Data ONTAP 7.3 Storage Management Guide

Data ONTAP 7.3 Storage Management Guide NetApp, Inc. 495 East Java Drive Sunnyvale, CA 94089 USA Telephone: +1 (408) 822-6000 Fax: +1 (408) 822-4501 Support telephone: +1 (888) 4-NETAPP Documentation comments: doccomments@netapp.com Information Web: http://www.netapp.com Part number: 210-04766_A0 Updated for Data ONTAP 7.3.3 on 15 January 2010

Table of Contents 3 Contents Copyright information... 15 Trademark information... 17 About this guide... 19 Audience... 19 Accessing Data ONTAP man pages... 19 Terminology... 20 Where to enter commands... 21 Keyboard and formatting conventions... 22 Special messages... 23 How to send your comments... 23 Data ONTAP storage architecture overview... 25 How Data ONTAP works with disks... 27 What disk types Data ONTAP supports... 27 Disk connection architectures... 28 Fibre Channel Arbitrated Loop (FC-AL) disk connection architecture... 28 Serial attached SCSI (SAS) disk connection architecture... 28 Available disk capacity by disk size... 28 Disk speeds... 30 Disk formats... 30 Disk names... 31 Loop IDs for FC-AL connected disks... 32 RAID disk types... 32 How disk sanitization works... 33 Disk sanitization limitations... 34 What happens if disk sanitization is interrupted... 34 How selective disk sanitization works... 35 Commands to display disk and array LUN information... 35 Commands to display disk space information... 37 How Data ONTAP monitors disk performance and health... 37 When Data ONTAP takes disks offline temporarily... 38 How Data ONTAP reduces disk failures using Rapid RAID Recovery... 38 How the maintenance center works... 39

4 Data ONTAP 7.3 Storage Management Guide How Data ONTAP uses continuous media scrubbing to prevent media errors... 41 How Data ONTAP uses ACP to increase storage availability... 42 Enabling ACP... 42 The ACP subnet... 43 How ownership for disks and array LUNs works... 45 How software-based ownership works... 45 Why you assign ownership of disks and array LUNs... 46 What it means for Data ONTAP to own an array LUN... 46 Why you might assign array LUN ownership after installation... 47 How disks and array LUNs become available for use... 47 How ownership autoassignment works for disks... 49 Examples showing when Data ONTAP can use array LUNs... 50 How hardware-based disk ownership works... 52 Data ONTAP automatically recognizes and assigns disks for hardwarebased disk ownership... 52 How disks are assigned to spare pools when SyncMirror is enabled... 53 Storage system models that support hardware-based ownership or both types... 53 When a storage system uses software-based disk ownership... 54 Managing ownership for disks and array LUNs... 55 Guidelines for assigning ownership for disks... 55 Displaying ownership information... 55 Assigning ownership for disks and array LUNs... 57 Modifying assignment of spare disks or array LUNs... 59 How you use the wildcard character with the disk command... 60 Determining whether a system has hardware-based or software-based disk ownership... 61 Changing between hardware-based and software-based ownership... 61 Changing from hardware-based to software-based disk ownership nondisruptively... 62 Changing from hardware-based to software-based disk ownership using the standard method... 63 Changing from software-based to hardware-based disk ownership for stand-alone systems... 64 About changing from software-based to hardware-based disk ownership for active/active configurations... 65

