Hp Storage Mirroring V5.1 Software Manuale Utente

User’s GuideTwelfth Edition (March 2009)Part Number: T2558-96325

1 - 3Storage Mirroring operationsStorage Mirroring performs four basic types of operations.  Mirroring—The initial copy or subsequent resynchronizati

15 - 1ArchivingStorage Mirroring Archiving Option is an add-on feature of Storage Mirroring that allows you to archive files on your source. By archiv

15 - 2Important archiving requirements and informationReview the following requirements and caveats before using the archiving functionality.  To acc

15 - 3 You must configure you anti-virus software so that the Storage Mirroring application is a low-risk process. Configure the low-risk processes s

15 - 4Archiving security configurationBefore you can use Storage Mirroring Archiving Option, you must establish a specific security configuration. Thi

15 - 5Archiving reportTo help you plan archiving and fine-tune your archive settings, you can generate a preview report. The archiving preview report

15 - 6Manual archivingArchiving can be performed manually anytime after an initial mirror and when another mirror is not in progress. You can archive

15 - 7Scheduled archivingArchiving can be scheduled to occur automatically at periodic intervals. 1. Right-click the connection on the right pane of t

15 - 8Archive optionsYou have one archiving option available, and you can also validate the recall process. 1. Right-click the connection on the right

15 - 9Recalling files from the targetWhen a file has been archived, the link file is still accessible on the source. The link file has an offline file

16 - 1Restoration for Disaster RecoveryIf you are not using failover and your connection is for disaster recovery, the Management Console provides an

1 - 4ReplicationReplication is the real-time transmission of file changes. Unlike other related technologies, which are based on a disk driver or a sp

16 - 27. Select the Use Backup Replication Set check box to use the target’s copy of the replication set database for the restoration. If this check b

16 - 312. If you selected the link restore, specify where you want the archive data to be located. Specify One Per Volume to use one archive bin on ea

17 - 1Failover for High AvailabilityFailover is the process in which a target stands in for a failed source. As a result, user and application request

17 - 2Configuration requirementsStorage Mirroring failover can be implemented with very little configuration necessary in small or simple networks, bu

17 - 3Cluster configurationsIf your target is a cluster, you will need to create two failover scripts. 1. On the target cluster, select Start, Program

17 - 4 Target’s Primary WINS server—116.123.2.50 First secondary WINS server on the network—192.168.1.110 Second secondary WINS server on the netwo

17 - 5DNSWhen Storage Mirroring failover occurs, DNS is not automatically updated. If the end-users use DNS to resolve server names and the source IP

17 - 6 Full qualified domain name of the source—Alpha.domain.com Source IP address—192.168.1.108 Fully qualified domain name of the target—Beta.dom

17 - 7k. Restart the Windows Management Instrumentation service for the changes to take effect. .4. Add the same user account that has full control on

17 - 8Options  SETPASSWORD user_name password—Stores user credentials in an encrypted file for later use. This option must be run separately from a

1 - 5Failure monitoring and failoverFailover is the process in which a target stands in for a failed source. As a result, user and application request

17 - 9Macintosh sharesA share is any volume, drive, or directory resource that is shared across a network. During failover, the target can assume or a

17 - 10NFS sharesA share is any volume, drive, or directory resource that is shared across a network. During failover, the target can assume or add an

17 - 11Configuring failover1. The Failover Control Center can be started from within the Management Console or from the Windows desktop. From the Man

17 - 12Repeat this step for each IP address that is being monitored. 9. Highlight an IP address that you have selected for monitoring and select a

17 - 1311. If you are monitoring multiple IP addresses, highlight the source name and specify the Failover Trigger. All Monitored IP Addresses Fail—F

17 - 14 Server Name—Failover is performed on the server name. If you specify the server name to be failed over, first Storage Mirroring checks the ho

17 - 15 If you want to pass any arguments to your script, specify the arguments.  If you want to delay the failover or failback processes until the

17 - 16Editing failover configurationIf you want to edit the monitor settings for a source that is currently being monitored, highlight that source on

17 - 17The following table identifies how the visual indicators change as the status of failover changes. Updating shares manuallyShare inform

17 - 18Failover manual interventionIf Manual Intervention is enabled, the Failover Control Center will prompt you when a failure occurs. Click Cancel

1 - 6RestorationRestoration provides an easy method for copying replicated data from the target back to its original location on the source. The proc

