Backup Basics

7/28/2019 Backup Basics

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1010370-001

THE BASICBACKUP GUIDE

TAPEBACKUP STRATEGIESFORTHE

SMALL-TO-MEDIUM BUSINESS


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ii


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THE BASIC BACKUP GUIDE iii

Contents

About This Guide . . . . . . . . . . . . . . . . . . v

Why tape is ideal for backup....................... v

Tape automation - now available

for SMBs................................................. viWho should read this guide ....................... vi

1111 About Data Backup . . . . . . . . . . . . . . . 1

What does it mean to back up, restore,and archive?................................................. 1

What types of files should be backed up? .......... 1

How often should data be backed up?............... 2

When should backups take place? ..................... 3

How long should data be stored?....................... 3

Where should backup tapes be stored?.............. 4How often should tapes be retired? ................... 4


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iv THE BASIC BACKUP GUIDE

2222 Types of Backup . . . . . . . . . . . . . . . . . 5

Full backups ...................................................... 5

Partial backups .................................................. 6

Incremental backups................................... 6

Differential backups.................................... 7

Which backup strategy is best? .......................... 8

Time and tapes required for a backup......... 9

Tapes required for the restore process....... 10

3333 Tape Rotation . . . . . . . . . . . . . . . . . . 11

Six-tape rotation.............................................. 12

Grandfather - Father - Son (GFS)...................... 14

Tower of Hanoi ............................................... 16

Which rotation method is best? ....................... 18

4444 Tape Planning . . . . . . . . . . . . . . . . . . 19

Determining the number of required tapes...... 19

Determining the cost ....................................... 21

5555 Backup Tips. . . . . . . . . . . . . . . . . . . . 23

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . 25


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THE BASIC BACKUP GUIDE v

ABOUT THIS GUIDE

Suppose for a moment that a virus infects your entirecomputer network. The virus spreads through everyemployees workstation, into every document and databasefile. All your work, all your data its all destroyed. Howwould your business recover?

Without an adequate backup and recovery plan, yourbusiness is at risk. Because your company relies on its dataand mission-critical applications, the cost of downtime is

exorbitant, potentially exceeding thousands of dollars perhour for such expenses as recovering data and system files,replacing equipment, losing productivity, and losingcustomers. According to a recent disaster recovery study,nearly half of the companies that are unable to fully restoretheir data after a disaster will go out of business entirely.

WHYTAPEISIDEALFORBACKUP

Whether you are backing up an individual workstation or asmall network, tape is an ideal storage medium because it iscapable of storing high capacities of information for arelatively low cost. And, tape is perfect for archival because

you can store cartridges off-site for enhanced data security.


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vi THE BASIC BACKUP GUIDE

TAPEAUTOMATION - NOWAVAILABLEFOR SMBS

Until recently, tape backup for the small-to-mediumbusiness meant manually inserting tape cartridges into

individual tape drives. Tape automation has traditionallybeen the realm of big-budget IT departments. But now,affordable autoloaders and small tape libraries provideSMBs with the convenience and risk reduction previouslyavailable only to large businesses.

If you want to reduce the risk of human error in backups or

just dont want to spend time manually inserting andremoving tapes each time you back up, consider one oftodays automated tape solutions. A ten-cartridgeautoloader, such as Exabytes VXA-2 PacketLoader 1x10 1u,can provide reliable, unattended backup for up to twoweeks for little more than the price of a standalone tapedrive.

WHOSHOULDREADTHISGUIDE

Read this guide if you are responsible for protecting data ina small or medium business. It provides information abouthow to use tape technology for backup and recovery andhow to implement common backup strategies and taperotations.

NNNNOOOOTTTTEEEE:::: Whether you already have a tape backup system inplace or you are deciding to purchase a new tape backupsystem, you can find helpful advice in this guide.


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THE BASIC BACKUP GUIDE 1

1ABOUT DATABACKUP

This chapter addresses some common questions about databackup.

WHATDOESITMEANTOBACKUP, RESTORE,ANDARCHIVE?Data backup is the process of transferring data from yourcompanys primary computer system to a separate storagedevice, such as a tape drive. If the original data is lost ordamaged, you can restore the information from the deviceand resume normal business operations. An archive is a

long-term, permanent data backup, which is kept off-site.

WHATTYPESOFFILESSHOULDBEBACKEDUP?

The most important files to back up are data files the filesthat change on a frequent basis. Periodically, you should

also back up the entire system in case of a catastrophicdisaster. This periodic backup should include system filesthat contain specific user information for customizedsettings and passwords. You may also want to back upsoftware files if you no longer have the original disks. Mostbackup software provides the option of backing up all fileson the drive, the files that have changed since the lastbackup, or individually selected files.


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2 THE BASIC BACKUP GUIDE

HOWOFTENSHOULDDATABEBACKEDUP?

