQL Server (master, msdb, tempdb), reside on partitions on Sun Fire X4450 server internal disks, while the user database resides on network-attached storage. Sun ZFS Storage Appliance The Sun ZFS Storage 7120 example configuration includes: 2 TB storage capacity 24 GB RAM The configuration is running the Sun ZFS Storage Appliance Version 2010.Q3 software. One ZFS storage pool with a capacity of 3 TB has been created from 12 mirrored disks. Administering the Sun ZFS Storage Appliance This section describes the features of the Sun ZFS Storage Appliance that are generally used when the Sun ZFS Storage Appliance is configured and managed using the web-based graphical user interface (GUI) accessible at the URL address of Sun Storage 7000>:215. Creating a Storage Resource (Project) On a Sun ZFS Storage Appliance, a files system is created as part of a project. The project is at the top level of a hierarchy of storage objects that depend on each other, under which are located file systems and then snapshots and then clones (Project > File System > Snapshot > Clone). At the project level, settings are defined on three configuration tabs: General, Protocol, and Access. Settings on these tabs can be inherited by its subordinate objects. For the configuration used for this 2

5 paper, separate projects were created for volumes to be published using CIFS protocol and volumes to be published using iscsi protocol. Specifying General Settings Values for a number of configuration settings are specified on the General tab for a project including: Quota and Reservation settings for space usage for data The default mount point for project file systems Default permissions for User, Group, and Other Default parameters for the creation of logical unit numbers (LUNs) Figure 1 shows the settings for the CIFS share project. The same values for General settings are used for the iscsi share project except for the file system user permissions under Default Settings. For the iscis share project, default values for user permissions are retained as shown below: User: nobody Group: root Permissions: User RWX Group --- Other --- Figure 1. General settings specified for the CIFS share project 3

6 Specifying Protocol Settings The default values are used for the protocol settings for both the CIFS share and iscsi share projects. Settings for protocols are specified on the Protocols tab for the CIFS share project as shown in Figure 2. Figure 2. Protocol default settings used for the CIFS share project Specifying Access Settings Access settings are specified on the Access tab for the project. The default settings were kept at their default values for both projects as shown in Figure 3. Figure 3. Access default settings used for the CIFS share project Modifying a File System To edit the configuration of a storage object, such as a file system or snapshot, or to delete an object, moved the cursor over the object to display a set of icons, which appear to the left or right of the object. In Figure 4, an entry for a file system has been highlighted to reveal edit (pencil) and destroy (trash can) icons to the right of the entry. Select the pencil icon to modify the configuration settings for the file system Figure 4. Displaying the editing icons associated with an object 4

7 Using a CIFS Share for a Microsoft SQL Server Database The CIFS protocol requires that users who map a CIFS share or who access data on such a share are authenticated either against local account information or by passing the credentials to a central user management instance, such as LDAP or Active Directory. To enable the Sun ZFS Storage Appliance to authenticate a Windows user who is creating and modifying files on a CIFS share, two requirements must be met: The service account for the MSSQLSERVER service must be defined in Active Directory as described in the Microsoft SQL Server product documentation. The Sun ZFS Storage Appliance must be able to access the user information in Active Directory to verify the credentials of the Microsoft SQL Server service account. Therefore, the Sun ZFS Storage Appliance must be a member in the Active Directory domain. Joining the Sun ZFS Storage Appliance to the Active Domain is described in the section Enabling Authentication and Setting Access Permissions. The following sections describe how to set up a CIFS share on a Sun ZFS Storage Appliance attached to a Windows Server to be used as a storage resource to host Microsoft SQL Server data files. Creating a File System on a CIFS Share To create a new file system in a project, complete these steps in the Sun ZFS Storage Appliance GUI: 1. Go to Shares > Projects and select the project to which the file system is to be added. A window listing the file systems in the project is displayed. Figure 5 shows no file systems have yet been defined for the CIFS share project called MS_SQLSERVER. Figure 5. Creating a new file system in the CIFS share project MS_SQLSERVER 5

8 2. To add a file system to the project, click on the + icon next to Filesystems. The screen shown in Figure 6 is displayed. Figure 6. Defining parameters for a new file system in the CIFS share project 3. Provide values for the file system parameters as appropriate and click Apply. The new file system MSSQL, created for the example, appears in the Filesystem list for the project as shown in Figure To set the properties for the new file system, place the cursor over the entry for the file system to display its editing icons at the right (as shown in Figure 7) and then click on the pencil icon. Figure 7. New file system listed for the CIFS share project 5. Select the Protocols tab to display the Protocols window shown in Figure In the SMB section, specify the Resource Name under which the CIFS share is to be published. For this example, the resource name is MSSQL_Data. Assigning a resource name makes the file system accessible using CIFS. 6

