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Backup and Recovery - 1

© 2006 EMC Corporation. All rights reserved.

Backup and RecoveryBackup and Recovery

Module 4.2



© 2006 EMC Corporation. All rights reserved. Backup and Recovery - 2

Backup and Recovery

Upon completion of this module, you will be able to:

Describe best practices for planning Backup and Recovery.

Describe the common media and types of data that are part of a Backup and Recovery strategy.

Describe the common Backup and Recovery topologies.

Describe the Backup and Recovery Process.

Describe Management considerations for Backup and Recovery.

This lesson looks at Backup and Recovery. Backup and Recovery are a major part of the planning for Business Continuity.




In this module …

This module contains the following lessons:

Planning for Backup and Recovery

Backup and Recovery Methods

Backup Architecture Topologies

Managing the Backup Process

The lessons in this course will provide an overview of Backup and Recovery including the business and technical aspects.




Lesson: Planning for Backup and RecoveryUpon completion of this lesson, you be able to:

Define Backup and Recovery.

Describe common reasons for a Backup and Recovery plan.

Describe the business considerations for Backup and Recovery.

Define RPO and RTO.

Describe the data considerations for Backup and Recovery

Describe the planning for Backup and Recovery.

This lesson provides an overview of the business drivers for backup and recovery and introduces some of the common terms used when developing a backup and recovery plan.




What is a Backup?

Backup is an additional copy of data that can be used for restore and recovery purposes.

The Backup copy is used when the primary copy is lost or corrupted.

This Backup copy can be created as a:– Simple copy (there can be one or more copies)– Mirrored copy (the copy is always updated with whatever is written

to the primary copy.)

A Backup is a copy of the online data that resides on primary storage. The backup copy is created and retained for the sole purpose of recovering deleted, broken, or corrupted data on the primary disk.

The backup copy is usually retained over a period of time, depending on the type of the data, and on the type of backup. There are three derivatives for backup: disaster recovery, Archival, and operational backup. We will review them in more detail, on the next slide.

The data that is backed up may be on such media as disk or tape, depending on the backup derivative the customer is targeting. For example, backing up to disk may be more efficient than tape in operational backup environments.




Backup and Recovery Strategies

Several choices are available to get the data to the backup media such as:

Copy the data.

Mirror (or snapshot) then copy.

Remote backup.

Copy then duplicate or remote copy.

Several choices are available to get the data written to the backup media. 1. You can simply copy the data from the primary storage to the secondary storage (disk or

tape), onsite. This is a simple strategy, easily implemented, but impacts the production server where the data is located, since it will use the server’s resources. This may be tolerated on some applications, but not high demand ones.

2. To avoid an impact on the production application, and to perform serverless backups, you can mirror (or snap) a production volume. For example, you can mount it on a separate server and then copy it to the backup media (disk or tape). This option will completely free up the production server, with the added infrastructure cost associated with additional resources.

3. Remote Backup, can be used to comply with offsite requirements. A copy from the primary storage is done directly to the backup media that is sitting on another site. The backup media can be a real library, a virtual library or even a remote filesystem.

4. You can do a copy to a first set of backup media, which will be kept onsite for operational restore requirements, and then duplicate it to another set of media for offsite purposes. To simplify thr procedure, you can replicate it to an offsite location to remove any manual procedures associated with moving the backup media to another site.




It’s All About Recovery!

Businesses back up their data to enable its recovery in case of potential loss.

Businesses also back up their data to comply with regulatory requirements.

Types of backup derivatives:– Disaster Recovery– Archival– Operational

Disaster Recovery addresses the requirement to be able to restore all, or a large part of, an IT infrastructure in the event of a major disaster.

Archival is a common requirement used to preserve transaction records, email, and other business work products for regulatory compliance. The regulations could be internal, governmental, or perhaps derived from specific industry requirements.

Operational is typically the collection of data for the eventual purpose of restoring, at some point in the future, data that has become lost or corrupted.




Reasons for a Backup Plan

Hardware Failures

Human Factors

Application Failures

Security Breaches

Disasters

Regulatory and Business Requirements

Reasons for a backup plan include: Physical damage to a storage element (such as a disk) that can result in data loss. People make mistakes and unhappy employees or external hackers may breach security and maliciously destroy data. Software failures can destroy or lose data and viruses can destroy data, impact data integrity, and halt key operations. Physical security breaches can destroy equipment that contains data and applications.Natural disasters and other events such as earthquakes, lightning strikes, floods, tornados, hurricanes, accidents, chemical spills, and power grid failures can cause not only the loss of data but also the loss of an entire computer facility. Offsite data storage is often justified to protect a business from these types of events.Government regulations may require certain data to be kept for extended timeframes. Corporations may establish their own extended retention policies for intellectual property to protect them against litigation. The regulations and business requirements that drive data as an archive generally require data to be retained at an offsite location.