Table of Contents 5 Reusing disks configured for software-based disk ownership... 65 Automatically erasing disk ownership information... 66 Manually erasing software-based disk ownership information... 66 Recovering from accidental conversion to software-based disk ownership... 67 Managing disks... 69 Adding disks to a storage system... 69 Replacing disks that are currently being used in an aggregate... 70 Converting a data disk to a hot spare... 71 Removing disks from a storage system... 72 Removing a failed disk... 72 Removing a hot spare disk... 73 Removing a data disk... 73 Removing data from disks using disk sanitization... 74 Removing data from disks using selective disk sanitization... 77 Stopping disk sanitization... 82 Managing array LUNs through Data ONTAP... 83 Array LUN name format... 83 Why you might change the checksum type of an array LUN... 84 Changing the checksum type of an array LUN... 85 Prerequisites to reconfiguring a LUN on the storage array... 85 Changing array LUN size or composition... 86 Removing one array LUN from use by Data ONTAP... 87 Removing a storage system using array LUNs from service... 88 Commands to display information about your storage... 89 Commands to display disk and array LUN information... 89 Commands to display disk space information... 90 Commands to display storage subsystem information... 91 Enabling or disabling a host adapter... 95 How Data ONTAP uses RAID to protect your data and data availability... 97 RAID protection levels for disks... 97 What RAID-DP protection is... 98 What RAID4 protection is... 98 RAID protection for third-party storage... 99 Protection provided by RAID and SyncMirror... 99

6 Data ONTAP 7.3 Storage Management Guide RAID disk types... 102 How Data ONTAP RAID groups work... 102 How RAID groups are named... 103 About RAID group size... 103 Considerations for sizing RAID groups for disks... 103 Considerations for Data ONTAP RAID groups for array LUNs... 104 Maximum number of RAID groups... 105 How Data ONTAP works with hot spare disks... 105 How many hot spares you should have... 105 What disks can be used as hot spares... 106 What a matching spare is... 106 What an appropriate hot spare is... 106 About degraded mode... 107 About low spare warnings... 107 How Data ONTAP handles a failed disk with a hot spare... 108 How Data ONTAP handles a failed disk that has no available hot spare... 110 How Data ONTAP handles media errors during reconstruction... 110 How RAID-level disk scrubs verify data integrity... 111 How you schedule automatic RAID-level scrubs... 111 How you run a manual RAID-level scrub... 112 Customizing the size of your RAID groups... 115 Controlling the impact of RAID operations on system performance.. 117 Controlling the performance impact of RAID data reconstruction... 118 Controlling the performance impact of RAID-level scrubbing... 118 Controlling the performance impact of plex resynchronization... 119 Controlling the performance impact of mirror verification... 120 How aggregates work... 123 How unmirrored aggregates work... 124 How mirrored aggregates work... 125 Aggregate states and status... 127 How you can use disks with mixed speeds in the same aggregate... 128 How to control disk selection from heterogeneous storage... 129 Rules for mixing disk types in aggregates... 130 Rules for mixing array LUNs in an aggregate... 131 Checksum rules for adding storage to an aggregate... 132 What happens when you add larger disks to an aggregate... 132

Table of Contents 7 Managing aggregates... 135 Creating an aggregate... 135 Increasing the size of an aggregate... 138 What happens when you add storage to an aggregate... 140 Forcibly adding disks to aggregates... 140 Taking an aggregate offline... 141 Bringing an aggregate online... 141 Putting an aggregate into restricted state... 142 Changing the RAID level of an aggregate... 143 Changing an aggregate's RAID level from RAID4 to RAID-DP... 143 Changing an aggregate's RAID level from RAID-DP to RAID4... 144 Determining how the space in an aggregate is being used... 145 Destroying an aggregate... 146 Undestroying an aggregate... 147 Physically moving an aggregate composed of disks... 147 Moving an aggregate composed of array LUNs... 149 How volumes work... 153 How FlexVol volumes work... 153 How traditional volumes work... 154 Attributes you can set for volumes... 154 How volumes use the language attribute... 155 How file access protocols affect what language to use for your volumes... 155 How you manage duplicate volume names... 156 Volume states and status... 156 About the CIFS oplocks setting... 159 How security styles affect access to your data... 159 How UNIX permissions are affected when files are edited using Windows applications... 161 What the default security style is for new volumes and qtrees... 161 How Data ONTAP can automatically provide more free space for full volumes... 162 About the maximum number of files allowed on a volume... 162 The root volume... 163 Recommendations regarding the root volume... 163 Size requirement for root FlexVol volumes... 164 General volume operations... 167 Migrating from traditional volumes to FlexVol volumes... 167