9 Figure 8. Configuring the SMB protocol for the MSSQL file system in the CIFS share project 7

10 Enabling Authentication and Setting Access Permissions SQL Server requires a user to be created to run the database as a Windows Service. The user resides in Active Directory, as is normal in a typical Windows environment. This user has complete control of the share and can perform any file system operation. Therefore, the Sun ZFS Storage Appliance must be in Active Directory to enable the authentication of the credentials of the SQL Server user account. To join the Sun ZFS Storage Appliance to the Active Directory domain, complete these steps in the Sun ZFS Storage Appliance GUI: 1. Go to Configuration > Services > Active Directory to display the Active Directory window shown in Figure 9. Figure 9. Selecting option to join the Sun ZFS Storage Appliance to the Active Directory domain 2. Click Join Domain to open the window shown in Figure To add the Sun ZFS Storage Appliance to Active Directory, enter the required information and click Apply. Note: If you encounter authentication issues when attempting to join the Sun ZFS Storage Appliance to the Active Directory domain, see the section Troubleshooting SMB (CIFS) Services below. Figure 10. Joining the Sun ZFS Storage Appliance to the Active Directory domain 8

11 4. Assign permissions at the file level for the Active Directory user account by completing these steps: a. Go to Shares > Projects. Select the project containing the file system for which access permissions are to be specified. b. Place the cursor over the entry for the file system to be modified. Click the pencil icon that appears to the right of the entry to edit the file system parameters. c. Click the Access tab to display the window shown in Figure 11. d. Under Root Directory ACL, change Owner to Named User and enter the name of the target Microsoft SQL Server service account. See Figure 11. Figure 11. Setting access permissions for a file system in a CIFS share project e. Open the Edit ACL Entry window shown in Figure 12 to set permissions by moving the cursor over the Root Directory ACL entry to be edited and clicking the pencil symbol that appears to the right of the entry. Figure 12. Assigning permissions for the CIFS share project 9

12 Troubleshooting SMB (CIFS) Services If an error message is displayed that states that access is denied or that the operating system cannot log on the user, and you have entered the correct user name and password, you may need to change the LAN Manager Compatibility Level setting. The authentication modes supported on the Sun ZFS Storage appliance are LAN Manager (LM), NT LAN Manager (NTLM), LMv2, and NTLMv2. For help configuring SMB services, click on the Help button at the upper right corner in the appliance interface. On the left sidebar, select Services. In the Contents box at the right, select Data. In the table that is displayed, select SMB. Resolving authentication issues when accessing a network-attached storage device from a Windows Server 2003 or Windows Server 2008 If you encounter authentication issues accessing a network-attached storage device after upgrading to Windows Server 2003, Windows Server 2008, see the Microsoft Support Article # at for instructions on how to correct this issue. Resolving issues when using NTLMv2 authentication on Windows Server 2008 NTLMv2 authentication is mandatory only when the LMCompatibilityLevel is set to 5 on your Windows 2008 domain controller. An LMCompatibilityLevel set to 0 to 4 means that NTLMv2 authentication is not mandatory. By default, the LMCompatibilityLevel is set to 3. If NTLMv2 authentication is mandatory on your Windows 2008 domain controller: Install the Microsoft hot fix provided in the Microsoft Support Article # at Set the AllowLegacySrvCall registry key to 1 (the Solaris CIFS service does not yet support extended security). If NTLMv2 authentication is not mandatory on your Windows 2008 domain controller, you can do one of the following: Install the Microsoft hot fix provided in the Microsoft Support Article # at On Sun ZFS Storage Appliance Configuration > Services > SMB menu, set the LAN Manager compatibility level to 2. If a STATUS_INVALID_PARAM error code is returned when a Send NTLMv2 response only authentication level is set on a Windows Server 2008, see the Microsoft Support Article #957441at for troubleshooting information. Creating a Database on a CIFS Share To create a database on the CIFS share, a UNC path must be supplied as the name of the share that meets the following criteria: 10

