NEC Storage ReplicationControl SQL Option User manual

NEC Storage ReplicationControl
SQL Option User's Manual

© NEC Corporation 2001-2003
No part of the contents of this book may be reproduced or
transmitted in any form without permission of NEC Corporation.
The contents of this book may be modified without notice in the future.

Preface
This manual describes the NEC Storage ReplicationControl SQL Option.
By being applied in combination with a data replication function (DynamicDataReplication or RemoteDataReplication),
this product makes it possible to create a snapshot without stopping operations for the Microsoft® SQL Server2000
database constructed on the NEC Storage series. This snapshot can be used for backups and parallel processing.
This enables 24-hour a day uninterrupted operation of the Microsoft SQL Server 2000 database.
If an error occurs while backing up the Microsoft SQL Server 2000 database using a data replication function, this product
is indispensable in recovering data up to the moment of error occurrence by applying the transaction log backup.
This manual is for readers who have basic knowledge of Microsoft SQL Server 2000 as well as experience with backup
recovery. The data replication functions in the NEC Storage series that are used in this manual, are explained in the “NEC
Storage Manager Data Replication User’s Manual”.
For information related to Microsoft SQL Server 2000, refer to the Microsoft SQL Server 2000 Books Online.
Refer to the “NEC Storage Manager Manual Guide” (IS901) for the overview of NEC Storage Manager and the related
manuals.
Remarks
1. This manual explains functions implemented by the following program products:
•NEC Storage Manager and NEC Storage BaseProduct
•NEC Storage ReplicationControl
•NEC Storage ReplicationControl SQL Option
•NEC Storage DynamicDataReplication
•NEC Storage RemoteDataReplication
2. This manual is applicable to the program products of the following versions:
•NEC Storage Manager Ver2.1
•NEC Storage BaseProduct Ver2.1
•NEC Storage ReplicationControl Ver2.1
•NEC Storage ReplicationControl SQL Option Ver2.1
3. The term “iSM” in this text refers to as all the NEC Storage Manager program products.
4. This manual is based on the Microsoft SQL Server 2000 Enterprise Edition and the Microsoft SQL Server
2000 Standard Edition.
5. The term “data replication functions” used in this text refers to the functions provided by the NEC Storage
DynamicDataReplication, NEC Storage RemoteDataReplication and NEC Storage ReplicationControl in
the NEC Storage series.
They differ from the “replication functions” provided by Microsoft SQL Server 2000.

6. The term “Microsoft SQL Server 2000” in this text refers to as either Microsoft SQL Server 2000
Enterprise Edition or the Microsoft SQL Server 2000 Standard Edition.
7. The term “MSCS” in this text refers to the Microsoft Cluster Server.
8. Trademarks and registered trademarks
•Microsoft® and Windows® are registered trademarks or trademarks of Microsoft Corporation in the
United States and other countries.
•VERITAS, Backup Exec, VERITAS Backup Exec, NetBackup, and VERITAS NetBackup are registered
trademarks or trademarks of VERITAS Software Corporation in the United States and other countries.
•ARCserve is a registered trademark of Computer Associates International, Inc. in the United States.
Other product names and company names, etc. are registered trademarks or trademarks of the associated
companies.
The First Edition in January 2002
The Fourth Edition in March 2003