How does Backup Work?

Client/Server Relationship

Server – Directs Operation– Maintains the Backup Catalog

Client– Gathers Data for Backup (a backup client sends backup data to a

backup server or storage node).

Storage Node

Backup products vary, but they do have some common characteristics. The basic architecture of a backup system is client-server, with a backup server and some number of backup clients or agents. The backup server directs the operations and owns the backup catalog (the information about the backup). The catalog contains the table-of-contents for the data set. It also contains information about the backup session itself.

The backup server depends on the backup client to gather the data to be backed up. The backup client can be local or it can reside on another system, presumably to backup the data visible to that system. A backup server receives backup metadata from backup clients to perform its activities.

There is another component called a storage node. The storage node is the entity responsible for writing the data set to the backup device. Typically there is a storage node packaged with the backup server and the backup device is attached directly to the backup server’s host platform. Storage nodes play an important role in backup planning as it can be used to consolidate backup servers.




How does Backup Work, continued

DiskStorage

TapeBackup

Data SetMetadataCatalog

Backup Server& Storage Node

Servers Backup Clients

Clients

The following represents a typical Backup process:The Backup Server initiates the backup process (starts the backup application). The Backup Server sends a request to a server to “send me your data”.The server sends the data to the Backup Server and/or Storage Node.The Storage Node sends the data to the tape storage device and the Backup Server begins building the catalog (metadata) of the backup session.When all of the data has been transferred from the server to the Backup Server, the Backup Server writes the catalog to a disk file and closes the connection to the tape device.




Business Considerations

Customer business needs determine:– What are the restore requirements – RPO & RTO?– Where and when will the restores occur?– What are the most frequent restore requests?– Which data needs to be backed up?– How frequently should data be backed up?

hourly, daily, weekly, monthly– How long will it take to backup?– How many copies to create?– How long to retain backup copies?

Some important decisions that need consideration before implementing a Backup/Restore solution are shown above. Some examples include:

The Recovery Point Objective (RPO)The Recovery Time Objective (RTO)The media type to be used (disk or tape) Where and when the restore operations will occur – especially if an alternative host will be used to receive the restore data.When to perform backups.The granularity of backups – Full, Incremental or cumulative.How long to keep the backup – for example, some backups need to be retained for 4 years, others just for 1 month Is it necessary to take copies of the backup or not




Data Considerations: File Characteristics

Location

Size

Number

Location: Many organizations have dozens of heterogeneous platforms that support a complex application. Consider a data warehouse where data from many sources is fed into the warehouse. When this scenario is viewed as “The Data Warehouse Application”, it easily fits this model. Some of the issues are:−How the backups for subsets of the data are synchronized−How these applications are restored

Size: Backing up a large amount of data that consists of a few big files may have less system overhead than backing up a large number of small files. If a file system contains millions of small files, the very nature of searching the file system structures for changed files can take hours, since the entire file structure is searched. Number: a file system containing one million files with a ten-percent daily change rate will potentially have to create 100,000 entries in the backup catalog. This brings up other issues such as:−How a massive file system search impacts the system− Search time/Media impact− Is there an impact on tape start/stop processing?




Data Considerations: Data Compression

Compressibility depends on the data type, for example:

Application binaries – do not compress well.

Text – compresses well.

JPEG/ZIP files – are already compressed and expand if compressed again.

Many backup devices such as tape drives, have built-in hardware compression technologies. To effectively use these technologies, it is important to understand the characteristics of the data. Some data, such as application binaries, do not compress well. Text data can compress very well, while other data, such as JPEG and ZIP files, are already compressed.




Data Considerations: Retention Periods

Operational– Data sets on primary media (disk) up to the point where most restore

requests are satisfied, then moved to secondary storage (tape).

Disaster Recovery– Driven by the organization’s disaster recovery policy

Portable media (tapes) sent to an offsite location / vault.Replicated over to an offsite location (disk).Backed up directly to the offsite location (disk, tape or emulated tape).

Archiving– Driven by the organization’s policy.– Dictated by regulatory requirements.

As mentioned before, there are three types of backup models (Operational, Disaster Recovery, and Archive). Each can be defined by its retention period. Retention Periods are the length of time that a particular version of a dataset is available to be restored.

Retention periods are driven by the type of recovery the business is trying to achieve:For operational restore, data sets could be maintained on a disk primary backup storage target for a period of time, where most restore requests are likely to be achieved, and then moved to a secondary backup storage target, such as tape, for long term offsite storage.For disaster recovery, backups must be done and moved to an offsite location. For archiving, requirements usually will be driven by the organization’s policy and regulatory conformance requirements. Tapes can be used for some applications, but for others a more robust and reliable solution, such as disks, may be more appropriate.




Lesson: Summary Topics in this lesson included:

Backup and Recovery definitions and examples.

Common reasons for Backup and Recovery.