18 - 1Restoration and Failback for High AvailabilityWith a high availability connection, failover occurred because the target was monitoring the sourc

18 - 2 Your target is standing in for your source because of failover, and users are accessing their data from the target.  Your source is back onli

18 - 3f. The Restore To and Restore From paths will automatically be populated when the replication set is selected. The restore to path is the direct

18 - 4c. When failback is complete, the post-failback script, if configured, will be started. When the script is complete, you will be prompted to det

18 - 5Failback then restorationFailback before restoration can be a simpler process, but it may require additional downtime. The amount of downtime wi

18 - 67. Now you can begin your restoration process. a. From the Management Console on the target, select Tools, Restoration Manager. b. Identify t

18 - 7 Only if backup copy is more recent—This option restores only those files that are newer on the target than on the source. The entire file is o

19 - 1Monitoring ToolsIn addition to the monitoring capabilities within the Storage Mirroring clients, you can monitor Storage Mirroring processing us

19 - 2Log filesVarious Storage Mirroring components (Storage Mirroring service, Management Console, Failover Control Center, and the Command Line Clie

19 - 3Viewing the log filesThe log files can be viewed, from the location where Storage Mirroring is installed, with a standard text viewer. Sample S

1 - 7Sample configurationsStorage Mirroring is an exceptionally flexible product that can be used in a wide variety of network configurations. To impl

19 - 4Using LogViewerLog file output can be filtered using the Storage Mirroring LogViewer utility. Use the LogViewer command from the directory where

19 - 5Log messagesThe following table describes some of the standard Storage Mirroring alerts that may be displayed in the log files. The ID appears i

19 - 678 Auto-disconnect threshold has been reached. The Storage Mirroring queue has exceeded its limit, and the auto-disconnect process will disconne

19 - 795 Verification ended con_id The verification process of confirming that the Storage Mirroring data on the target is identical to the data on

19 - 852000 Unfinished Op error This error message contains various Microsoft API codes. The text Code -<x> Internal <y> appears at the en

19 - 9600002  Unified login provides ADMIN access User user has level access (x) Using the current login grants ADMIN access. The listed user has

19 - 10Windows Event ViewerIn the Windows operating system, an event is a significant occurrence in the system or in an application that requires admi

19 - 111000 DTCounters Error An exception occurred: %1 Run the installation and select Repair. Contact technical support if this event occurs again. 1

19 - 124008 Service Info. Auto-disconnect has succeeded for %1 (%2) for Replication Set %3, ID: %4No action required. 4009 Service Info. Auto-reconnec

19 - 134027 Service Info. The target has been resumed due to user intervention.No action required. 4028 Service Warning Registration of service class

1 - 8One-to-one, active/active Description Each server acts as both a source and target actively replicating data to each other. Applic

19 - 144038 Service Error Error verifying the product code. The product functionality has been disabled.Reinstall the software, using the installation

19 - 154050 Service Info. Service has resumed a delete orphans task to %1 (%2) for Replication Set %3, ID: %4No action required. 4051 Service Info. Se

19 - 164067 Service Error No replication ops have been received from the driver for an extended period of time.Check other messages for errors with th

19 - 174100 System Error The versions of the driver and the filter driver do not match. Replication will not occur. Reboot your server. If this error

19 - 184201 Service Warning In band task %1 discarded (submitted from %2 by %3 at %4)A task may be discarded in the following scenarios: all connectio

19 - 194400 Service Error Failed to create snapshot set for source %1 (%2) Connection ID: %3. Error: %4The snapshot could not created. This may be due

19 - 205001 Service Info. Server Monitor service was successfully stopped.No action required.5002 Service Info. Placeholders were modified to %1.No ac

19 - 215304 Monitoring Info The application monitor script has finished successfully. No action required. 5305 Monitoring Warning The application mon

19 - 225506 Service Warning One or more required e-mail settings have not been specified (error code: %1).At a minimum, you must specify the e-mail se

19 - 238198 Resources Warning The driver registry path could not be saved. The default registry path will be used. No action required. 8200 Resources

1 - 9Many-to-one Description Many source servers are protected by one target server.Application This configuration is appropriate fo

19 - 249105 RepKap Error The driver encountered an error querying for file security from the service input buffer. Check the Event Viewer Application

19 - 259112 RepKap Error The driver encountered an error writing a directory query to the service input buffer. Check the Event Viewer Application log