8 Data ONTAP 7.3 Storage Management Guide Preparing your destination volume... 168 Migrating your data... 170 Completing your migration... 170 Putting a volume into restricted state... 172 Taking a volume offline... 172 Bringing a volume online... 173 Renaming a volume... 173 Destroying a volume... 174 Changing the maximum number of files allowed in a volume... 175 Changing the language for a volume... 175 Changing the root volume... 176 FlexVol volume operations... 179 Creating a FlexVol volume... 179 Resizing a FlexVol volume... 181 Configuring a FlexVol volume to grow automatically... 182 Configuring automatic free space preservation for a FlexVol volume... 182 Displaying a FlexVol volume's containing aggregate... 183 Traditional volume operations... 185 Creating a traditional volume... 185 About FlexCache volumes... 189 FlexCache hardware and software requirements... 190 Limitations of FlexCache volumes... 191 Types of volumes you can use for FlexCache... 192 How the FlexCache Autogrow capability works... 192 How FlexCache volumes use space management... 193 How FlexCache volumes share space with other volumes... 193 How you display FlexCache statistics... 194 What happens when connectivity to the origin system is lost... 194 How the NFS export status of the origin volume affects FlexCache access... 197 How FlexCache caching works... 197 Files are the basic caching unit... 197 How cache consistency is achieved... 198 Cache hits and misses... 200 Typical FlexCache deployments... 201 WAN deployment... 201 LAN deployment... 201

Table of Contents 9 About using LUNs in FlexCache volumes... 202 What FlexCache status messages mean... 202 How FlexCache volumes connect to their origin volume... 203 About SA systems... 203 FlexCache volume operations... 205 Creating FlexCache volumes... 205 Displaying free space for FlexCache volumes... 206 Configuring the FlexCache Autogrow capability... 206 Flushing files from FlexCache volumes... 207 Displaying FlexCache client statistics... 207 Displaying FlexCache server statistics... 208 Displaying FlexCache status... 208 About FlexClone volumes... 209 How FlexClone volumes work... 209 Operations not supported on FlexClone volumes or their parents... 210 FlexClone volumes and space guarantees... 211 FlexClone volumes and shared Snapshot copies... 212 How you can identify shared Snapshot copies in FlexClone volumes... 212 How you use volume SnapMirror replication with FlexClone volumes... 212 About creating a volume SnapMirror relationship using an existing FlexClone volume or its parent... 213 About creating a FlexClone volume from volumes currently in a SnapMirror relationship... 213 How splitting a FlexClone volume from its parent works... 213 FlexClone volumes and LUNs... 214 FlexClone volume operations... 215 Creating a FlexClone volume... 215 Splitting a FlexClone volume from its parent... 216 Determining the parent volume and base Snapshot copy for a FlexClone volume. 217 Determining the space used by a FlexClone volume... 217 About FlexClone files and FlexClone LUNs... 219 How FlexClone files and FlexClone LUNs work... 219 Collective usage of FlexClone at file, LUN, and volume level... 221 Uses of FlexClone files and FlexClone LUNs... 223 Considerations when planning FlexClone files or FlexClone LUNs... 223 Differences between FlexClone LUNs and LUN clones... 224