The business considerations for Backup and Recovery.

Recovery Point Objectives and Recovery Time Objectives.

The data considerations for Backup and Recovery

The planning for Backup and Recovery.

In this lesson we reviewed the business and data considerations when planning for Backup and Recovery including:

What is a Backup and Recovery?

What is the Backup and Recovery process?

Business recovery needsRPO Recovery point objectivesRTO Recovery time objectives

Data characteristics Files, compression, retention




Lesson: Backup and Recovery Methods Upon completion of this lesson, you be able to:

Describe Hot and Cold Backups.

Describe the levels of Backup Granularity.

We’ve discussed the importance and considerations for a Backup Plan, now this lesson provides an overview of the different methods for creating a backup set.




Database Backup Methods

Hot Backup: production is not interrupted.

Cold Backup: production is interrupted.

Backup Agents manage the backup of different data types such as:– Structured (such as databases)– Semi-structured (such as email)– Unstructured (file systems)

Backing up databases can occur useing two different methods:A Hot backup, which means that the application is still up and running, with users accessing it, while backup is taking place.A Cold backup, which means that the application will be shut down for the backup to take place.

Most backup applications offer various Backup Agents to do these kinds of operations. There will be different agents for different types of data and applications.




Backup Granularity and LevelsFull Backup

Cumulative (Differential)

Incremental

Full Cumulative Incremental

The granularity and levels for backups depend on business needs, and, to some extent, technological limitations. Some backup strategies define as many as ten levels of backup. IT organizations use a combination of these to fulfill their requirements. Most use some combination of Full, Cumulative, and Incremental backups.

A Full backup is a backup of all data on the target volumes, regardless of any changes made to the data itself.

An Incremental backup contains the changes since the last backup, of any type, whichever was most recent.

A Cumulative backup, also known as a Differential backup, is a type of incremental that contains changes made to a file since the last full backup.




Files 1, 2, 3, 4, 5

ProductionProduction

Restoring an Incremental Backup

Key Features– Files that have changed since the last full or incremental backup are

backed up.– Fewest amount of files to be backed up, therefore faster backup and less

storage space.– Longer restore because last full and all subsequent incremental backups

must be applied.

IncrementalIncremental

Tuesday

File 4


Wednesday

File 3


Thursday

File 5Files 1, 2, 3

Monday

Full BackupFull Backup

Following is an example of an incremental backup and restore:

1. A full backup of the business data is taken on Monday evening. Each day after that, an incremental backup is taken. These incremental backups only backup files that are new or that have changed since the last full or incremental backup.

2. On Tuesday, a new file is added, File 4. No other files have changed. Since File 4 is a new file added after the previous backup on Monday evening, it will be backed up Tuesday evening.

3. On Wednesday, there are no new files added since Tuesday, but File 3 has changed. Since File 3 was changed after the previous evening backup (Tuesday), it will be backed up Wednesday evening.

4. On Thursday, no files have changed but a new file has been added, File 5. Since File 5 was added after the previous evening backup, it will be backed up Thursday evening.

5. On Friday morning, there is a data corruption, so the data must be restored from tape. a. The first step is to restore the full backup from Monday evening. Then, every incremental

backup that was done since the last full backup must be applied, which, in this example, means the:

b. Tuesday, c. Wednesday, and d. Thursday incremental backups.




Restoring a Cumulative Backup

Key Features– More files to be backed up, therefore it takes more time to backup

and uses more storage space.– Much faster restore because only the last full and the last cumulative

backup must be applied.

Files 1, 2, 3, 4, 5, 6


CumulativeCumulative

Tuesday

File 4Files 1, 2, 3

Monday

Full BackupFull Backup CumulativeCumulative

Wednesday

Files 4, 5

CumulativeCumulative

Thursday

Files 4, 5, 6

The following is an example of cumulative backup and restore:

1. A full backup of the data is taken on Monday evening. Each day after that, a cumulative backup is taken. These cumulative backups backup ALL FILES that have changed since the LAST FULL BACKUP.

2. On Tuesday, File 4 is added. Since File 4 is a new file that has been added since the last full backup, it will be backed up Tuesday evening.

3. On Wednesday, File 5 is added. Now, since both File 4 and File 5 are files that have been added or changed since the last full backup, both files will be backed up Wednesday evening.

4. On Thursday, File 6 is added. Again, File 4, File 5, and File 6 are files that have been added or changed since the last full backup; all three files will be backed up Thursday evening.

5. On Friday morning, there is a corruption of the data, so the data must be restored from tape. a. The first step is to restore the full backup from Monday evening. b. Then, only the backup from Thursday evening is restored because it contains all the

new/changed files from Tuesday, Wednesday, and Thursday.





Hot and Cold Backups.

The levels of Backup Granularity.

This lesson provided an introduction to Backup methods and granularity levels.