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Contents
Chapter 1 Data Replication Overview ..............................................................................................................................1
1.1 Data Replication.......................................................................................................................................................... 1
1.2 Functions by Product .................................................................................................................................................. 2
1.3 Data Replication Advantages...................................................................................................................................... 4
1.4 Examples of Using Data Replication.......................................................................................................................... 6
Chapter 2 Overview of NEC Storage ReplicationControl SQL Option.........................................................................7
2.1 Product Function......................................................................................................................................................... 7
2.2 Advantages of NEC Storage ReplicationControl SQL Option................................................................................... 7
2.3 System Configuration ................................................................................................................................................. 8
2.4 Examples of Using NEC Storage ReplicationControl SQL Option ......................................................................... 10
2.4.1 Backup .............................................................................................................................................................. 10
2.4.2 Parallel Processing of Search Operations ......................................................................................................... 12
2.4.3 Parallel Processing of Operations Accompanied by Update ............................................................................ 13
Chapter 3 Database System Configuration .................................................................................................................... 14
3.1 Database Configuration ............................................................................................................................................ 14
3.2 Data Replication System Design .............................................................................................................................. 16
3.3 Application to Backup System.................................................................................................................................. 16
3.3.1 Backup Types.................................................................................................................................................... 16
3.4 Concept of Parallel Processing in Other Nodes........................................................................................................ 17
3.4.1 Standby Server.................................................................................................................................................. 17
3.4.2 Log Distribution................................................................................................................................................ 17
3.4.3 Server Accompanied by Update ....................................................................................................................... 17
3.4.4 Files Operated in Parallel.................................................................................................................................. 17
3.5 Operation Automatization......................................................................................................................................... 18
Chapter 4 Functions of NEC Storage ReplicationControl SQL Option......................................................................19
4.1 Snapshot Backup....................................................................................................................................................... 19
4.1.1 Snapshot Backup Operations ............................................................................................................................ 20
4.1.2 Snapshot Restore Operations ............................................................................................................................ 21
4.2 Commands ................................................................................................................................................................ 22
4.2.1 Snapshot Backup Command ............................................................................................................................. 22
4.2.2 Snapshot Restore Command............................................................................................................................. 30
4.3 Metafile Handling..................................................................................................................................................... 39
4.4 Access Restriction..................................................................................................................................................... 40
Chapter 5 Installation and Setting of NEC Storage ReplicationControl SQL Option............................................... 41
5.1 Operating Environment............................................................................................................................................. 41
5.2 Software Installation................................................................................................................................................. 41
5.3 Software Uninstallation ............................................................................................................................................ 42
5.4 Software Update........................................................................................................................................................ 42
5.5 Setting of NEC Storage ReplicationControl SQL Option ........................................................................................ 42
5.5.1 Replication Volume Preparation....................................................................................................................... 43
5.5.2 Database Creation ............................................................................................................................................. 43
5.5.3 Volume Assignment for Metafiles.................................................................................................................... 43
5.6 Setting of Microsoft SQL Server 2000..................................................................................................................... 43
5.6.1 Change of Worker Thread Maximum Number................................................................................................. 44
Chapter 6 Operations of NEC Storage ReplicationControl SQL Option....................................................................45
6.1 Tape Backup ............................................................................................................................................................. 45
6.1.1 Backup .............................................................................................................................................................. 46

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6.1.2 Multiple Database Backup................................................................................................................................ 50
6.1.3 Recovery ........................................................................................................................................................... 55
6.1.4 Multiple Database Recovery............................................................................................................................. 60
6.2 Disk Backup.............................................................................................................................................................. 65
6.2.1 Preparation........................................................................................................................................................ 65
6.2.2 Backup .............................................................................................................................................................. 66
6.2.3 Recovery ........................................................................................................................................................... 71
6.3 Parallel Operation on Another Node......................................................................................................................... 75
6.3.1 Operation as Standby Database......................................................................................................................... 75
6.3.2 Log Distribution................................................................................................................................................ 78
6.3.3 Operation for Server Accompanied by Update................................................................................................. 79
Chapter 7 Measures for Errors........................................................................................................................................82
7.1 Error Detection Method............................................................................................................................................ 82
7.2 Errors Related to Database Configurations............................................................................................................... 82
7.3 Errors Related to Metafile Configurations................................................................................................................ 83
Appendix A Notes.............................................................................................................................................................84
Index......................................................................................................................................................................................... 86

Chapter 1 Data Replication Overview
1
Chapter 1 Data Replication Overview
To centrally manage the enormous amount of information accumulated by business operations and promote its
effective and efficient utilization, it is necessary to have a storage system that realizes a highly advanced
processing feature, large capacity memory and high reliability. The purpose of the data replication function is to
effectively operate this storage system.
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Data replication, which is a function that creates a Replication Volume (RV) for a Business Volume
(MV: Master Volume), is stored in the disk array. The RV can achieve synchronization and segregation
from the MV at an arbitrary time. When synchronized, the MV and RV coincide with each other in
terms of their contents; thus, update the MV is instantly reflected in the RV. Through segregation at an
arbitrary time, the MV data can be kept in the RV. By using this RV, backup and searches can be
performed in parallel with on-line services, thus making it possible to increase online operation time.
Figure 1-1 Data Replication
NEC Storage DynamicDataReplication
Synchronization /
Segregation operations
NEC Storage RemoteDataReplication
Maste
r
Volume
(
MV
)
Replication
Volume
(
RV
)
Parallel processing
(Backup/Search)
Master operations
(Online)
Business Server
Maste
r
Volume
(
MV
)
Replication
Volume
(
RV
)

