034-2652_Cvr 8/17/04 4:42 PM Page 1 Xsan Getting Started Includes instructions for setting up shared volumes on a storage area network
LL2652.book Page 2 Wednesday, July 28, 2004 3:45 PM Apple Computer, Inc. © 2004 Apple Computer, Inc. All rights reserved. The owner or authorized user of a valid copy of Xsan software may reproduce this publication for the purpose of learning to use such software. No part of this publication may be reproduced or transmitted for commercial purposes, such as selling copies of this publication or for providing paid for support services. The Apple logo is a trademark of Apple Computer, Inc.
LL2652.
LL2652.
About This Guide Preface LL2652.book Page 5 Wednesday, July 28, 2004 3:45 PM This guide shows how to set up your first Xsan volumes on a storage area network. Use the instructions in this guide to plan and set up shared volumes of storage on a storage area network (SAN). Using this Guide For an overview of Xsan and storage area networks, read Chapter 1. To review hardware, software, and network requirements, and to see tips for planning your SAN volumes, read Chapter 2.
LL2652.
LL2652.book Page 7 Wednesday, July 28, 2004 3:45 PM 1 Introduction to Xsan 1 This chapter gives you an overview of Xsan and how you can use it to provide fast, shared storage on a storage area network (SAN). If you want to set up an Xsan volume on a storage area network right now, skip to Chapter 2, “Before You Begin,” on page 15.
LL2652.book Page 8 Wednesday, July 28, 2004 3:45 PM Xsan and Storage Area Networks A storage area network is a way of connecting computers to storage devices that gives users very fast access to files and gives administrators the ability to expand storage capacity as needed without interrupting users.
LL2652.book Page 9 Wednesday, July 28, 2004 3:45 PM Shared SAN Volumes Users and applications see shared SAN storage as local volumes. Xsan volumes are logical disks made up of groups of RAID arrays. The elements you combine to create an Xsan volume are described under “How Xsan Storage Is Organized” on page 10. Controllers and Clients When you add a computer to an Xsan SAN, you specify whether it will play the role of client, controller, or both.
LL2652.book Page 10 Wednesday, July 28, 2004 3:45 PM How Xsan Storage Is Organized Users work with an Xsan volume the same way they use a local disk. What they don’t see is that the SAN volume actually consists of numerous physical disks combined on several levels using RAID techniques. The following illustration shows an example of how disk space provided by individual drive modules in Xserve RAID systems is combined into a volume that users see as a large local disk.
LL2652.book Page 11 Wednesday, July 28, 2004 3:45 PM One of your first tasks when setting up a SAN volume is to prepare LUNs. If the two RAID 5 arrays on a new Xserve RAID are not right for your application, you can use RAID Admin to create arrays based on other RAID schemes. For help choosing schemes for your LUNs, see “Choosing RAID Schemes for LUNs” on page 20. For example, the illustration on page 10 shows four Xserve RAID systems hosting two arrays each.
LL2652.book Page 12 Wednesday, July 28, 2004 3:45 PM The following screen image shows how LUNs, storage pools, and volumes appear as you organize them in the Xsan Admin application. This example shows a SAN named “Test SAN” with a single shared volume named “SanVol.” Storage for the volume is provided by two storage pools, “Pool1” and “Pool2,” each based on a single LUN. Each of the LUNs is a 3-disk RAID 5 array on an Xserve RAID using 115 GB drive modules.
LL2652.book Page 13 Wednesday, July 28, 2004 3:45 PM How Xsan Utilizes Available Storage Xsan stores both user files and file system data on SAN volumes, and stripes data across the LUNs in a volume for better performance. Metadata and Journal Data Xsan records information about the files in an Xsan volume using metadata files and file system journals.
LL2652.book Page 14 Wednesday, July 28, 2004 3:45 PM Expanding Storage You can add free space to an Xsan volume without interrupting users or applications that rely on the volume for access to files. There are two ways to add storage to a volume: • Add Xserve RAID systems (new LUNs) to existing storage pools • Add new storage pools to volumes The first method requires you to unmount and remount the volume on clients.
LL2652.book Page 15 Wednesday, July 28, 2004 3:45 PM 2 Before You Begin 2 Review the planning tips and the hardware, software, and network requirements in this chapter before you set up your first SAN volume.
LL2652.book Page 16 Wednesday, July 28, 2004 3:45 PM Supported Storage Devices This guide and the Xsan Administrator’s Guide assume you are using Xserve RAID systems for your storage devices. Important: Be sure to install the latest firmware update on your Xserve RAID systems before you use them with Xsan.
LL2652.book Page 17 Wednesday, July 28, 2004 3:45 PM Ethernet TCP/IP Network Computers in the SAN must also be connected to an Ethernet network. Xsan uses this network instead of the Fibre Channel network to transfer file system metadata, reserving the Fibre Channel connections for actual file contents.