Lesson: Backup Architecture Topologies Upon completion of this lesson, you be able to:

Describe DAS, LAN, SAN, Mixed topologies.

Describe backup media considerations.

So far, we have discussed the importance of the Backup plan and the different methods used when creating a backup set. This lesson provides an overview of the different topologies and media types that are used to support creating a backup set.




Backup Architecture Topologies

There are 3 basic backup topologies:– Direct Attached Based Backup– LAN Based Backup– SAN Based Backup

These topologies can be integrated, forming a “mixed”topology

There are three basic topologies that are used in a backup environment: Direct Attached Based Backup, LAN Based Backup, and SAN Based Backup.

There is also a fourth topology, called “Mixed”, which is formed when mixing two or more of these topologies in a given situation.




Direct Attached Based Backups

Catalog

Backup Server

LAN

Metadata

MediaBackupStorage Node

Backup Client

Data

Here, the backup data flows directly from the host to be backed up to the tape, without utilizing the LAN. In this model, there is no centralized management and it is difficult to grow the environment.




LAN Based Backups

Backup ServerStorage Node

LAN

Metadata

Storage Node

Data

Mail ServerBackup Client

Database ServerBackup Client

MetadataData

In this model, the backup data flows from the host to be backed up to the tape through the LAN. There is centralized management, but there may be an issue with the LAN utilization since all data goes through it.




SAN Based Backups (LAN Free)

LAN

Metadata

Storage NodeBackup Client

Data

Mail Server

SAN

Backup Server

Data

Backup Device

A SAN based backup, also known as LAN Free backup, is achieved when there is no backup data movement over the LAN. In this case, all backup data travels through a SAN to the destination backup device.

This type of backup still requires network connectivity from the Storage Node to the Backup Server, since metadata always has to travel through the LAN.




SAN/LAN Mixed Based Backups

LAN

Metadata

Storage Node

Data

Mail ServerBackup Client

Database ServerBackup Client

Data

SAN

Backup Server

Data

Backup Device

A SAN/LAN Mixed Based Backup environment is achieved by using two or more of the topologies described in the previous slides. In this example, some servers are SAN based while others are LAN based.




Backup Media

Tape– Traditional destination for backups– Sequential access– No protection

Disk– Random access– Protected by the storage array (RAID, hot spare, etc)




Multiple Streams on Tape Media

Multiple streams interleaved to achieve higher throughput on tape

– Keeps the tape streaming, for maximum write performance– Helps prevent tape mechanical failure– Greatly increases time to restore

TapeTape

Data fromStream 1 Data from

Stream 2 Data fromStream 3

Tape drive streaming is recommended from all vendors, in order to keep the drive busy. If you do not keep the drive busy during the backup process (writing), performance will suffer. Multiple streaming helps to improve performance drastically, but it generates one issue as well: the backup data becomes interleaved, and thus the recovery times are increased.




Backup to Disk

Backup to disk minimizes tape in backup environments by using disk as the primary destination device– Cost benefits– No processes changes needed– Better service levels

Backup to disk aligns backup strategy to RTO and RPO

Backup to disk replaces tape and its associated devices, as the primary target for backup, with disk. Backup to disk systems offer major advantages over equivalent scale tape systems, in terms of capital costs, operating costs, support costs, and quality of service. It can be implemented fully on day 1 or over a phased approach.




Tape versus Disk – Restore Comparison

Typical Scenario:800 users, 75 MB mailbox 60 GB database

Source: EMC Engineering and EMC IT

*Total time from point of failure to return of service to e-mail users

31

0 10 20 30 40 50 60 70 80 90 100 120110Recovery Time in Minutes*

TapeBackup / Restore

DiskBackup / Restore

108Minutes

108Minutes

24Minutes

24Minutes

This example shows a typical recovery scenario using tape and disk. As you can see, recovery with disk provides much faster recovery than does recovery with tape.




Three Backup / Restore Solutions based on RTO

Time of last image dictates the log playback timeLarger data sets extend the recovery time (ATA and tape)

*Total time from point of failure to return of service to e-mail users

0 10 20 30 40 50 60 70 80 90 100 120110Recovery Time in Minutes*

Backup on tape

Backup on ATA

108 Min.108 Min.

24 Min.24 Min.

Typical Scenario:800 users, 75 MB mailbox 60 GB DB – restore time500 MB logs – log playback

130

Local Replica / Clone

2 Min.

41 Minutes

19 Minutes

125 Minutes

17 Min.

17 Min.

17 Min.

Restore time

Log playback

The diagram shows typical recovery scenarios using different technical solutions. As you can see recovery with a Local Replica or clones provides the quickest recovery method.

It is important to note that using clones on Disk, enables you to be able to make more copies of your data more often. This will improve RPO (the point from which they can recover). It will also improve RTO because the log files will be smaller and that will reduce the log playback time.