10 Data ONTAP 7.3 Storage Management Guide Operational limits for FlexClone files and FlexClone LUNs... 225 What happens when clients write new data to parent or FlexClone files and FlexClone LUNs... 228 What happens when FlexClone files, FlexClone LUNs, or parents are deleted... 228 Space savings achieved by using FlexClone files and FlexClone LUNs... 229 What the FlexClone log file is... 229 Rapid Cloning Utility for VMware... 230 FlexClone file and FlexClone LUN interoperability with Data ONTAP features.. 231 How Snapshot copies work with FlexClone files and FlexClone LUNs... 231 How volume SnapMirror works with FlexClone files and FlexClone LUNs... 232 How synchronous SnapMirror works with FlexClone files and FlexClone LUNs... 233 How qtree SnapMirror and SnapVault work with FlexClone files and FlexClone LUNs... 233 How deduplication works with FlexClone files and FlexClone LUNs... 233 How quotas work with FlexClone files and FlexClone LUNs... 234 How space reservation works with FlexClone files and FlexClone LUNs. 234 How MultiStore works with FlexClone files and FlexClone LUNs... 234 How NDMP and dump works with FlexClone files and FlexClone LUNs... 236 How single file SnapRestore works with FlexClone files and FlexClone LUNs... 236 How file folding works with FlexClone files and FlexClone LUNs... 236 How volume SnapRestore works with FlexClone files and FlexClone LUNs... 236 How volume autosize works with FlexClone files and FlexClone LUNs... 237 How volume-copy works with FlexClone files and FlexClone LUNs... 237 How volume clone works with FlexClone files and FlexClone LUNs... 237 How FlexClone files and FlexClone LUNs work when the system reboots... 238 How an active/active configuration works with FlexClone files and FlexClone LUNs... 238 How role-based access control lists work with FlexClone files and FlexClone LUNs... 238

Table of Contents 11 How access control lists and streams work with FlexClone files and FlexClone LUNs... 238 How FlexShare works with FlexClone files and FlexClone LUNs... 239 FlexClone file and FlexClone LUN operations... 241 Creating a FlexClone file or FlexClone LUN... 242 Viewing the status of a FlexClone file or FlexClone LUN operation... 244 Stopping a FlexClone file or FlexClone LUN operation... 245 Clearing the status of a failed FlexClone file or FlexClone LUN operation... 246 Viewing the space savings due to FlexClone files and FlexClone LUNs... 246 Considerations when creating FlexClone files or FlexClone LUNs... 247 What happens when FlexClone file or LUN operation fails... 247 When a FlexClone file or LUN is moved or renamed during cloning operation... 248 Space savings with deduplication... 249 How deduplication works... 250 What deduplication metadata is... 250 Activating the deduplication license... 251 Guidelines for using deduplication... 251 Maximum volume size for different systems... 252 Performance considerations for deduplication... 253 Deduplication and read reallocation... 254 Deduplication and extents... 254 Deduplication schedules... 254 Default schedule for deduplication... 255 Creating a deduplication schedule... 255 Running deduplication manually on existing data... 256 When deduplication runs automatically... 256 Deduplication operations... 257 How deduplication works with other features and products... 262 Deduplication and Snapshot copies... 262 Deduplication and volume SnapMirror... 263 Deduplication and qtree SnapMirror... 264 Deduplication and SnapVault... 265 Deduplication and synchronous SnapMirror... 266 Deduplication and tape backups... 266 Deduplication and SnapRestore... 267

12 Data ONTAP 7.3 Storage Management Guide Deduplication and SnapLock volumes... 267 Deduplication and MetroCluster... 267 Deduplication and DataFabric Manager 3.8... 267 Deduplication and volume copy... 268 Deduplication and FlexClone volumes... 269 Deduplication and an active/active configuration... 269 Deduplication and VMware... 270 Deduplication and MultiStore... 271 Common troubleshooting procedures for volumes with deduplication... 273 How space management works... 275 What kind of space management to use... 275 What space guarantees are... 277 What kind of space guarantee traditional volumes provide... 278 How you set space guarantees for new or existing volumes... 278 What space reservation is... 278 How Data ONTAP can automatically provide more free space for full volumes... 278 How aggregate overcommitment works... 279 Considerations for bringing a volume online in an overcommited aggregate... 280 About qtrees... 281 When you use qtrees... 281 How qtrees compare with volumes... 281 Qtree name restrictions... 282 Managing qtrees... 283 Creating a qtree... 283 Displaying qtree status... 284 Displaying qtree access statistics... 284 Converting a directory to a qtree... 285 Converting a directory to a qtree using a Windows client... 286 Converting a directory to a qtree using a UNIX client... 286 Deleting a qtree... 287 Renaming a qtree... 288 Managing CIFS oplocks... 289 About the CIFS oplocks setting... 289 Enabling or disabling CIFS oplocks for the entire storage system... 290 Enabling CIFS oplocks for a specific volume or qtree... 290