19 - 269120 RepKap Error The driver encountered an error querying for file information from the service input buffer. Check the Event Viewer Applicati

19 - 2710102 RepKap Error The driver could not recall the file. The last Word in the Data window is the exception code.11000 Service Info. Service ha

19 - 2812005 DTRecall Error Service encountered SetServiceStatus error (Error %1) Restart the Storage Mirroring Archiving Option service. Reinstall th

19 - 29DTStatStatistics logging is the process of taking snapshots of Storage Mirroring statistical data. The data can be written to a file for future

19 - 30Configuring the statistics file1. Right-click a machine in the left pane of the Management Console and select Properties. 2. Select the Loggi

19 - 31Running DTStat from the command promptFrom a command prompt, use the DTStat command from the location where Storage Mirroring is installed.

19 - 32DTStat statisticsThe following statistics appear in the default statistic.sts file. NOTE: The categories you see will dep

19 - 33Kernel MirOpsGenerated The number of mirror operations transmitted to the target. Mirroring is completed by transmitting the file system opera

1 - 10One-to-many Description One source server sends data to multiple target servers. The target servers may or may not be accessibl

19 - 34Target Bytes In Target Disk Queue The number of bytes currently in the disk queue on the targetTasksSucceeded The number of task commands that

19 - 35Connection conOpsInMirQueue The number of mirror operations currently waiting to be executed on the targetconBytesInRepQueue The number of rep

19 - 36Windows Performance MonitorPerformance Monitor is a graphical tool for measuring the performance. It provides charting, alerting, and reporting

19 - 37Connection Tasks succeeded The number of task commands that have succeeded on the sourceKernel Activation code failures The number of activ

19 - 38Target aOrphan Bytes The number of orphan bytes removed from the targetOrphan Directories The number of orphan directories removed from the t

19 - 39SNMPSNMP, Simple Network Management Protocol, is the Internet's standard for remote monitoring and management of hosts, routers and other

19 - 40General dtAutoDisCount The number of auto-disconnectsdtAutoReCount The number of auto-reconnectsdtDriverQueuePercent The amount of throttlin

19 - 41SNMP trapsThe following tables identify the Storage Mirroring traps provided through SNMP. Connection dtconOpsInMirQueue The number of mirror

19 - 42Connection dttrapConnectionPause The source to target connection has pauseddttrapConnectionResume The source to target connection has resumedd

19 - 43Restoration dttrapRestoreStarted Restoration has starteddttrapRestoreComplete Restoration is completeReplication Sets dttrapRepSetModified Rep

1 - 11Chained Description The source servers sends replicated data to a target server, which acts as a source server and sends data to a

20 - 1Server SettingsMost of the Storage Mirroring server settings are located in the Management Console Server Properties dialog box. To access this

20 - 2GeneralThe General tab identifies the server.  Nickname—A nickname is saved in the Management Console workspace, therefore, it only

20 - 3LicensingThe Licensing tab identifies the Storage Mirroring license(s) applied to the server. The display for this tab will vary depending on di

20 - 4SetupThe Setup tab contains various setup options.  Log Statistics Automatically—If enabled, Storage Mirroring statistics logging will s

20 - 5 Full—All files are sent to the target.  Server Shutdown Timeout—This setting indicates the amount of time, in seconds, for the service to wa

20 - 6QueueThe Queue tab contains settings for Storage Mirroring queue usage.  Folder—This is the location where the disk q

20 - 7 Maximum system memory for queue—This is the amount of Windows system memory, in MB, that will be used to store data in queues. When exceeded,

20 - 8SourceThe Source tab contains settings specific to the source module of Storage Mirroring.  Replication Packets to 1 Mirror Packet—You can s

20 - 9will vary depending on the type of file activity and other variables. For instance, it will not affect the overall performance of large database

20 - 10TargetThe Target tab contains settings specific to the target module of Storage Mirroring.  Target Mirror Capacity High Perc

1 - 12Single server Description Source and target Storage Mirroring components are loaded on the same server allowing data to be replicat

20 - 11 Remove after the following number of days—If you are moving deleted files, you can specify a length of time, in days, to maintain the moved f

20 - 12DatabaseThe Database tab identifies the Storage Mirroring database files.  Folder—Specify the directory where each of the data

20 - 13LoggingThe Logging tab contains settings for various Storage Mirroring log files.  Folder—Specify the directory where each of