LL2652.book Page 18 Wednesday, July 28, 2004 3:45 PM Planning Your SAN Volumes It’s easy to add storage to an existing Xsan volume, but reorganizing a volume after you set it up is not so simple. So, it’s important to plan the layout and organization of your SAN and its storage before you set it up.
LL2652.book Page 19 Wednesday, July 28, 2004 3:45 PM Planning Considerations and Guidelines The following paragraphs might help you make some of your SAN design decisions. How Much Storage? Because it’s easy to add storage to an Xsan SAN without interrupting user work, you only need to decide on an adequate starting point. You can then add storage as needed. Note that the number of Xserve RAID systems you use affects not only available space but also SAN performance.
LL2652.book Page 20 Wednesday, July 28, 2004 3:45 PM • Store user files, file system metadata, and journal data on separate storage pools, and create these storage pools using LUNs from different RAID controllers. • Try to keep the SAN’s Ethernet network free from other traffic. Use a router to isolate the network used by the SAN from a company intranet or the Internet, or better, use a second Ethernet network (including a second Ethernet card in each SAN computer) for the SAN.
LL2652.book Page 21 Wednesday, July 28, 2004 3:45 PM Xserve RAID supports all popular RAID levels. Each RAID scheme offers a different balance of performance, data protection, and storage efficiency, as summarized in the following table.
LL2652.book Page 22 Wednesday, July 28, 2004 3:45 PM To provide high performance, Xsan uses the RAID 0 scheme to stripe data across the LUNs in a storage pool. This requires that the LUNs in the pool be the same size. If you set up a storage pool using LUNs of different sizes, Xsan uses available space on each LUN equal to the capacity of the smallest LUN. If the LUNs vary in size, this can result in wasted capacity.
LL2652.book Page 23 Wednesday, July 28, 2004 3:45 PM If high availability is important, you should use at least two controllers, one as the primary controller and one as a standby. You can specify additional controllers as needed, and set their failover priorities to determine the order in which they are tried if the primary controller stops responding.
LL2652.book Page 24 Wednesday, July 28, 2004 3:45 PM Connecting Computers and Storage Devices Before you set up your Xsan SAN, connect client computers, controller computers, and storage devices to the SAN’s Fibre Channel and Ethernet networks. Make sure your networks meet the requirements summarized under “Fibre Channel Fabric” on page 16 and “Ethernet TCP/IP Network” on page 17.
LL2652.book Page 25 Wednesday, July 28, 2004 3:45 PM Using the Xsan Admin Application You use the Xsan Admin application to set up and manage Xsan volumes, controllers, and clients. You can use Xsan Admin to manage a SAN from any computer that has access to the SAN’s TCP/IP subnet. Xsan Admin is installed in /Applications/Server. Installing Xsan Admin Separately Xsan Admin is included when you install the Xsan software on SAN controller and client computers.
LL2652.
LL2652.book Page 27 Wednesday, July 28, 2004 3:45 PM 3 Setting Up a SAN Volume 3 This chapter contains step-by-step instructions for setting up your first Xsan volumes. Follow the steps in this chapter to set up shared Xsan volumes on a storage area network. Setup Summary You’ll perform the following tasks to set up your first Xsan storage area network. Details for each task are on the indicated pages.
LL2652.book Page 28 Wednesday, July 28, 2004 3:45 PM Setting Up an Xsan Storage Area Network m Step 1: Set Up the Fibre Channel Network Connect controller computers, client computers, and Xserve RAID storage systems to a Fibre Channel network. Be sure to configure the switch and make the connections so that you create a Fibre Channel fabric. For more information, see the guidelines and requirements under “Fibre Channel Fabric” on page 16.
LL2652.book Page 29 Wednesday, July 28, 2004 3:45 PM Step 5: Install Xsan Software on Clients and Controllers Take the Xsan installer disc to each controller and client computer connected to the SAN and install the Xsan software. m To install the Xsan file system and Xsan Admin application: At each computer, insert the disc and double-click the Xsan installer icon. m To install just the file system without Xsan Admin: Click Customize on the final installer window and deselect Xsan Admin.
LL2652.book Page 30 Wednesday, July 28, 2004 3:45 PM Step 7: Set Up Controllers and Clients All computers on the local network with Xsan installed are listed in the Computers pane. Your next step is to choose at least one computer to act as metadata controller and set up the others as clients. 1 Still in the Computers pane, select a computer in the list.
LL2652.book Page 31 Wednesday, July 28, 2004 3:45 PM Step 8: Label and Initialize LUNs (RAID Arrays) Next, prepare (label and initialize) available LUNs for use with the Xsan file system. Each LUN represents a RAID array or slice you set up using RAID Admin. 1 In Xsan Admin, click LUNs on the Setup pane. Responding storage devices are listed by name and size. You should see one LUN for each RAID array or slice you created on Xserve RAID systems attached to the SAN’s Fibre Channel network.