13 The path must include a folder with a name that corresponds to the Resource Name that was specified when the SMB protocol was configured for the CIFS share (see Figure 8). If the host name of the Sun ZFS Storage Appliance is used in the path, it must be resolvable by the Windows server. As an alternative, the DNS name or IP address of the Sun ZFS Storage Appliance can be used. Windows path expressions are case-insensitive. The trace flag 1807 must also be set. For the example used in this paper, a folder MSSQL_Data is first created on the CIFS share and the user of the Microsoft SQL Server service assigned as the owner. The database is then created using the following script: DBCC TRACEON (1807) GO CREATE DATABASE AmberRoad_Test GO ON PRIMARY LOG ON DBCC TRACEOFF (1807) GO (NAME = 'Primarydatafile', FILENAME = '\\isv-4450\mssql\mssql_data\datafile.mdf', SIZE = 1024 MB) (NAME = 'Primarylog', FILENAME = '\\isv-4450\mssql\mssql_data\logfile.ldf', SIZE = 1024 MB) 11

14 Using a Block Protocol Volume for a Microsoft SQL Server Database A block protocol, such as iscsi or Fibre Channel protocol, is designed to provide low-level access to storage volumes. A storage resource on a Sun ZFS Storage Appliance attached to a Windows server can be used to host Microsoft SQL Server database files that are to be accessed using a block storage protocol. The procedures in the following sections describe how to configure a block protocol LUN on the Sun ZFS Storage Appliance and how to configure a Microsoft Windows 2008 Server R2 to connect to an iscsi volume. iscsi protocol uses Ethernet ports as a transport mechanism, so this protocol can be implemented on the Sun ZFS Storage Appliance without additional hardware. Fibre Channel (FC) protocol is only available on the Sun ZFS Storage Appliance if additional supported FC Host Bus Adapters (HBAs) have been installed in the appliance. From an administrative perspective, the only difference between iscsi and FC protocols is how host components, either iscsi software initiators or FC HBA channels, are named. Assuming a project exists to host the file system of the block-protocol target, creating a block protocol LUN on a Sun ZFS Storage Appliance requires completing these steps as the root user: Registering the target group. Registering the name of the Windows iscsi initiator node or the World Wide Name (WWN) of the Fibre Channel host bus adapter (FC-HBA). Creating and allocating access to a LUN. Procedures in the sections below describe how this is done for block protocol LUNs accessed using ISCSI protocol and block protocol LUNs accessed using Fibre Channel protocol. Configuring iscsi Protocol Access to a LUN on the Sun ZFS Storage Appliance In the procedures in this section, the node names of servers (iscsi initiators) are registered with the Sun ZFS Storage Appliance and a group is created (iscsi initiator group). Complete these procedures as the root user. Registering an iscsi Initiator Node Name Registering an iscsi Initiator node name with the iscsi service of the Sun ZFS Storage Appliance ensures that a LUN created in this project can only be seen and mounted by the iscsi initiator. Note: To find the iscsi qualified name (IQN) for the Microsoft iscsi Software initiator, on the control panel of the Windows Server 2008 R2, select iscsi > Configuration as shown in Figure 13. The IQN will be used later in this procedure. 12

15 Figure 13. Windows Server 2008 R2 iscsi Initiator Properties 13

16 To register the iscsi Initiator node name, complete the following steps: 1. In the Sun ZFS Storage Appliance user interface, go to Configuration > Services as shown in Figure 14. Figure 14. Partial list of services on the Sun ZFS Storage Appliance 2. Under Data Services, click iscsi to configure global properties for the iscsi protocol used to access data on the Sun ZFS Storage Appliance. The Properties window shown in Figure 15 is displayed. 3. Set the property values as appropriate and click Apply. For the example described in this paper: No name server was used. No extra authentication method, such as Challenge-Handshake Authentication Protocol (CHAP) or Radius, was configured. 14

17 Figure 15. Setting iscsi protocol global properties for the Sun ZFS Storage Appliance 4. To register a new iscsi initiator node name, go to Configuration > SAN and click the iscsi Initiator tab to display the window shown in Figure 16. Figure 16. List of registered iscsi initiators 5. To set parameter values for the new iscsi initiator, click the + icon next to iscsi Initiators open the New iscsi Initiator dialog box shown in Figure 17. Figure 17. Setting iscsi Initiator parameters 15

18 6. After setting the parameter values for the new iscsi initiator, click Add. The new initiator appears in the list of registered iscsi initiators as shown in Figure 18. Figure 18. Updated list of registered iscsi initiators Creating an iscsi Initiator Group It is good practice to create an iscsi Initiator Group containing all the iscsi initiators that require access to a LUN or LUNs. For this example, an iscsi Initiator Group will be configured that contains the single initiator MSSQL. If the Microsoft SQL Server is run under a cluster at some future time, other nodes can be added to the group without affecting access to the LUN by the MSSQL node. To create an iscsi Initiator Group, complete these steps: 1. Place the cursor over the entry for MMSQL in the list of iscsi Initiators. A icon appears to the left of the entry as shown in Figure Drag the icon symbol to the right. If a new group is to be created, drop it into the box with the + icon that appears at the bottom of the iscsi Initiator Groups list as shown in Figure 19. A new group is created with the name initiators-n, where n is an integer. If the initiator is to be added to an existing iscsi Initiator group, drop it on the entry for that group. Figure 19. Creating an iscsi Initiator Group 16

