SVC with Infinidat Storage Configuration Guide

Content

This document should be used by anyone using the IBM Spectrum Virtualize family of products with the INFINIDAT InfiniBox.

You should review this guide together with suitable SVC Infocenter information and Best Practices from the Redbooks.

https://www.ibm.com/support/knowledgecenter/STPVGU
http://www.redbooks.ibm.com/portals/storage

Note: IBM Spectrum Virtualize Products include Spectrum Virtualize Software, SAN Volume Controller - SVC, and suitable IBM Storwize controllers. In this document all will be referred to as SVC.

Configuring the Infinidat Infinibox
This portion of the document covers the necessary configuration for using Infinibox with an SVC cluster.

Support for models of Infinibox

Please see the IBM System Storage Interoperation Center web site at https://www.ibm.com/systems/support/storage/ssic/ for full and up-to-date details.

Initial Support from; firmware levels of Infinibox and SVC.

Concurrent maintenance on Infinibox

Concurrent firmware upgrades are supported as per InfiniBox procedures.

Target Ports

For SVC each World-Wide Node Name (WWNN) presented by external storage may have up to a maximum of sixteen World-Wide Port Names (WWPNs) associated with it.
 InfiniBox is an active-active-active system with three controllers presented as a single WWNN, and Spectrum Virtualize clusters are formed from pairs of nodes, so the number of configured targets should be the maximum amount divisible by both two and three, i.e. twelve. These ports should be equally divided between the three InfiniBox nodes and across either two or four fibre-channel fabrics. Using six ports rather than twelve may be appropriate in certain situations where an InfiniBox system is partially virtualized.

Note that all ports have equal priority on InfiniBox; there is no concept of preferred nodes or ports. All configured InfiniBox ports within each SAN fabric should be visible by all configured Spectrum Virtualize ports within the fabric. Standard best practice regarding the distribution of ports between hosts, storage and inter-node connections should be followed.

See Latest; Vx.x Configuration Limits and Restrictions for IBM System Storage SAN Volume Controller

Controller splitting

The InfiniBox controller may be shared with other hosts, provided SVC has sole access to the LUNs presented to it as mdisks. However SVC will be unaware of the additional traffic and performance.

While a single InfiniBox may be shared amongst multiple SVC clusters, this is strongly discouraged. Separate I/O groups within a single cluster will provide better results.

Quorum disks on Infinibox

The SAN Volume Controller cluster can use mdisks that are presented by the InfiniBox storage system as quorum disks. To maintain availability for the cluster, ideally each quorum disk should reside on a separate disk subsystem where possible.

Easy Tier with an InfiniBox storage system

Easy Tier’s data placement mechanisms conflict with those of InfiniBox, resulting in sub-optimal performance. InfiniBox should be avoided for use in multi-tier pools and Easy Tier should be disabled for single-tier pools ( svctask chmdiskgrp -easytier off <mdiskgrp id> ).

Thin Provisioning

Spectrum Virtualize supports the careful use of thin provisioning on managed storage; volumes presented from InfiniBox may be thin-provisioned as long as sufficient capacity is available for growth

If there is a requirement to expand the used storage on demand, then new managed disks should be allocated to the pool as required. Resizing managed disks while they are in use is not supported. Because InfiniBox balances data across its media there is no requirement to re-balance data when a Spectrum Virtualize pool is expanded.

Additional Configuration Suggestions

Choosing an Extent Size;

Because InfiniBox systems can provide several petabytes of storage, care should be taken to ensure that the extent size chosen does not limit the capacity which can be virtualised.

Choosing Numbers and Sizes of Volumes;
When creating volumes on InfiniBox, please be aware that capacities should be a multiple of the extent size as defined in the Spectrum Virtualize software. Extent sizes are defined in binary units so binary units should be used when defining volumes on InfiniBox.

Unlike traditional RAID-based systems, there are no physical RAID arrays in InfiniBox so the principle of 1 array = 1 mdisk does not apply. Individual volumes within InfiniBox have no affinity to a particular node or port and round-robin path selection is supported. Consequently, any number and size of volume may be used, subject to the limits imposed by the Spectrum Virtualize software.

Nevertheless, it is preferable to use a number of volumes that can be distributed evenly amongst the number of paths available and in most circumstances, 48 volumes of equal capacity should be used.

Further discussion on the topic may be found in the “Round Robin Path Selection” section of the Redbook IBM System Storage SAN Volume Controller and Storwize V7000 Best Practices and Performance Guidelines

Flash Copy Grain Sizes

InfiniBox uses a 64K allocation unit. For optimum performance, a grain size of 64 KB should be chosen when creating Flash Copies.