Traditional Backup, Recovery and Archive Approach

Production environment grows– Requires constant tuning and data placement to

maintain performance – Need to add more tier-1 storage

Backup environment grows– Backup windows get longer and jobs do not complete– Restores take longer– Requires more tape drives and silos to keep up with

service levels

Archive environment grows– Impact flexibility to retrieve content when requested– Requires more media, adding management cost– No investment protection for long term retention

requirements

BackupProcessBackupProcess

ArchiveProcessArchiveProcess


In a traditional approach for backup and archive, businesses take a backup of production. Typically backup jobs use weekly full backups and nightly incremental backups. Based on business requirements, they will then copy the backup jobs and eject the tapes to have them sent offsite, where they will be stored for a specified amount of time.

The problem with this approach is simple - as the production environment grows, so does the backup environment.




Differences Between Backup / Recovery & ArchiveBackup / Recovery ArchiveA secondary copy of information Primary copy of information

Used for recovery operations Available for information retrieval

Improves availability by enabling application to be restored to a specific point in time

Adds operational efficiencies by moving fixed / unstructured content out of operational environment

Typically short-term (weeks or months)

Typically long-term (months, years, or decades)

Data typically overwritten on periodic basis (e.g., monthly)

Data typically maintained for analysis, value generation, or compliance

Not for regulatory compliance—though some are forced to use

Useful for compliance and should take into account information-retention policy

Backup/Recovery and Archiving support different business and goals. This slide compares and contrasts some of the differences that are significant.




New Architecture for Backup, Recovery & Archive

Understand the environment

Actively archive valuable information to tiered storage

Back up active production information to disk

Retrieve from archive or recover from backup

BackupProcessBackupProcess

ArchiveProcessArchiveProcessProductionProduction

1

3

4

2

4

The recovery process is much more important than the backup process. It is based on the appropriate recovery-point objectives (RPOs) and recovery-time objectives (RTOs). The process usually drives a decision to have a combination of technologies in place, from online local replicas, to backup to disk, to backup to tape for long-term, passive RPOs. Archive processes are determined not only by the required retention times, but also by retrieval-time service levels and the availability requirements of the information in the archive. For both processes, a combination of hardware and software is needed to deliver the appropriate service level. The best way to discover the appropriate service level is to classify the data and align the business applications with it.





The DAS, LAN, SAN, and Mixed topologies.

Backup media considerations.

This lesson provided an overview of the different topologies and media types that support creating a backup set.




Lesson: Managing the Backup Process Upon completion of this lesson, you be able to:

Describe features and functions of common Backup/Recovery applications.

Describe the Backup/Recovery process management considerations.

Describe the importance of the information found in Backup Reports and in the Backup Catalog.

We have discussed the planning and operations of creating a Backup. Now, this lesson provides an overview of Management activities and applications that help manage the Backup and Recovery process.




How a Typical Backup Application WorksBackup clients are grouped and associated with a Backup schedule that determines when and which backup type will occur.

Groups are associated with Pools, which determine which backup media will be used.

Each backup media has a unique label.

Information about the backup is written to the Backup Catalog during and after it completes. The Catalog shows: – when the Backup was performed, and – which media was used (label).

Errors and other information is also written to a log.




Backup Application User Interfaces

There are typically two types of user interfaces:

Command Line Interface – CLI

Graphical User Interfaces – GUI




Managing the Backup and Restore Process

Running the B/R Application: Backup– The backup administrator configures it to be started, most (if not all)

of the times, automatically– Most backup products offer the ability for the backup client to initiate

their own backup (usually disabled)

Running the B/R Application: Restore– There is usually a separate GUI to manage the restore process– Information is pulled from the backup catalog when the user is

selecting the files to be restored– Once the selection is finished, the backup server starts reading from

the required backup media, and the files are sent to the backup client




Backup Reports

Backup products also offer reporting features.

These features rely on the backup catalog and log files.

Reports are meant to be easy to read and provide important information such as:– Amount of data backed up– Number of completed backups– Number of incomplete backups (failed)– Types of errors that may have occurred

Additional reports may be available, depending on the backup software product used.




Importance of the Backup CatalogAs you can see, backup operations strongly rely on the backup catalog

If the catalog is lost, the backup software alone has no means to determine where to find a specific file backed up two months ago, for example

It can be reconstructed, but this usually means that all of the backup media (i.e. tapes) have to be read

It’s a good practice to protect the catalog– By replicating the file system where it resides to a remote location– By backing it up

Some backup products have built-in mechanisms to protect their catalog (such as automatic backup)





The features and functions of common Backup/Recovery applications.

The Backup/Recovery process management considerations.

The importance of the information found in Backup Reports and in the Backup Catalog.

This lesson provided an overview of Backup and Recovery management activities and tools.




Module Summary

Key points covered in this module:

The best practices for planning Backup and Recovery.

The common media and types of data that are part of a Backup and Recovery strategy.