19 3. Place the cursor over the entry for the new group. A set of icons will appear to the right of the entry as shown in Figure 20. Figure 20. Displaying editing icons for the new iscsi Initiator Group 4. To edit the Initiator Group name, click on the pencil icon and enter a name appropriate for the deployment as shown in Figure 21. Figure 21. Renaming the iscsi Initiator Group 5. Click OK. The entry for the initiator group will display the new name. 17

20 Configuring Fibre Channel Protocol Access to a LUN on the Sun ZFS Storage Appliance In the procedures in this section, the Fibre Channel ports are identified and grouped so that LUNs can be mapped to the group allowing them to be presented to appropriate servers over a Fibre-Channel SAN. Fibre Channel initiators (servers) are then identified and grouped into initiator groups to allow fine-grained access permissions to be applied. These procedures must be completed by the root user. Creating a Fibre Channel Target Group To create a Fibre Channel Target Group that contains the Fibre Channel ports for the Sun ZFS Storage Appliance, complete the steps below: 1. Go to Configuration > SAN. The Targets window showing a list of Fibre Channel ports is displayed as shown in Figure 22. In this example, two FC ports have been discovered by the Sun ZFS Storage Appliance. 2. Place the cursor over an entry for one of the ports. A icon appears to the left of the entry as shown in Figure 22. Figure 22. Displaying the icon used to move Fibre Channel port to a group 3. Drag the icon symbol to the right. If a new group is to be created, drop it into the box with the + icon that appears at the bottom of the Fibre Channel Target Group list as shown in Figure 23. A new group is created with the name targets-n, where n is an integer. If the port is to be added to an existing Fibre Channel Target Group, drop it on the entry for that group. Figure 23. Dragging a Fibre Channel port to a new Fibre Channel Target Group 18

21 4. Place the cursor over the entry for the new group. A set of icons will appear to the right of the entry as shown in Figure 24. Figure 24. Displaying the editing icons for the new Fibre Channel Target Group 5. To edit the Fibre Channel Target Group name, click on the pencil icon and enter a name appropriate for the deployment as shown in Figure 25. Figure 25. Editing the FC Target Group Name 6. Select any additional Fibre Channel Ports to be added to the group. 7. Click OK. The changes will appear on the Targets window. Registering the Fibre-Channel Initiators In this procedure, each Fibre-channel initiator is registered by assigning it a symbolic name (alias), and multiple initiators are grouped to form a logical entity such as a server or a cluster of servers. 1. Go to Configuration > SAN and click the Initiators tab as shown in Figure 26. Figure 26. Selecting the Fibre Channel Initiator window 19

22 2. Click the + icon next to Fibre Channel Initiators to display the dialog box shown in Figure 27. Any Fibre Channel ports that have not been assigned aliases are shown at the bottom of the dialog box Figure 27. Assigning aliases to new Fibre Channel Initiator ports 3. Click on the WWN for a port to populate the World Wide Name box at the top. 4. Provide an appropriate alias for the FC port and click OK. The Fibre Channel Initiator ports will now be referenced by alias in the Sun ZFS Storage Appliance GUI (see Figure 28). Note: One commonly-used initiator naming scheme is hostname-hba number-port number. Creating a Fibre Channel Initiator Group To create a Fibre Channel Initiator Group, complete the steps below: 1. Place the cursor over the entry for one of the initiator aliases. A icon appears to the left of the entry as shown in the top view in Figure Drag the icon symbol to the right. If a new group is to be created, drop it into the box with the + icon that appears at the bottom of the Fibre Channel Initiator Groups list as shown in the bottom view in Figure 28. A new group is created with the name initiators-n, where n is an integer as shown in Figure 29. If the initiator is to be added to an existing Fibre Channel Initiator Group, drop it on the entry for that group. Figure 28. Creating a new Fibre Channel Initiator Group 20