Table of Contents 13 Disabling CIFS oplocks for a specific volume or qtree... 290 Changing security styles... 293 About quotas... 295 Why you use quotas... 295 Overview of the quota process... 296 About quota notifications... 296 Quota targets and types... 297 Special kinds of quotas... 298 How default quotas work... 298 How you use explicit quotas... 299 How derived quotas work... 299 How you use tracking quotas... 300 How quotas work with users and groups... 301 How you specify UNIX users for quotas... 301 How you specify Windows users for quotas... 302 How quotas are applied to the root user... 303 How quotas work with special Windows groups... 304 How quotas are applied to users with multiple IDs... 304 How Data ONTAP determines user IDs in a mixed environment... 305 How quotas with multiple users work... 305 How you link UNIX and Windows names for quotas... 306 How quotas work with qtrees... 308 How tree quotas work... 308 How user and group quotas work with qtrees... 308 When quotas are not inherited from volumes by qtrees... 309 Differences among hard, soft, and threshold quotas... 309 How the quotas file works... 309 The syntax of quota entries... 310 How Data ONTAP reads the quotas file... 314 What character encodings are supported by the quotas file... 315 Sample quotas file... 315 About activating or reinitializing quotas... 316 About modifying quotas... 317 When you can use resizing... 317 When a full quota reinitialization is required... 319 How qtree changes affect quotas... 319

14 Data ONTAP 7.3 Storage Management Guide How deleting a qtree affects tree quotas... 320 How renaming a qtree affects quotas... 320 How changing the security style of a qtree affects user quotas... 320 How quotas work with vfiler units... 321 How quota reports work... 321 What fields quota reports contain... 321 How quota report options affect quota reports... 322 How the ID field is displayed in quota reports... 323 Progressive quota examples... 324 Managing quotas... 329 Activating quotas... 329 Reinitializing quotas... 330 Deactivating quotas... 331 Canceling quota initialization... 331 Resizing quotas... 332 Deleting quotas... 332 Deleting a quota by removing resource restrictions... 332 Deleting a quota by removing the quotas file entry... 333 Managing quota message logging... 333 Displaying a quota report... 334 Storage limits... 335 Abbreviations... 341 Index... 357

Copyright information 15 Copyright information Copyright 1994 2010 NetApp, Inc. All rights reserved. Printed in the U.S.A. No part of this document covered by copyright may be reproduced in any form or by any means graphic, electronic, or mechanical, including photocopying, recording, taping, or storage in an electronic retrieval system without prior written permission of the copyright owner. Software derived from copyrighted NetApp material is subject to the following license and disclaimer: THIS SOFTWARE IS PROVIDED BY NETAPP "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL NETAPP BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. NetApp reserves the right to change any products described herein at any time, and without notice. NetApp assumes no responsibility or liability arising from the use of products described herein, except as expressly agreed to in writing by NetApp. The use or purchase of this product does not convey a license under any patent rights, trademark rights, or any other intellectual property rights of NetApp. The product described in this manual may be protected by one or more U.S.A. patents, foreign patents, or pending applications. RESTRICTED RIGHTS LEGEND: Use, duplication, or disclosure by the government is subject to restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.277-7103 (October 1988) and FAR 52-227-19 (June 1987).