Chapter 1 Data Replication Overview
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The following products are available for data replication.
•NEC Storage DynamicDataReplication (DDR), NEC Storage DynamicDataReplication Ver2 (DDR
Ver2)
Creates an RV in the same disk array.
Supported by the NEC Storage2000/3000/4000 series
•NEC Storage RemoteDataReplication (RDR), NEC Storage RemoteDataReplication Ver2 (RDR
Ver2)
Creates an RV between different disk arrays.
Supported by the NEC Storage3000/4000 series.
* The replication management function in NEC Storage Manager can be used by introducing NEC
Storage DynamicDataReplication or NEC Storage RemoteDataReplication.
•NEC Storage ReplicationControl
Operates the replication function. Provides the CLI (Command Line Interface) and the API
(Application Program Interface).
•NEC Storage ReplicationControl SQL Option
Creates a snapshot without stopping operations on Microsoft SQL Server 2000 database constructed
on the NEC Storage series.

Chapter 1 Data Replication Overview
3
The NEC Storage Manager product provides functions for the administrator to understand the disk
array configuration and operating state of the NEC Storage series with ease. The following products are
available for NEC Storage Manager.
•NEC Storage Manager
Displays the components of the disk array ,monitors its state and notifies of its failure.
•NEC Storage PerformanceMonitor
Monitors the performance of the disk array, collects its performance information and displays its
performance on a real-time basis.
Figure 1-2 Functions by Product
NEC Storage ReplicationControl
NEC Storage
DynamicDataReplication
NEC Storage
RemoteDataReplication
NEC Storage Manager Server
NEC Storage Manager Client
NEC Storage ReplicationControl
SQL Option

Chapter 1 Data Replication Overview
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Data replications have the following advantages.
•Can create replications of a randomly selected MV at an arbitrary time.
−Can disconnect the RV at an arbitrary time to use for another purpose.
−At the time of resynchronization, synchronization is achieved in a short time by the update
differential management function.
−Up to three RVs can be created.
Figure 1-3 Data Replication operation
•Provides the NEC Storage DynamicDataReplication in a disk array and the NEC Storage
RemoteDataReplication between the disk arrays with the same visibility (operability).
•Considering reliability, the RAID configuration is adopted for replications as well.
−It is also possible to set a RAID type that differs from the original volume.
•Integrated control by NEC Storage Manager (GUI)
MV RV
Disconnects replications at an arbitrary time to use
for another purpose.
MV RV
Reflects the update information
successively.
Co
py
in
g
Disconnect
Creates replications
instantly.
Resynchronized in a
short time through
differential
reflection.
■Connected ■Disconnected
U
p
date U
p
date
Update
differential
· Manages the respective update information of
MVs and RVs as update differentials.
·With the update differential management function,
only the updated data is reflected, and the processing time can be
reduced. Since coinciding is processed in parallel with the MV access
in the disk array, it is wait until the differential data is completed.
·It is also possible to resynchronize with (restore to) the status of the RV.
AP AP backup
Resynchronization

Chapter 1 Data Replication Overview
5
NEC Storage Series
NEC Storage Manager
Operation Status Display Window
List Display Window
−Can unify the management of data replications by using NEC Storage Manager. Can display and
set the operational states of data replications through graphical interfaces.
Figure 1-4 Data Replication operation Display
•Business Link
−Can perform automatic operations based on linkage between backup software and job scheduling
software by using the CLI for NEC Storage ReplicationControl.

Chapter 1 Data Replication Overview
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The RV that has been separated from the MV at an arbitrary time by using the data replication function
can be used for other purposes. Because the disconnected RV is independent from the MV, using the
RV will bring the following effects:
•Backup
−High-speed backup
Online data replications can be created through simple operations. These replications can be
used as backups as they are. As the replications are created in the disk array they do not affect
the online system.
−Backup in parallel with online service
Saving to tapes, etc. can be done from RVs in parallel with MVs, thus making it unnecessary to
worry about online responses during saving.
•Parallel processing
−Executes the online and the search work simultaneously.
By making the RV data independent for the search work, the update work and the search work
can be operated without interference, thus solving the problem of competing for disk access and
the resulting deadlock.
−Simultaneous execution of batch processing
Execution time of batch processing can be substantially shortened by using RV.
•Constructing an evaluation environment
−Application evaluation
An environment for application evaluation can be constructed with ease by using an RV.