LL2652.book Page 32 Wednesday, July 28, 2004 3:45 PM Step 9: Create Volumes Next, you’ll create the volumes your users will see. 1 In Xsan Admin, click Storage on the Setup pane. 2 Click the New Volume button (next to the empty list). 3 Type a name for the volume. Use only uppercase letters (A-Z), lowercase letters (a-z), and numbers (0-9). Don’t include spaces, underscores (_), or hyphens (-). This is the name users will see in the Finder when the volume is mounted.
LL2652.book Page 33 Wednesday, July 28, 2004 3:45 PM Step 10: Add Storage Pools to the Volumes 1 Select a volume in the list and click the New Storage Pool button (next to the list). 2 In the storage pool dialog, provide the following information. Storage Pool Name: Type a name for the storage pool. If the OK button is disabled after you type a name, the name is reserved. For a list of reserved names, see the Xsan Administrator’s Guide. Use For: Choose the type of data to store in the storage pool.
LL2652.book Page 34 Wednesday, July 28, 2004 3:45 PM Step 12: (Optional) Set Up SAN Status Notifications Xsan can notify you by email or pager when the condition of the SAN changes. If you don’t want to set up notifications now, you can do it later. 1 On the Notification pane, click the Add button (+) next to the list to add a contact. 2 Double-click the new entry, type an email address or the address of a pager textmessaging account, and press Return.
LL2652.book Page 35 Wednesday, July 28, 2004 3:45 PM Step 14: (Optional) Set User and Group Quotas You can set up quotas to control how much space in each SAN volume is used by each user or group. 1 If the volume is not already started, select it in the SAN Components list and click Start Volume. 2 With the volume still selected, click Quotas. 3 Click the Add (+) button, then drag a user or group from the drawer to the quotas list.
LL2652.book Page 36 Wednesday, July 28, 2004 3:45 PM Step 15: Start the Volumes and Mount Them on Clients To make a volume available to a user or application on a client computer, you must use Xsan Admin to start the volume and mount it on the client. Users logged in to client computers can’t browse for or mount SAN volumes themselves. 1 In Xsan Admin, select each new volume in the SAN Components list and click Start Volume. If you set up affinities or quotas on the volume, you have already started it.
Working With StorNext Clients and Controllers Appendix LL2652.book Page 37 Wednesday, July 28, 2004 3:45 PM This chapter describes how to add Macintosh clients to an existing StorNext File System SAN or connect Windows, UNIX, AIX, Irix, or Linux clients to an Xsan SAN.
LL2652.book Page 38 Wednesday, July 28, 2004 3:45 PM Adding Macintosh Clients to a StorNext SAN If you already have a StorNext File System on a storage area network, you can add a Macintosh client using Xsan. To add a Macintosh Xsan client to a StorNext SAN: 1 Connect the Macintosh computer to the SAN’s Ethernet and Fibre Channel networks. 2 Install the Xsan software on the Macintosh computer. 3 License the Xsan software on the Macintosh client.
LL2652.book Page 39 Wednesday, July 28, 2004 3:45 PM Using Xsan Controllers With StorNext Clients You can use ADIC’s StorNext software to access an Xsan SAN from a Windows, UNIX, AIX, Irix, or Linux computer. 1 Connect the non-Macintosh client to the SAN’s Fibre Channel and Ethernet networks. 2 Install the StorNext File System software on the non-Macintosh client following the instructions that ADIC provides in the StorNext package.
LL2652.
Glossary Glossary LL2652.book Page 41 Wednesday, July 28, 2004 3:45 PM affinity An association between a folder on an Xsan volume and one of the storage pools that make up the volume. The affinity guarantees that files placed in the folder are stored only on that storage pool. allocation strategy In Xsan, the order in which data is written to the storage pools that make up a volume. Can be fill, round robin, or balance. balance An Xsan storage pool allocation strategy.
LL2652.book Page 42 Wednesday, July 28, 2004 3:45 PM initialize In general, to prepare a disk for use by a particular file system. In Xsan, to prepare a LUN for use in a storage pool. label (noun) An identifying name for a LUN. label (verb) StorNext File System term for initializing a LUN. See “initialize.” LUN SCSI logical unit number. In Xsan, an unformatted logical storage device such as an Xserve RAID array or slice.
LL2652.book Page 43 Wednesday, July 28, 2004 3:45 PM stripe breadth An Xsan storage pool property. The number of bytes of data, expressed as a number of file system blocks, that Xsan writes to a LUN in a storage pool before moving to the next LUN in the pool. stripe group The StorNext File System term for an Xsan storage pool. volume A mountable allocation of storage that behaves, from the client’s perspective, like a local hard disk, partition, or network volume.