Trademark information 17 Trademark information All applicable trademark attribution is listed here. NetApp, the Network Appliance logo, the bolt design, NetApp-the Network Appliance Company, Cryptainer, Cryptoshred, DataFabric, DataFort, Data ONTAP, Decru, FAServer, FilerView, FlexClone, FlexVol, Manage ONTAP, MultiStore, NearStore, NetCache, NOW NetApp on the Web, SANscreen, SecureShare, SnapDrive, SnapLock, SnapManager, SnapMirror, SnapMover, SnapRestore, SnapValidator, SnapVault, Spinnaker Networks, SpinCluster, SpinFS, SpinHA, SpinMove, SpinServer, StoreVault, SyncMirror, Topio, VFM, and WAFL are registered trademarks of NetApp, Inc. in the U.S.A. and/or other countries. gfiler, Network Appliance, SnapCopy, Snapshot, and The evolution of storage are trademarks of NetApp, Inc. in the U.S.A. and/or other countries and registered trademarks in some other countries. The NetApp arch logo; the StoreVault logo; ApplianceWatch; BareMetal; Camera-to-Viewer; ComplianceClock; ComplianceJournal; ContentDirector; ContentFabric; Data Motion; EdgeFiler; FlexShare; FPolicy; Go Further, Faster; HyperSAN; InfoFabric; Lifetime Key Management, LockVault; NOW; ONTAPI; OpenKey, RAID- DP; ReplicatorX; RoboCache; RoboFiler; SecureAdmin; SecureView; Serving Data by Design; Shadow Tape; SharedStorage; Simplicore; Simulate ONTAP; Smart SAN; SnapCache; SnapDirector; SnapFilter; SnapMigrator; SnapSuite; SohoFiler; SpinMirror; SpinRestore; SpinShot; SpinStor; vfiler; VFM Virtual File Manager; VPolicy; and Web Filer are trademarks of NetApp, Inc. in the U.S.A. and other countries. NetApp Availability Assurance and NetApp ProTech Expert are service marks of NetApp, Inc. in the U.S.A. IBM, the IBM logo, and ibm.com are trademarks or registered trademarks of International Business Machines Corporation in the United States, other countries, or both. A complete and current list of other IBM trademarks is available on the Web at http://www.ibm.com/legal/copytrade.shtml. Apple is a registered trademark and QuickTime is a trademark of Apple, Inc. in the U.S.A. and/or other countries. Microsoft is a registered trademark and Windows Media is a trademark of Microsoft Corporation in the U.S.A. and/or other countries. RealAudio, RealNetworks, RealPlayer, RealSystem, RealText, and RealVideo are registered trademarks and RealMedia, RealProxy, and SureStream are trademarks of RealNetworks, Inc. in the U.S.A. and/or other countries. All other brands or products are trademarks or registered trademarks of their respective holders and should be treated as such. NetApp, Inc. is a licensee of the CompactFlash and CF Logo trademarks. NetCache is certified RealSystem compatible.

About this guide 19 About this guide You can use your product more effectively when you understand this document's intended audience and the conventions that this document uses to present information. This document describes how to configure, operate, and manage the storage resources for storage systems that run Data ONTAP software. It covers disks, RAID groups, plexes, and aggregates, and how file systems, or volumes, and qtrees are used to organize and manage data. Next topics Audience on page 19 Accessing Data ONTAP man pages on page 19 Terminology on page 20 Where to enter commands on page 21 Keyboard and formatting conventions on page 22 Special messages on page 23 How to send your comments on page 23 Audience This document is written with certain assumptions about your technical knowledge and experience. This document is for system administrators and service personnel who are familiar with storage system equipment and who need to perform the following tasks: Create and maintain aggregates and volumes Remove and replace disks Organize or limit access to storage space using qtrees and quotas Accessing Data ONTAP man pages You can use the Data ONTAP manual (man) pages to access technical information. About this task Data ONTAP manual pages are available for the following types of information. They are grouped into sections according to standard UNIX naming conventions.