The common Backup and Recovery topologies.

The Backup and Recovery Process.

Management considerations for Backup and Recovery.

This lesson looked at Backup and Recovery. Backup and Recovery are a major part of the planning for Business Continuity.




Check Your Knowledge

What are three reasons for doing a Backup plan?

What are the three topologies that support creating a Backup set?

What are the advantages and disadvantages of using tape as the Backup media?

What are the three levels of granularity found in Backups?




Apply Your Knowledge…Upon completion of this topic, you will be able to:

Describe EMC’s product implementation of a Backup and Recovery solution.




Backupto disk

Disk-backup option

BasicTape backup and recovery

Advanced backupSnapshot

management

Remove riskFaster and more consistent data backup

Improve reliabilityKeep recovery copies fresh and reduce process errors

Lower total cost of ownershipCentralization and ease of use

Low SERVICE-LEVEL REQUIREMENTS High

Tiered Protection and Recovery ManagementEMC NetWorker

NetWorker’s installed base of more than 20,000 customers worldwide is a testament to the product’s market leadership.

Data-growth rates are accelerating, and the spectrum of data and systems that live in environments runs the gamut from key applications that are central to the business to other types of information that may be less important.

What is interesting is that the industry has been somewhat stuck for several years at a one-size-fits-all strategy to backup and recovery. We’re referring to a “basic” backup scenario, or traditional tape backup.

Tape backup serves a noble purpose and is working very well for some companies—it’s been EMC’s core business for some time, so EMC knows it well. But shifting market dynamics, as well as more demanding business environments, have lead to other important choices for backup.

Today, traditional tape faces the challenge of meeting service-level requirements for protection and availability of an ever-increasing quantity of enterprise data. This is why EMC has built into NetWorker key options to meet the needs of a wide range of environments. This includes the ability to use disk for backup, as well as to take advantage of advanced-backup capabilities that connect backup with array-based snapshot and replication management. These provide you with essentially the highest-possible performance levels for backup and recovery. As the value of information changes over time, you may choose any one of these, or a combination thereof, to meet your needs.




Enterprise protection– Critical applications– Heterogeneous platforms and

storage– Scalable architecture– 256-bit AES encryption and secure

authentication

Centralized management– Graphical user interface– Customizable reporting– Wizard-driven configuration

Performance– Data multiplexing– Advanced indexing– Efficient media management

Solution Features

Tape library

Basic ArchitectureHeterogeneous

clients

Backup server

Key applications

LAN

SANNAS

(NDMP)Storage

Node

NetWorker Backup and Recovery

The first key focus is on providing complete coverage. Enterprise protection means the ability to provide coverage for all the components in the environment. NetWorker provides data protection for the widest heterogeneous support of operating systems, and is integrated with leading databases and applications for complete data protection.

A single NetWorker server can be used to protect all clients and servers in the environment—or secondary servers can be employed, which EMC calls Storage Nodes, as a conduit for additional processing power or to protect large critical servers directly across a SAN without having to take data back over the network. Such LAN-free backup is standard with NetWorker.

NetWorker can easily back up environments in LAN, SAN, or WAN environments, with coverage for key storage such as NAS. As a matter of fact, NetWorker’s NAS-protection capabilities, leveraging the Network Data Management Protocol (NDMP), are unequaled.

The key here is that NetWorker can easily grow and scale as needed in the environment and provide advanced functionality, including clustering technologies, open-file protection and compatibility with tape hardware and the new class of virtual-tape and virtual-disk libraries.

While NetWorker encompasses all these pieces in the environment, EMC has made sure there is a common set of management tools.

With NetWorker, EMC has focused on what it takes within environments both large and small to get the best performance possible, in terms of both speed and reliability. This means the inclusion of capabilities such as multiplexing to protect data as quickly as possible while making use of the backup storage’s maximum bandwidth. It also means ensuring that the way in which EMC indexes and manages the saving of data is designed to provide not only the best performance, but also stability and reliability.




Critical Application and Database Protection

Offline (Cold)

Integration with application APIsfor backup and recovery

Backup without Application Modules

Backup with NetWorker Application Modules

Shut down application

Restart application

Back up application

Application

SAVE

Application

DO

WN

TIM

E

Application

Net

Wor

ker M

OD

ULE

24x7

OPE

RA

TIO

NS

Applications can be backed up either offline or online. NetWorker by itself can back up closed applications as flat files. During an offline, or cold, backup, the application is shut down, backed up and restarted after the backup is finished.

This is fine, but during the shutdown and backup period, the application will be unavailable. This is not acceptable in today’s business environments. This is why EMC has worked to integrateNetWorker with applications to provide online backup—specifically, with the use of NetWorker in conjunction with NetWorker Modules.

During an online, or hot, backup, the application is open and is backed up while open. The NetWorker Module extracts data for backup with an API; the application need not be shut down, and remains open while the backup finishes.