Chapter 2 Overview of NEC Storage ReplicationControl SQL Option
7
Chapter 2 Overview of NEC Storage
ReplicationControl SQL Option
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By applying NEC Storage ReplicationControl SQL Option product in combination with the data
replication (NEC Storage DynamicDataReplication or NEC Storage RemoteDataReplication), the
Microsoft SQL Server 2000 database built on the NEC Storage series is able to create a snapshot
without suspending operations. Also, the snapshot is available in backup or parallel processing.
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NEC Storage ReplicationControl SQL Option enables round-the-clock, uninterruptible operation using
the Microsoft SQL Server 2000 database.
If an error occurs while backing up the Microsoft SQL Server 2000 database using a data replication,
NEC Storage ReplicationControl SQL Option is indispensable in recovering the data up to the moment
of error occurrence by applying the transaction log backup.

Chapter 2 Overview of NEC Storage ReplicationControl SQL Option
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NEC Storage
Re
p
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NEC Storage
Re
p
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DB
(
MV
)
NEC Storage Manager
LAN
NEC Storage DynamicDataReplication
Microsoft
SQL Server2000
NEC Storage RemoteDataReplication
NEC Storage ReplicationControl SQL Option
Figure 2-1 System Configuration
To install and use the data replication, the following hardware devices are required.
(1) Disk array (NEC Storage Series)
The NEC Storage3000/4000 series disk array (the Replication Director is required separately)
equipped with a data replication (NEC Storage DynamicDataReplication; NEC Storage
RemoteDataReplication), or the NEC Storage 2000 series disk array applies.
(2) Management Server
Manages the data replication.
(3) Business Server
Operates data replications.
(4) Backup Server
Backs up data.
Business Server Backup Server
This product Backu
p
software
Tape drive
Management
Serve
r
Replication operation
NEC Storage series
(RV)
Volume
Replication

Chapter 2 Overview of NEC Storage ReplicationControl SQL Option
9
The software performing data replication consists of the following components.
(1) NEC Storage ReplicationControl SQL Option
Makes it possible to make a snapshot without suspending operation of the Microsoft SQL Server
2000 database.
(2) NEC Storage ReplicationControl
Provides the command that checks the replication operation and state from the business server.
(3) NEC Storage Manager
Provides the function to display the operation status of NEC Storage DynamicDataReplication
and NEC Storage RemoteDataReplication and the pair volume settings. Installing NEC Storage
DynamicDataReplication and NEC Storage RemoteDataReplication makes it possible to use the
replication management function incorporated in the NEC Storage Manager.
(4) NEC Storage DynamicDataReplication
A function that facilitates data replication between the same disk arrays.
(5) NEC Storage RemoteDataReplication
A function that facilitates data replication between the different disk arrays.
The NEC Storage ReplicationControl SQL Option product operates in linkage with either of the
Microsoft software programs below.
(1) Microsoft SQL Server 2000 Enterprise Edition
(2) Microsoft SQL Server 2000 Standard Edition

Chapter 2 Overview of NEC Storage ReplicationControl SQL Option
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The operational application of making backup copies using an RV is described below.
(1) Backup from an RV to a magnetic tape medium
This is the backing up of an RV for an MV to a magnetic tape medium.
By synchronizing and separating the MV and the RV during the time period when the load on the
business operations that use the Microsoft SQL Server 2000 is lower, it is possible to back up
copies onto magnetic tape media without suspending the operations.
Since backup copies are made from RVs, MVs are not affected.
Figure 2-2 Backup from RVs
(a) During operation, keep the MV and the RV separate.
(b) If the load is lowered, synchronize and separate the MV and the RV.
(c) Execute the backup work concurrently with the business operation by using the separated
RV. After the backup is completed, the separated RV can be used as a disk backup.
Business Server Backup Server
Master
Volume
(MV)
Replication
Volume
(
RV
)
ProductionTas
k
Connected
Backup
Separated
Tape