20 - 14 Write Interval—Specify how often Storage Mirroring writes to the statistics log file. The default is every 5 minutes.  Archive Preview  Fil

20 - 15E-mail notificationThe E-mail Notification tab allows you to specify e-mail notification settings. When enabled, the messages logged to the Win

20 - 16If desired, enable Add event description to subject to have the description of the Event Viewer message appended to the end of the subject line

21 - 1Error CodesYou may see error codes used in the user interfaces, log files, or in response to DTCL commands, This chapter contains a complte list

21 - 2-131 No Storage Mirroring target identified-132 Memory is low -133 Memory is sufficient-134 Replication is pending -135 Invalid option supplied-

21 - 3-166 Target is no longer retrying operations-167 Restore required state is unknown-168 Not a valid failover source -169 Failover login failed-17

21 - 4-212 Failback is in progress-213 IP address placeholders on the target are unavailable -214 Target NIC was not found-215 Source module is not lo

© Copyright 2009 Hewlett-Packard Development Company, L.P.Hewlett-Packard Company makes no warranty of any kind with regard to this material, includin

1 - 13Virtual systems Description Source and/or target Storage Mirroring components are loaded on the guest operating system allowing dat

21 - 5-2302 Bandwidth limiting name exists-2303 Bandwidth limit not found-2304 Bandwidth limit day is invalid-2305 Bandwidth limit lable is invalid-24

22 - 1SecurityTo ensure protection of your data, Storage Mirroring offers multi-level security using native operating system security features. Privil

22 - 2How Storage Mirroring security works1. When any Storage Mirroring client machine attempts to access a source or target machine running on Window

22 - 3Clearing maintained security credentialsTo remove cached credentials, follow these steps. 1. To access the credentials security option, select F

22 - 4Storage Mirroring serviceBy default, Storage Mirroring is configured to log on as the system account. If you want to select a specific account t

22 - 5Storage Mirroring groupsStorage Mirroring requires two local groups on each source and target for security. During the installation process, the

22 - 6Windows Active DirectoryActive Directory, a central component of Windows, manages information about the resources in a networking environment. A

IIndexAactivation code 20-3Active Directory 22-6add-ons 20-3alternate data streams 4-3archiving 15-1Bbandwidth limitations 13-5block target paths 10-1

IIOone-to-many configuration 1-10one-to-one configuration 1-7, 1-8orphan files 11-6overviewoperations 1-3product 1-1PPerformance Monitor 19-36portsFai

1 - 14ResourcesYou have many resources available to you when using Storage Mirroring.  Operating System and application documentation—Make sure th

2 - 1InstallationReview System requirements on page 2-1 and Installation and upgrade notes on page 2-3, and then use the appropriate instructions from

2 - 2 File System—Storage Mirroring supports the same file system formats that Microsoft supports: FAT, FAT32, and NTFS.  System Memory—There

2 - 3Installation and upgrade notes Since Storage Mirroring installs device drivers, it is recommended that you update your Windows Recovery Disk, be

2 - 4Installing or upgrading Storage MirroringUse these instructions to install Storage Mirroring or upgrade an existing Storage Mirroring installatio

2 - 5 If you have entered an evaluation activation code, the expiration date will be displayed and you will be prompted that the source and target mo

2 - 6Installing or upgrading Storage Mirroring automaticallyThe Storage Mirroring installation program can accept command-line parameters which allow

2 - 7Review the following table to understand the different parameters available in DTSetup.ini. DTSetup.ini Paramters If you are performing a local

2 - 87. Run one of the following case-sensitive commands from the temporary directory, depending on if you have setup.exe or setup_xxxx.exe where xxxx

iTable of ContentsChapter 1 Introduction ...1-1Storage Mirroring operations ...