NetWorker supports a wide range of applications for online backup with granular-level recovery, including:

OracleMicrosoft ExchangeMicrosoft SQL ServerLotus NotesSybaseInformixIBM DB2EMC Documentum




NetWorkerUNIX/Linux

NetWorker Windows

Open Tape Format– Datastream multiplexing– Self-contained indexing– Cross-platform format

UNIX Windows Linux

– Minimize impact of tape corruption

Dynamic drive sharing– Cross-platform tape-drive sharing– On-demand device usage– Reduce hardware total cost of

ownership

Media-Management Advantages

One key advantage of NetWorker is its media-management features.

The first feature is Open Tape Format. It is NetWorker’s way of recording data to tape, specifically designed to provide several advantages:

Data can be multiplexed, or interleaved, for performance. This essentially means data can be accepted and written to the backup media as it comes in, regardless of what order it comes in, so the tape drives can keep spinning. This enables you to back up faster, but also reduces wear and tear on the tape hardware, which is more susceptible to error if it is continually stopping and starting.Tapes created by NetWorker are self-describing, so if everything else is gone except for the tape, you’ll be able to load it and understand what data is there to be restored.As the image on the right indicates, Open Tape Format allows you to move tape media between systems and servers on unlike operating systems—with Open Tape Format, a tape that began life on a UNIX-based system can easily be read on a Windows-based system. This is key not just for disaster recovery, but for the entire environment, as you go through a regular system lifecycle and adopt new platforms.Also, with Open Tape Format, NetWorker can skip bad spots on tape and continue data access. When other solutions on the market encounter any error on tape, they are unable to do anything further with the tape. Imagine if there is a bad spot 100 MB into a backup tape…Finally, NetWorker can broker tape devices on a SAN to get the best use and performance out of the hardware investment. So, instead of hard-assigning tape drives to a backup server or Storage Node, you can dynamically allocate any drive on demand.




Disk-backuptarget

NetWorker DiskBackup Option

High performance– Simultaneous-access operations– No penalty on restore versus tape

Policy-based migration of data from disk to tape

– Automated staging and cloning– Up to 50% faster– Clone backups jobs as they

complete– Reduce wear and tear on tape

drives and cartridges

Superior capability– Operational backup and recovery

for all clients, including NAS with NDMP

– Direct file access for fast recovery

Tape library

Backup-to-Disk Architecture

Heterogeneous clients

Backup server

Key applications

LAN

NAS Storage NodeSAN

The focus here is the resolution of the top pain points around traditional tape-based backup.

Performance—NetWorker backup to disk allows for simultaneous-access operations to a volume, both reads (restore, staging, cloning) and writes (backups). With NetWorker, as opposed to with traditional tape-only backup, you don’t "pay a penalty on restore."

Also, cloning from disk to tape is up to 50% faster. Why? As soon as the Save Set (backup job) is complete, the cloning process can begin without the Administrator having to wait for all the backup jobs to complete. NetWorker can back up to disk and clone to tape at the same time. You don’t have to spend 12–16 hours a day running clone operations (tape-to-tape copies)—in fact, you might actually be able to eliminate the clone jobs. Some NetWorker customers have seen cloning times reduced from 12–16 hours daily to three to four hours daily.

Cloning from disk to tape also augments the disaster-recovery strategy for tape. As data grows, more copies must be sent offsite. Because NetWorker backup to disk improves cloning performance, you can now continue to meet the daily service-level agreements to get tapes offsite to a vaulting provider.

Taking the idea of leveraging disk even idea further leads us into a discussion of to NetWorker’s advanced backup capability, which also leverages disk-based technologies.




Advanced Backup - Snapshots and CDP

Integration of backup with snapshots, full-volume mirrors, and Continuous Data Protection (CDP)

Instant restore

Off-host backups

Achieve stringent recovery-time objectives (RTOs), recovery-point objectives (RPOs)

It is expected that snapshot technology for data protection will surpass backup to tape as the trend in data protection as organizations continue to focus on recovery times

Productioninformation

Recover

Backup

Productionserver

Backupserver

Snapshot 11:00 a.m.

Snapshot 5:00 p.m.

Backup snap10:00 p.m.

Disk-solution providers, like EMC, provide array-based abilities to perform snapshots and replication. These “point-in-time” copies of data allow for instant recovery of disk and data volumes. Many are likely familiar with array-based replication or snapshot capabilities.

NetWorker is engineered to take advantage of these capabilities by providing direct tie-ins with EMC offerings such as CLARiiON with SnapView, or Symmetrix with TimeFinder/Snap. This will enable you to begin to meet the most stringent recovery requirements.