Chapter 2 Overview of NEC Storage ReplicationControl SQL Option
11
(2) Using as a disk backup
This refers to the use of an RV as a backup copy of an MV. This can be used as a disk medium
backup without suspending operations because the MV and the RV are synchronized and
separated during the time period when the load on the business operations that use the Microsoft
SQL Server 2000 is lower.
When restoring data from the backup data, it is possible to use backup data even if data from the
RV to the MV is not completely copied. In the event that the data to access is not restored to the
MV, restoration is realized through data access to the RV, thus making it unnecessary for the user
to think about whether to use the MV or the RV.
This makes it becomes possible to substantially reduce the data recovery time.
Figure 2-3 Use of RV as Backup
(a) During operation, keep all MVs and RVs separate.
(b) If the load is lowered, synchronize and separate MV1 and RV1.
(c) Make backup copies by using RV1, RV2 and RV3 in order.
Master
Volume
(
MV
)
Separate
Connect/Separate
Separate Separate
Separate
Connect/
Separate
Master
Volume
(MV)
Replication
Volume 1
(RV1)
Replication
Volume 2
(RV2)
Replication
Volume 3
(RV3)
Replication
Volume 1
(RV1)
Replication
Volume 2
(RV2)
Replication
Volume 3
(RV3)

Chapter 2 Overview of NEC Storage ReplicationControl SQL Option
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By creating an RV of the business operation database, the database can be separated into different
volumes to execute the update work and the search work respectively. This makes it becomes possible
to execute the database search work without affecting the database update work.
The NEC Storage ReplicationControl SQL Option must be installed on the server performing the search
work.
The search work uses the standby database function on the Microsoft SQL Server 2000.
Figure 2-4 Parallel processing of Search Work
(a) When starting search work, the MV and the RV are synchronized and separated.
(b) Hereafter is applying the transaction log backup reflects, the updated part of the business
operation volume.
Master
database
Run as standby
data base
Af
ter the business o
p
eration is started
When starting the business operation
Reflecting the
update part
Update
work
Applying the
transaction log
Search
work
Maste
r
Volume
(
MV
)
Replication
Volume
(
RV
)
Connect/
separate Maste
r
Volume
(
MV
)
Replication
Volume
(
RV
)
Master
database

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p
pd
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By creating and separating an RV of the business operation database, the database can be used by other
servers. This is used for constructing test environments.
When constructing an environment, replications of the database can be made without suspending
operations using the Microsoft SQL Server 2000. When the business operations load is lower, the MV
and the RV are synchronized and separated.
Figure 2-5 Parallel processing of Operations Accompanied by Update
(a) During the daytime, keep the MV and the RV separate.
(b) During the nighttime, stop parallel operation, synchronize and separate the MV and the RV.
(c) Execute the operation DB and the replication DB in parallel. (RV being the data of the previous
day)
Reflecting the
updated part
N
i
g
httim
e
Data from previous day
Update
work
Connect
D
a
y
tim
e
Search
work
Maste
r
Volume
(
MV
)
Replication
Volume
(
RV
)
Business
Volume
(
MV
)
Master
database
Master
database
Separate
Replication
Volume
(
RV
)

Chapter 3 Database System Configuration
14
Chapter 3 Database System Configuration
Database configuration and concept of backups for the Microsoft SQL Server 2000 are briefly described below.
For details, refer to the Microsoft SQL Server 2000 Books Online.
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The Microsoft SQL Server 2000 database consists of three files; the primary data file, the secondary
data file and the log file. The primary data file and the secondary data file are also simply called “data
file”.
Figure 3-1 Database Configuration
•Primary data file
One database always has one primary data file. As the starting point of the database, the primary
data file points to the locations of the secondary data and log files (File1.mdf in the diagram above).
The file name extension for the primary data file is .mdf.
•Secondary data file
As a data file, the secondary data file sometimes does not exist and sometimes multiple secondary
data files exist (File2.ndf, File3.ndf and File4.ndf).
The extension for the secondary data file is normally .ndf.
•Log file
Refers to the file where the log for recovery is stored. At least one file is required; sometimes, two or
more files also exist (File1.ldf and File2.ldf in the diagram above).
The file name extension for the log file is normally .ldf.
File group 1
File group 2
File1.mdf File2.ndf File3.ndf File4.ndf File1.ldf File2.ldf
Data file Log file
Database