C H A P T E R 1

Introduction

This Best Practices Manual describes the use of Sun StorEdge 3510 FC arrays and Sun StorEdge 3511 SATA arrays, as well as the use of their corresponding expansion units. It complements the Sun StorEdge 3000 Family Installation, Operation, and Service Manual for these products.

This manual gives a high level overview of Sun StorEdge 3510 FC arrays and Sun StorEdge 3511 SATA arrays, and presents several sample storage solutions for entry-level, mid-range, and enterprise servers. Use these solutions as-is or tailor them to fit your exact needs. Examples of customization opportunities include adding disks, enclosures and software, or even combining configurations. Choosing the solution that best matches your particular environment will provide the best results.

Executive Summary

Before reading the detailed information in this document, review this high-level overview of factors that affect the reliability, availability, and serviceability (RAS) of not only your storage arrays but your system as a whole.

RAS Features of Sun StorEdge 3000 Family Arrays

The following subjects are described in more detail in this document:

Dual-controller configurations

Use dual-controller arrays to avoid a single point of failure. A dual-controller FC array features a default active-to-active controller configuration. This configuration improved application availability because, in the unlikely event of a controller failure, the array automatically fails over to a second controller, resulting in no interruption of data flow.

Logical drives

The best practice for creating logical drives is to add them evenly across the primary and secondary controllers. With at least one logical drive assigned to each controller, both controllers are active. This configuration is known as an active-active controller configuration and allows maximum use of a dual-controller array's resources.

Power redundancy

To ensure power redundancy, connect the two power modules to two separate circuits, such as one commercial circuit and one UPS.

FC cabling to both controllers

When attaching FC cables for LUNs configured with redundant paths, make sure one cable is connected to a channel on the upper controller and the other cable is connected to a different channel on the lower controller. Then, if multipathing software is configured on the host, a controller can be hot-swapped in the event of failure without losing access to the LUN.

Cache optimization

The RAID array's cache optimization mode determines the cache block size used by the controller for all logical drives:

For sequential optimization, the cache block size is 128 Kbyte.

For random optimization, the cache block size is 32 Kbyte.

User-configurable stripe size

When you create a logical drive, you can replace the default stripe size with one that better suits your application.

For sequential optimization, available stripe size choices include 16 Kbyte, 32 Kbyte, 64 Kbyte, 128 Kbyte, and 256 Kbyte.

For random optimization, available stripe size choices include 4 Kbyte, 8 Kbyte, 16 Kbyte, 32 Kbyte, 64 Kbyte, 128 Kbyte, and 256 Kbyte.

Cable to expansion units so there is no single point of failure

Representative sample cabling diagrams are presented in this document for a number of expansion unit configurations.

Additional RAS Features You Can Use With FC and SATA Arrays

Even with all the Sun StorEdge 3000 Family's built-in RAS features and the best practices described in this document, single points of failure can still occur. For instance, some rare hardware failures--a midplane or bus failure, for instance--could conceivably disable both controllers of an active-active configuration. It is prudent to use other RAS best practices, such as traditional backup-and-restore strategies and host-based multipathing and clustering, to ensure network reliability. Sun Microsystems makes available a wide variety of white papers and product documentation that provide specific information to help you plan or upgrade the architecture of your systems.

The Solaris 10 operating system provides built-in multipathing support for FC storage devices. Consider upgrading to the Solaris 10 operating system in order to take advantage of this multipath support. This functionality is described in the Solaris Fibre Channel and Storage Multipathing Administration Guide:

http://docs-pdf.sun.com/819-0139/819-0139.pdf

Earlier versions of the Solaris operating system do not contain this built-in multipathing support. Sun SAN Foundation Suite software, including Sun StorEdge Traffic Manager, provides some of this functionality. For more information, refer to the Sun StorEdge SAN Foundation Software 4.4 Guide to Documentation:

http://docs-pdf.sun.com/817-3670-12/817-3670-12.pdf

A feature article on Sun's BigAdmin System Administration Portal, "Backup, Restore, and Disaster Recovery on a System With Zones Installed" describes useful security procedures that take advantage of features in the Solaris operating system and in third-party backup software, including some useful links to other system administration documentation:

http://www.sun.com/bigadmin/features/articles/backup_zones.html

Another useful feature article, "Installing and Configuring Sun Cluster 3.1 09/04 Software for High-Availability Applications" provides an excellent overview of strategies "to design an environment where services can migrate between individual servers so that a reboot of a single machine never causes a service downtime. Sun's solution to architecting these highly available services is combining the software product, Sun Cluster, with the appropriately sized servers, shared storage, and network topology." It also describes the interaction of Sun Cluster environments with Volume Manager software, and contains an excellent list of related links:

http://www.sun.com/bigadmin/features/articles/install_cluster.html

A useful IDC white paper sponsored by Sun Microsystems, "Meeting Business Objectives Through Unified and Simplified Storage," describes a wide spectrum of present and emerging best practices, including tiered storage; unified data replication; and automated provisioning, expansion, and data protection tasks across heterogeneous storage systems. While the specific business cases referenced in this article include some software features currently found in higher-end arrays than the Sun StorEdge 3000 family, this functionality is rapidly migrating to workgroup storage arrays:

http://www.sun.com/storage/white-papers/idc_virtualization.pdf

A more basic article for less experienced system administrators who are setting up file servers, "Introduction to Creating a File Server," provides a useful overview of mirroring boot disks and using advanced RAID levels to distribute data across multiple physical disks in an array:

http://www.sun.com/bigadmin/features/articles/file_server.html

Performance issues and strategies are described in considerable detail in "Storage System Bottlenecks and Their Solutions:"

http://www.sun.com/storage/white-papers/storage_bottlenecks.pdf

The objective of this white paper is to enable readers to:

increase end-to-end performance by taking advantage of multi-threaded I/Os to the storage system controller and its drives

deliver predictable storage system performance by matching the storage system configuration to workload requirements

increase storage system throughput by distributing a workload across the storage system

Differences Between Sun StorEdge 3510 FC Array and Sun StorEdge 3511 SATA Array

The Sun StorEdge 3510 FC array is a next-generation Fibre Channel storage system designed to provide direct attached storage (DAS) to entry-level, mid-range, and enterprise servers, or to serve as the disk storage within a storage area network (SAN). This solution features powerful performance and reliability, availability and serviceability features using modern FC technology. As a result, the Sun StorEdge 3510 FC array is ideal for performance-sensitive applications and for environments with many entry-level, mid-range, and enterprise servers, such as:

Internet

Messaging

Database

Technical

Imaging

The Sun StorEdge 3511 SATA array is a Fibre Channel array that uses Serial ATA drives. These arrays are best suited for inexpensive secondary storage applications that are not mission-critical, where higher capacity drives are needed, and where lower performance and less-than 7/24 availability is an option. This includes near-line applications such as:

Information lifecycle management

Content addressable storage

Backup and restore

Secondary SAN storage

Near-line DAS storage

Static reference data storage

Note - Procedures described for configuring Sun StorEdge 3510 FC arrays and Sun StorEdge 3511 SATA arrays are the same except where noted in this manual.

Sun StorEdge 3511 SATA expansion units can be connected to Sun StorEdge 3510 FC arrays, either alone or in combination with Sun StorEdge 3510 FC expansion units. Up to five expansion units can be used in this configuration. For instance, you might wish to use the Fibre Channel drives for primary online applications and the SATA drives for secondary or near-line applications within the same RAID array. For an example of such a configuration, see Combining Sun StorEdge 3510 FC Arrays and Sun StorEdge 3511 SATA Expansion Units.

Sun StorEdge 3510 FC arrays use Fibre Channel (FC) disk drives, and are supported by Sun Microsystems in primary online applications as well as secondary and near-line applications. Sun StorEdge 3511 SATA arrays are supported by Sun Microsystems in either near-line applications, such as backing up and restoring data, or secondary applications such as static storage. Sun StorEdge 3510 FC arrays can be used in multipath and multi-host configurations, but they are not designed to be used in primary online applications or as boot devices.

Caution - Although the two products are very similar in appearance and setup, the configurations have very important differences. While the Sun StorEdge 3510 FC array can be used for all applications, the Sun StorEdge 3511 SATA array cannot, and inappropriate use in applications for which the Sun StorEdge 3510 FC array was designed may result in the loss of data and/or data access.

Refer to the Installation, Operation, and Service manual for your array for more detailed information about differences between Sun StorEdge 3510 FC arrays and Sun StorEdge 3511 SATA arrays. Refer to the release notes for your array for information about additional disk capacities that may be available for your array.