In a study done in the spring of 2004, the Taneja Group identified that the market intends to rely on snapshots for ensuring application-data availability and rapid recoveries. The figures represent a scale of one to five, with one as the low point, five as the high point:

Rapid application recovery (4.34)Ability to automate backup to tape (4.13)Instant backup (3.98)Roll back to point in time (3.88)Integration with backup strategy (3.87)Flexibility to leverage hardware (3.61)Multiple fulls throughout day (3.49)




Policy-based management– Administer snapshots in

NetWorker– Schedule, create, retain, and

delete snapshots by policy

Third-party integration– Leverage third-party replication

technologyArray-based (Symmetrix DMX, CLARiiON CX, etc.)Software-based (RecoverPoint)

Application recovery– Integration with Application

Modules to ensure consistent state

Exchange / SQL / Oracle / SAP

NetWorker PowerSnap Module

CLARiiON with

SnapViewTape library

Advanced BackupHeterogeneous

clients

Backup server

Key applications

LAN

SANNAS Storage

Node

In addition to traditional backup-and-recovery application modules for disk and tape, the snapshot management capability called NetWorker PowerSnap enables you to meet the demanding service-level agreement requirements in both tape and disk environments by seamlessly integrating snapshot technology and applications. NetWorker PowerSnap software works with NetWorker Modules to enable snapshot backups of applications—with consistency.

PowerSnap performs snapshot management by policy—just like standard backup policies to tape or disk. It uses these policies to determine how many snapshots to create, how long to retain the snapshots, when to do backups to tape from specified snapshots…all based on business needs that you define.

Note to Presenter: Click now in Slide Show mode for animation.

For example, snapshots might be taken every few hours, and the three most recent are retained. You can easily leverage any of those snapshots to back up to tape in an off-host fashion—i.e., with no impact to the application servers.

PowerSnap manages the full life cycle of snapshots, including creation, scheduling, backups, and expiration. This, along with its orchestration with applications, provides a comprehensive solution for complete application-data protection to help you meet the most stringent of RTOs and RPOs.




Block-level backups– Host-based snapshot– Targeted at high-density file

systems– Single-file restore– Sparse backups

High performance– Significant backup-and-restore

performance impact—up to 10 times faster

– Drive tape at rated speeds– Optional network-accelerated

serverless backup with Cisco intelligent switch

NetWorker SnapImage Module

1,000,000+ directories10,000,000+ files

Advanced Backup

If there are servers with lots of files and lots of directories—what we refer to as high-density file systems—backup and recovery are particularly challenging. With so many files, traditional backup struggles to keep up with backup windows.

NetWorker SnapImage enables block-level backup of these file systems while maintaining the ability to restore a single file. SnapImage is intelligent enough to also support sparse backups.

Sparse files contain data with portions of empty blocks, or “zeroes.”NetWorker backs up only the non-zero blocks, thereby reducing:− Time for backup −Amount of backup-media space consumed

Sparse-file examples:− Large database files with deleted data or unused database fields− Files from image applications

With the NetWorker SnapImage Module, backup and recovery of servers with high-density file systems is significantly increased:− The time required to back up 18.8 million 1 KB files in a 100 GB file system with a block

size of 4 KB can be reduced from 31 to seven hours.− The time required to perform a Save Set restore of one million 4 KB files in a 5.36 GB

internal disk can be reduced from 72 to seven minutes.




Solution Example: Major Telecom Company

Value PropositionZero backup window for applicationsEliminated data-loss riskReduced management overhead

Business Challenge:Complex application environmentNo backup window Recovery-time objective: Restore 24 TB in two hours

Enterprise-Information Protection

Solution:NetWorker PowerSnap with Symmetrix and TimeFinder/Snap

– Server-free backup

NetWorker DiskBackup Option with CLARiiON with ATA disks

– Rapid primary-site protection

NetWorker and SRDF/S– Disaster recovery– Offsite protection

55

Disaster-Recovery Site Production Site

SymmetrixDMX

Applicationhost

NetWorker

Storage Node PowerSnap

Disaster-recovery host

CLARiiONCX

SymmetrixDMX

Storage Node

Tapelibrary SAN

SAN Tapelibrary

SRDF/S

EMC has worked with a large Telecommunications company to meet their most demanding IT challenges:

Complex application environment—Oracle, and lots of dataNo backup window Recovery-time objective: Restore 24 TB in two hours.

They chose to implement NetWorker, along with other key EMC offerings, to achieve a superior level of protection and recovery management—and confidence in the ability to recover.

Solution:NetWorker PowerSnap with Symmetrix and TimeFinder/Snap− Server-free backup and rapid recovery

NetWorker DiskBackup with CLARiiON with ATA disks−Rapid primary-site protection and recovery

NetWorker and SRDF/S−Disaster recovery, offsite protection

Here is what they have been able to achieve with the above:Zero backup time for their applicationsZero data lossSignificantly reduced management overhead

Not all environments will be this complex or demanding, but NetWorker can meet any backup and recovery requirements, and can easily be upgraded to meet more stringent requirements as needed.

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