20 Data ONTAP 7.3 Storage Management Guide Types of information Man page section Commands 1 Special files 4 File formats and conventions 5 System management and services 8 Step 1. View man pages in the following ways: Enter the following command at the storage system command line: man command_or_file_name Click the manual pages button on the main Data ONTAP navigational page in the FilerView user interface. Use the Commands: Manual Page Reference, Volumes 1 and 2 (which can be downloaded or ordered through the NOW site). Note: All Data ONTAP man pages are stored on the storage system in files whose names are prefixed with the string "na_" to distinguish them from client man pages. The prefixed names are used to distinguish storage system man pages from other man pages and sometimes appear in the NAME field of the man page, but the prefixes are not part of the command, file, or services. Terminology To understand the concepts in this document, you might need to know how certain terms are used. Storage terms array LUN LUN (logical unit number) native disk native disk shelf Refers to storage that third-party storage arrays provide to storage systems running Data ONTAP software. One array LUN is the equivalent of one disk on a native disk shelf. Refers to a logical unit of storage identified by a number. Refers to a disk that is sold as local storage for storage systems that run Data ONTAP software. Refers to a disk shelf that is sold as local storage for storage systems that run Data ONTAP software.

About this guide 21 storage controller storage system third-party storage Refers to the component of a storage system that runs the Data ONTAP operating system and controls its disk subsystem. Storage controllers are also sometimes called controllers, storage appliances, appliances, storage engines, heads, CPU modules, or controller modules. Refers to the hardware device running Data ONTAP that receives data from and sends data to native disk shelves, third-party storage, or both. Storage systems that run Data ONTAP are sometimes referred to as filers, appliances, storage appliances, V-Series systems, or systems. Refers to the back-end storage arrays, such as IBM, Hitachi Data Systems, and HP, that provide storage for storage systems running Data ONTAP. Cluster and high-availability terms active/active configuration cluster In the Data ONTAP 7.2 and 7.3 release families, refers to a pair of storage systems (sometimes called nodes) configured to serve data for each other if one of the two systems stops functioning. Also sometimes referred to as active/active pairs. In the Data ONTAP 7.1 release family and earlier releases, this functionality is referred to as a cluster. In the Data ONTAP 7.1 release family and earlier releases, refers to a pair of storage systems (sometimes called nodes) configured to serve data for each other if one of the two systems stops functioning. In the Data ONTAP 7.3 and 7.2 release families, this functionality is referred to as an active/active configuration. Where to enter commands You can use your product more effectively when you understand how this document uses command conventions to present information. You can perform common administrator tasks in one or more of the following ways: You can enter commands either at the system console or from any client computer that can obtain access to the storage system using a Telnet or Secure Shell (SSH) session. In examples that illustrate command execution, the command syntax and output shown might differ from what you enter or see displayed, depending on your version of the operating system. You can use the FilerView graphical user interface. For information about accessing your system with FilerView, see the Data ONTAP System Administration Guide. You can enter Windows, ESX, HP-UX, AIX, Linux, and Solaris commands at the applicable client console. In examples that illustrate command execution, the command syntax and output shown might differ from what you enter or see displayed, depending on your version of the operating system.

22 Data ONTAP 7.3 Storage Management Guide Keyboard and formatting conventions You can use your product more effectively when you understand how this document uses keyboard and formatting conventions to present information. Keyboard conventions Convention What it means The NOW site Refers to NetApp On the Web at http://now.netapp.com/. Enter, enter Used to refer to the key that generates a carriage return; the key is named Return on some keyboards. Used to mean pressing one or more keys on the keyboard and then pressing the Enter key, or clicking in a field in a graphical interface and then typing information into the field. hyphen (-) type Used to separate individual keys. For example, Ctrl-D means holding down the Ctrl key while pressing the D key. Used to mean pressing one or more keys on the keyboard. Formatting conventions Convention What it means Italic font Words or characters that require special attention. Placeholders for information that you must supply. For example, if the guide says to enter the arp -d hostname command, you enter the characters "arp -d" followed by the actual name of the host. Book titles in cross-references. Monospaced font Command names, option names, keywords, and daemon names. Information displayed on the system console or other computer monitors. Contents of files. File, path, and directory names. Bold monospaced font Words or characters you type. What you type is always shown in lowercase letters, unless your program is case-sensitive and uppercase letters are necessary for it to work properly.