2 - 9Uninstalling Storage MirroringUse these instructions if you want to uninstall an existing Storage Mirroring installation. If you want to use the

2 - 10Uninstalling Storage Mirroring automaticallyLike the Storage Mirroring installation program, you can automate the uninstall of Storage Mirroring

3 - 1ClientsStorage Mirroring has two clients, the Management Console and the Failover Control Center that control and manage your connections and fai

3 - 2Logging on and off of Storage MirroringTo ensure protection of your data, Storage Mirroring offers multi-level security using native operating sy

3 - 3Managing the Management Console treeTo better manage the servers that appear in the Management Console, you can customize the server display to f

3 - 4ServersWithin your server groups, you have the ability to further manage the servers that are displayed by using the following functions.  Movin

3 - 5Removing serversTo remove a server, right-click on the server in the left or right pane of the Management Console and select Remove. You can also

3 - 6Storage Mirroring workspacesThe Management Console workspace contains the display of the panes of the Management Console and any servers that may

3 - 7Failover Control CenterFrom the Failover Control Center, you can manage, monitor, and control failover for your Storage Mirroring servers. The Fa

4 - 1Replication SetsA replication set defines the data on a source machine that Storage Mirroring protects. Replication sets are defined by volumes,

iiChapter 4 Replication Sets ...4-1Replication capabilities ...

4 - 2 Replication sets contain error checking to avoid inadvertent overwrites of the replication set rules. When replication sets are modified, a gen

4 - 3Replication capabilitiesStorage Mirroring replicates file and directory data stored on any Windows file system (FAT, FAT32, NTFS4, and NTFS5). Re

4 - 4f. Empty encrypted files will be mirrored to the target, but if you copy or create an empty encrypted file within the replication set after mirro

4 - 5Creating a replication setBefore you can establish a connection, you must create a replication set. 1. Highlight a source in the left pane of the

4 - 6Creating or modifying replication rules manuallyThere may be times when you cannot browse for data when creating a replication set. For example,

4 - 7Modifying a replication setStorage Mirroring allows you to make modifications to a replication set when you want to change the data you wish to p

4 - 8Calculating replication set sizeWhile Storage Mirroring is mirroring, the right pane of the Management Console displays statistics to keep you in

5 - 1Establishing a Connection Using the Connection WizardThe Connection Wizard guides you through the process of protecting your data. It helps you s

5 - 27. Select the location on the target where the data will be stored.  Send all data to a single path on the target—This option sends all select

6 - 1Establishing a Connection Using the Connection ManagerAfter you have created a replication set, you can establish a connection through the Connec

iiiChapter 11 Mirroring and Replication ...11-1Controlling mirroring ...

6 - 2 Mappings—You must specify the location on the target where the source’s replication set data will reside. Storage Mirroring offers two predefin

6 - 33. If desired, you can configure mirror settings before establishing your connection. Select the Mirroring tab on the Connection Manager.  Full

6 - 4 Send data only if Source is newer than Target—Only those files that are newer on the source are sent to the target.  Full—All files are sent

7 - 1Establishing a Connection Across a NAT or FirewallIf you are in an IPv4 environment and your source and target are on opposite sides of a NAT or

7 - 2Inserting the servers in the Management ConsoleManually insert your servers by selecting Insert, Server. Type the IP address of the router the se

8 - 1Establishing a Connection in a Cluster EnvironmentIn a MSCS cluster configuration, a single copy of data resides on a SCSI disk that is shared be

8 - 22. If your target is a cluster, create a virtual server (including resources for an IP address, network name, and physical disk) on the target cl

8 - 34. If your source is a cluster, you need to create a duplicate replication set on each of the other nodes in the cluster. Because the other nodes

8 - 45. On your cluster (source and/or target), you need to disable the standard Storage Mirroring connection controls so that the MSCS resource that

8 - 5f. Specify your Storage Mirroring connection parameters.  Replication Set—Select the Storage Mirroring replication set that you want to use

ivChapter 17 Failover for High Availability ...17-1Configuration requirements ...

8 - 6h. Specify your Storage Mirroring bandwidth limiting parameters.  No Bandwidth Limit—Data will be transmitted using all available bandwidth

9 - 1Simulating a ConnectionStorage Mirroring offers a simple way for you to simulate a connection in order to generate statistics that can be used to

9 - 2Establishing the simulated connectionAfter you have created a replication set, you can establish the simulated connection through the Connection

10 - 1Managing ConnectionsA unique connection ID is associated with each Storage Mirroring connection. The connection ID provides a reference point fo

10 - 2Monitoring connectionsWhen a source is highlighted in the left pane of the Management Console, the connections and their statistics are displaye

10 - 3Mirror Status  Mirroring—If the file size of the replication set has not been calculated and the data is being mirrored to the target machine,

10 - 4You can change the statistics that are displayed by selecting File, Options and selecting the Statistics tab. The statistics displayed in th

10 - 5Connection and Server Display LocationIcon or Color DescriptionIcons and colors displayed in the right pane when a server is highlighted in t

10 - 6You can configure when the icons and colors change to accommodate your network environment. For example, a slow or busy network may need longer

10 - 7Monitoring the message windowIn addition to the statistics and status shown in the Management Console, you can also open a message window to vie

vChapter 20 Server Settings ...20-1General ...

