9.5 HP P4000 DSM for MPIO Deployment Guide (AX696-96111, September 2011)

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.
◦
◦ Write I/Os are always serviced by a storage system that receives a copy of the data.
Remaining copies (replicas) of the data are forwarded to the appropriate storage system
based on the data protection level of the volume.
• The ability to build a robust, fault-tolerant solution because an I/O path is built to every storage
system in the cluster. For example, in a cluster with five storage systems, HP DSM for
MPIO-connected volumes have six iSCSI MPIO connections to the SAN, one for each storage
system and one for the administrative connection. Five of the six connections could go offline,
and I/O would still be serviced.
The HP DSM for MPIO supports connecting multiple NICs in the application server to the SAN.
Configuring with multiple NICs improves fault-tolerant physical network connections in the server.
The HP DSM for MPIO can be used in a Multi-Site SAN with one or more subnets. In this configuration,
the HP DSM for MPIO will only build I/O paths to the storage systems that are in the same subnet as
the application server. Alternatively, you can assign an application server to a site. Application servers
assigned to a site connect only to storage systems in the same site. Both of these configurations permit
higher performance and lower network utilization by reducing the amount of I/Os that traverse the
WAN link.
NOTE: Refer to the instructions specific to Multi-Site SAN configurations in the rest of this chapter.
You can also refer to the HP P4000 Multi-Site HA/DR Solution Pack User Guide, available on the HP
P4000 Management Software DVD or on the HP P4000 Manuals page of the HP Business Support
Center website.
http://www.hp.com/support/manuals
In the Storage section, navigate to Disk Storage Systems→P4000 SAN Solutions→HP LeftHand P4000
SAN Solutions or HP StorageWorks P4000 G2 SAN Solutions, depending upon your product.
Using Microsoft DSM
Beginning with SAN/iQ software Version 9.0, you can use Microsoft DSM on your application servers.
For additional information about the Microsoft DSM, see the MPIO white paper available from the
Microsoft website:
http://www.microsoft.com/download/en/details.aspx?id=9787
When setting up the MPIO load balancing policy, use only the Fail Over Only or Round Robin options.
For more information, see “Setting the Microsoft DSM MPIO load balancing policy” (page 8).
Using VMware ESX Server native MPIO
With VMware ESX, use the native ESX MPIO. For more information, see http://h20195.www2.hp.com/
V2/GetDocument.aspx?docname=4AA3-0261ENW.
Best Practices
If MPIO is not required, then do not install the HP DSM for MPIO or do not enable the the Microsoft
MPIO service.
Description of the HP P4000 DSM for Microsoft MPIO 3