HP P4000 DSM for MPIO Deployment Guide HP Part Number: AX696-96111 Published: September 2011 Edition: 1
© Copyright 2011, Hewlett-Packard Development Company, L.P.
Description of the HP P4000 DSM for Microsoft MPIO The HP P4000 DSM for Microsoft MPIO provides enhanced MPIO functionality as follows: • Automatic creation of an I/O path to each storage system in the cluster on which the volume resides, plus a path for the administrative connection. • Improved performance architecture over native MPIO solutions: • ◦ Read I/Os are always serviced by a storage system that holds a copy of the data being requested.
If currently using the HP DSM for MPIO, then upgrade to the latest version. Recommended uses for HP DSM for MPIO: • For maximum possible performance for specified configurations. • With Multi-Site SAN storage clusters, the HP DSM for MPIO with site preference is recommended, particularly if the inter-site link is significantly slower than local access. This configuration will ensure that reads are performed with a local replica when one is available.
Windows Server 2008 and Server Core option • 32-bit or 64-bit version of Windows Server 2008, the Server Core, Windows Server 2008 R2, or R2 Server Core installations • The Microsoft iSCSI Initiator, which comes installed with all Windows Server 2008 and the Server Core installation • The Microsoft Multipath IO optional component installed If installing the HP DSM for MPIO into an existing Microsoft cluster 1. 2. Move all cluster resources and related file shares to one system that will stay active.
The setup begins. You will see nothing until after a minute or two, when the server reboots. 3. When the server is back up, check \Windows\dsminstall.log for errors. Connecting volumes with MPIO Once the HP DSM for MPIO or Microsoft DSM is installed on the server, all iSCSI volume connections made to an iSCSI SAN will attempt to connect with the DSM. You do not need to configure the multiple I/O paths manually.
Figure 2 Configuring advanced settings for multiple NICs 9. Click OK to close the Advanced Settings dialog. 10. Click OK again to finish logging on. 11. If you want to set the MPIO load balancing policy, see “Setting the Microsoft DSM MPIO load balancing policy” (page 8). 12. If you have multiple NICs, repeat steps 3 through 11 for the additional storage NICs.
Figure 3 Multi-site SAN VIPs with MPIO Setting the Microsoft DSM MPIO load balancing policy When you connect application servers to volumes, you can also set the MPIO load balancing policy in the iSCSI Initiator. Supported load balancing options Only two load balancing options are supported, Fail Over and Round Robin. For the Microsoft DSM with Windows 2003 Server, only the Fail Over Only option is supported. • Fail Over Only – Also called active/passive MPIO.
Figure 5 HP DSM for MPIO with two NICs in the server and Round Robin MPIO load balancing Figure 6 Microsoft DSM with two NICs in the server and Fail Over MPIO load balancing Figure 7 Microsoft DSM with two NICs in the server and Round Robin MPIO load balancing NOTE: Be sure to follow the steps below to set the MPIO load balancing policy. Similar options are available for Multiple Connected Session (Windows 2008) or Session Connections (Windows 2003).
4. Click the MPIO button or tab. If the MPIO button or tab is not available, MPIO is not installed and enabled. 5. 6. 7. From the Load balancing policy drop-down list, select either Fail Over Only or Round Robin. Click OK. Click OK. Troubleshooting MPIO Verifying HP DSM for MPIO operations After logging on to a volume via iSCSI, the HP DSM for MPIO automatically builds a data path to each storage system in the cluster and one administrative path.
Figure 9 Multiple paths ensure continued I/O in event of path failure When the problem with the I/O path is repaired, the HP DSM for MPIO reconnects an I/O path to the storage system, thus restoring optimized performance and fault tolerance. Verifying Microsoft DSM operations If you see two devices that are exactly the same listed in the Disk Manager or My Computer, you may not have MPIO installed or you may not have logged using MPIO.
Performing a silent uninstall for the Windows 2008 Server Core option IMPORTANT: 1. 2. Uninstalling the HP DSM for MPIO requires a reboot of the system. Open a command prompt and use the cd command to navigate to setup.exe in the installation media. Type the following command: setup /removeonly /s /f1”.\uninst.iss” 3. 4. 12 The uninstall begins. You will see nothing until after a minute or two, when the server reboots. When the server is back up, check \Windows\dsminstall.log for errors.