10 - 83. To change which server you are viewing messages for, select a different machine from the dropdown list on the toolbar. If necessary, the logi

10 - 9Queuing Storage Mirroring dataDuring the Storage Mirroring installation, you identified the amount of disk space that can be used for Storage Mi

10 - 10Configuring queuingYou should configure queuing on both the source and target. 1. Right-click the server on the left pane of the Management Con

10 - 114. Specify the Maximum system memory for queue. This is the amount of Windows system memory, in MB, that will be used to store data in queues.

10 - 12Configuring automatic reconnectionsWhile disk queues are user configurable and can be extensive, they are limited. If the amount of disk space

10 - 13Configuring compressionTo help reduce the amount of bandwidth needed to transmit Storage Mirroring data, compression allows you to compress dat

10 - 14Blocking target pathsYou can block writing to the paths on the target that contain the copy of the replication set data. This keeps the data fr

11 - 1Mirroring and ReplicationMirroring and replication are the key components of Storage Mirroring. This chapter contains information on the followi

11 - 2File Differences Mirror Options Compared Server Properties Source Tabaa. A checkmark enclosed in parentheses () indicates that the global o

11 - 3Controlling an automatic mirrorIn certain circumstances, for example if the disk-based queues on the source are exhausted, Storage Mirroring wil

1 - 1IntroductionStorage Mirroring is a real-time data replication and failover software product. Storage Mirroring augments your existing data protec

11 - 4 5. Click OK to save the settings. File Differences Remirror Options Compared NOTE: Database applications may update files without chang

11 - 5Configuring customized mirroring scriptsYou can customize your mirroring process by running customized scripts on the target at predefined point

11 - 6Configuring and removing orphan filesAn orphan file is a file that exists in the target’s copy of the replication set data, but it does not exis

11 - 73. Specify if you want to log the name of the orphan files to the Storage Mirroring log file on the target by marking Log Orphaned Files to Targ

12 - 1VerificationVerification is the process of confirming that the data on the target is identical to the data on the source. Verification creates

12 - 2Scheduled verificationVerification can be scheduled to occur automatically at periodic intervals. 1. Right-click the connection on the righ

12 - 3Verification logA verification log is created on the source during the verification process. The log identifies what is verified as well as whic

12 - 4Sample Verification Log  Timestamp—The last modified date and time of the file Size—The size, in bytes, of the file Mask—The attributes as

12 - 5e. Select Bin and the hexadecimal number will change to the binary equivalent.f. Pad the beginning of the binary equivalent with zeroes (0) so t

13 - 1Data TransmissionStorage Mirroring data is continuously transmitted to the target machine. Although the data may be queued if the network or tar

1 - 2The following diagram is one common Storage Mirroring configuration. Testing or MigrationOffsite Disaster High Availability CentralizedProduct

13 - 2Scheduling transmission criteriaUsing the Connection Manager Transmit tab, you can set start and stop criteria along with a schedule window.

13 - 3 Session Interval—This option begins transmitting Storage Mirroring data at specified intervals of time. This option is used in conjunction wit

13 - 4 Byte Limit—The byte limit specifies the maximum number of bytes that can be sent before ending the transmission session. When the byte limit

13 - 5Setting bandwidth limitationsBandwidth limitations are available to restrict the amount of network bandwidth used for Storage Mirroring data tra

13 - 6b. To limit the bandwidth usage, enter the maximum amount of data you want to transfer per second. You can indicate it by specifying your Connec

14 - 1SnapshotsA snapshot is an image of data taken at a single point in time. Snapshots allow you to view files and folders as they existed at points

14 - 2Understanding when to take a snapshotA snapshot may not necessarily be useful if the data on the target is in a bad state. You only want snapsho

14 - 3To be completely assured that your data on the target is good, automatic and scheduled snapshots only occur when the data is in a good Storage M

14 - 4failure. However, if your source is an application server and an operation has been dropped, that one file could cause the application not to st

14 - 5Scheduled snapshotsYou can schedule snapshots of your target data to fit your environment and needs. If the target data is in a bad state at the