23 Figure 29. Creation of new FC Initiator Group 3. To edit the Initiator Group name, click on the pencil icon and enter a name appropriate for the deployment as shown in Figure 30. Select any additional Fibre Channel Initiators to be added to the group. Figure 30. Renaming the Fibre Channel Initiator Group and adding Fibre Channel Initiators to the group 4. Click OK. Figure 31 shows the group has been renamed MSSQL-X4450 and an additional FC Initiator alias has been added to the group. Figure 31. MSSQL-X4450 FC Initiator Group with FC initiator group members listed 5. Click Apply for the changes to take effect. Creating a New Block Protocol LUN In this procedure, a block protocol LUN is mapped to an iscsi or Fibre Channel target group to enable access by an initiator group. The example shows creating a new block protocol LUN to be accessed by an initiator group using iscsi protocol. 21

24 To create a new block protocol LUN, complete the steps below: 1. Go to Shares > Shares and select the MS_SQLSSERVER project as shown in Figure 32. Figure 32. Viewing the Shares window for the MS_SQLSERVER project 2. Click the + icon on the LUNS tab to open the Create LUN dialog box shown in Figure Enter values for the Name of the target LUN and the Volume Size. 4. Modify the Volume Block Size as needed. 5. Select the Initiator Group that is to be given access. 6. If desired, select a specific Target Group to identify which block protocol is used to present this LUN. For the example in this paper, the Target Group was set to iscsi-targets as shown in Figure 33. Note: It is assumed that iscsi protocol is used to present LUNs for the example in this paper. Figure 33. Creating and setting parameters for a block protocol LUN 7. Click Apply. The new LUN is displayed on the Shares window of the project MS_SQLSERVER. 22

25 8. Review the properties of the LUN and modify them as needed by moving the cursor over the entry for the LUN on the Shares window and clicking the pencil symbol that appears at the right of the entry. The General properties for the LUN are shown in Figure 34. Figure 34. Viewing properties for a block protocol LUN 23

26 Configuring the Windows Server to Connect to an External iscsi Volume This section describes how to configure a Microsoft Windows 2008 Server R2 to connect to an external iscsi volume. The following steps are required: 1. Configure the Microsoft iscsi Software Initiator bundled with the Microsoft Windows 2008 Server R2. Note: For instructions for configuring the Microsoft Windows 2008 Server R2 to use Fibre- Channel protocol block access, refer to documentation provided by the HBA manufacturer. 2. Create a volume using the Initialize and Convert Disk Wizard (or the command line tool diskpart.exe). 3. Create a file system using the New Volume Wizard (or the command line tool format.exe). These steps are described in more detail in the following sections. Configuring the Microsoft iscsi Software Initiator The Microsoft iscsi Software Initiator is configured using a collection of property windows accessed through tabs as shown in Figure 35. Figure 35. Accessing Microsoft iscsi Software Initiator properties 24

27 To configure the Microsoft iscsi Software Initiator, complete these steps: 1. Select the Discovery tab and then, under Target Portals, click Add Portal to display the Add Target Portal dialog box shown in Figure 36. Figure 36. Adding an iscsi target portal to the Microsoft iscsi Software Initiator 25

28 2. Enter the IP address of the Sun ZFS Storage Appliance. Keep the default iscsi port setting Click OK. The result of registering the Sun ZFS Storage Appliance target portal is shown in Figure 37. Figure 37. Sun ZFS Storage Appliance registered in the Microsoft iscsi Software Initiator 26

29 3. Select the Targets tab to list the iscsi volumes available on registered hosts as shown in Figure 38. A status of Inactive indicates that an iscsi volume cannot currently be mounted. Figure 38. The iscsi target in the project MS_SQL_SERVER_iscsi identified in the Microsoft iscsi Software Initiator 4. To change the status of the iscsi target to Connected, click Log on. The Log On to Target dialog box is displayed. Note: The target is now available as a disk in the Windows Disk Management utility. 5. Select the appropriate options. Select the first option to make the volume a persistent target. This option is appropriate for an iscsi volume that is designated to host the datafiles of a Microsoft SQL Server database. It is shown as selected in Figure 39 for the example in this paper. Select the second option to make use of multiple network paths to provide fault tolerance. This option requires at least two network interface cards (NICs) attached to different subnets on the Sun ZFS Storage Appliance and has not been selected for the example in this paper. 27

30 Figure 39. Attaching the iscsi target volume in the Microsoft iscsi Software Initiator 6. If CHAP security was enabled for this volume on the Sun ZFS Storage Appliance, click Advanced to open a dialog box in which the CHAP authentication secret can be entered. CHAP was not enabled for this example. 7. If an iscsi volume needs to be dismounted (removed from the list of available disks in Disk Management), click Details to display the properties of the selected iscsi target and then select the Sessions tab as shown in Figure 40. Click Log off to remove the iscsi target volume from the local host. Note: This operation is required if the size of the target is to be modified or if a rollback from a snapshot is to be performed on the Sun ZFS Storage Appliance. 28