User guide

Technical white paper | HP Enterprise Virtual Array Storage and VMware vSphere 4.x and 5.x configuration best practices
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• When the EVA is in degraded mode, avoid using VAAI operations.
• When using VAAI on Vdisks that are in snapshot, snapclone, mirror clone or continuous access relationships VAAI
performance may be throttled.
• Minimize the number of concurrent VAAI clone and/or zeroing operations to reduce the impact on overall system
performance.
• Ensure the HP EVA Storage is configured with an adequate number of drives when using VAAI. Refer to Table 8 for
guidance.
• Using two iSCSI GbE ports at the array and two NICs on the ESX host provides the most flexible option to achieve the right
balance of ease of configuration, high availability and performance for the 10GbE iSCSI Module configuration options.
• For the 1GbE iSCSI Module configuration option, using Static discovery to limit the number of iSCSI targets used per GbE
port to 1 can help achieve increased high availability and performance at the cost of ease of configuration.
• Use ESXi 5.5 UNMAP reclaim unit of 480 for EVA4400/EVA8400 (assumes 1MB block size).
• Use ESXi 5.5 UNMAP reclaim unit of 1280 for P63xx/P65xx (assumes 1MB block size).
• Invoke only a single instance of VMware space reclamation against an array or datastore.
How do I maintain the availability of Command View EVA deployed in a VM?
• HP recommends deploying Command View EVA (CV EVA) on the local datastore of a vSphere server. However, if a SAN-
based deployment s required, then load CV EVA on to multiple EVAs to ensure that the management interface remains
available. If CVA EVA were deployed on a single VM, the management interface would be lost if the particular EVA became
inaccessible.
Summary
In most environments, the best practices highlighted in this document can help you reduce configuration time and improve
storage performance. However, as with all best practices, you must carefully evaluate the pros and cons of the
recommendations presented herein and assess their value in your particular environment.
In addition to serving as a reference guide for anyone configuring an EVA-based SAN in conjunction with vSphere 4.x/5.x,
this document also provides valuable information about the latest VMware technologies, such as the multi-pathing storage
stack.
Glossary
Term
Description
1 GbE iSCSI Module
Built-in 1 GbE iSCSI Module for HP EVA P6000. Also referred to as iSCSI Module
10 GbE iSCSI Module
Built-in 10 GbE iSCSI Module for HP EVA P6000. Also referred to as iSCSI/FCoE Module
Array
In the context of this document, an array is a group of disks that is housed in one or more disk enclosures. The
disks are connected to two controllers running software that presents disk storage capacity as one or more
virtual disks. The term “array” is synonymous with storage array, storage system, and virtual array.
Controller firmware
The firmware running on each controller within the array manages all aspects of array operation, including
communications with Command View EVA.
Default disk group
The default disk group is the disk group created when the array is initialized. This group must contain a
minimum of eight disks, with its maximum size being the number of installed disks.
Disk group
A disk group is a named group of disks that have been selected from disks that are available within the array.
One or more virtual disks can be created from a disk group.
DR group
A data replication (DR) group is a logical group of virtual disks that is part of a remote replication relationship
with a corresponding group on another array.
ESX/ESXi
ESX/ESXi is the hypervisor component of VMware vSphere.