Because data files change every time someone enters newinformation, many companies back up the data files everyday (or only those files that have changed) and thenperform a complete backup of the entire system on aweekly, bi-weekly, or monthly basis. For your owncompany, you can determine the necessary frequency ofbackups by asking yourself how often the data changes andhow critical are the different types of data files. In other

words, how much data can you afford to lose withoutcausing your business undue hardship?

It may seem that you should back up your files almostcontinuously, but that isnt practical. The best strategy is todevise a schedule that works for the majority of your datafiles. For example, you can schedule a daily backup of new

and modified data files and then a weekly backup of allfiles. If you have critical files that must be backed up moreoften, you can back up these files throughout the day.

File typeBack up

dailyBack upweekly

Data files 4 4Critical files (may be backed upseveral times a day)

4 4

All other files (includes systemfiles and software files)

4


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WHENSHOULDBACKUPSTAKEPLACE?

Ideally, you should back up data after regular businesshours when employee demands on the network are at aminimum. This off-hours time frame is called the backupwindow. Many small companies have an adequate backupwindow to perform backup jobs at night and on weekends.

However, if your business operates 24 hours a day, 7 days aweek (24x7), or if you have employees working in different

time zones, you may have little or no backup window. Inthis case, you must determine a time period whenemployees will be the least affected.

TTTTIIIIPPPP:::: If your business operates 24x7, use backup software thathas an open file option. This option allows you to perform abackup while the files are in use.

HOWLONGSHOULDDATABESTORED?

How long you store data depends on the type of data andyour business requirements.

4For data files that change frequently, you should keeponly the most recent files. As the previous data becomesobsolete, you can overwrite and reuse the tapes.

4For the full set of files on your system, you should storethe files in a secure, off-site location. By having thiscomplete file set, you can recover the entire system in

case a disaster destroys the originals.

4For certain types of data (tax records, contracts, personnelfiles, patient records, and so on), you may need to archivedata for a specified time period to meet specific legalrequirements. In court cases, courts will hold owners andcompany officers liable for data loss (despite the reason

for the loss).


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WHERESHOULDBACKUPTAPESBESTORED?

You should store one full set of your companys data on-sitefor immediate recovery and another copy off-site at asecure location in case your business suffers a fire, theft, orother disaster. Many small companies choose to storebackup tapes in a safe-deposit box at a local bank or even atthe owner s home. To eliminate the hassle and worry, othercompanies prefer to contract with a vendor who specializesin archival and storage.

HOWOFTENSHOULDTAPESBERETIRED?

You should follow the tape manufacturers guidelines fortape storage and replacement. Most manufacturers printthese guidelines on the tape packaging. Also, most backup

software tracks errors on a given tape, which alerts you thata tape should be retired.

TTTTIIIIPPPP:::: If you still arent sure when to retire tapes, a good rule ofthumb is to retire tapes used for daily backups once a year.


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2TYPESOF BACKUPThis chapter describes the different types of backupstrategies, so you can decide which method is right for yourbusiness. Software applications include options for copyingthe full set of system files, for copying a partial set of new or

modified files, and for copying selected, individual files.Most companies use a combination of full and partialbackups by performing nightly backups on files that havechanged throughout the day, then a full backup of all fileson a weekend day.

FULLBACKUPS

Afull backup copies all the files on the system the systemfiles, the software files, and the data files. You shouldperform a full backup on a weekly, bi-weekly, or monthlybasis. With a full backup of your data set on tape, you canrestore your entire system if a disaster destroys the original

files.

TTTTIIIIPPPP:::: If your data set is small, you could perform a full backupon a daily basis. However, you should not use the same tapeevery day. Continuously overwriting a section of tape coulddamage it over a long period of time. (See Chapter 3 for moreinformation about effective tape rotation schemes.)


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PARTIALBACKUPS

A partial backup copies all files that have been added orchanged since the last backup job. There are two maintypes of partial backups: incremental and differential,summarized in the table below.

TTTTIIIIPPPP:::: For any crucial files that would be difficult to re-create,you can perform aselective backup at any time during the day.With this method, you dont need to wait until the nextscheduled backup to copy the crucial files.

INCREMENTALBACKUPS

If you need to save time and cost during regular backupjobs, choose a plan that includes full and incremental

backups. In this strategy, you perform a regular backup ofall files (weekly, bi-weekly, etc.), then a more frequentbackup (daily) of only the files that have changed since thelast backup session.

This full/incremental backup method means that fewer filesneed to be copied and less time is required for the backupprocedure. However, this method can also make a completesystem restore slower if you have created many differentincremental backup tapes (one for each day of the week, forexample), or if you need to restore only a particular file andmust hunt through several different incremental backuptapes. (See Which backup strategy is best? on page 8 for

more information.)

Backup type Files copied

Incremental Files added or changed since the lastfull orpartial

backup.Differential Files added or changed since the lastfull

backup.


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TTTTIIIIPPPP:::: Because an incremental backup session may only use asmall section of tape, you can conserve the required numberof backup tapes by using the softwares tape-append option.This option allows you to write additional backup sessions

where the previous session left off and to make full use of asingle tape. However, if you lose this one tape, youve lost datafrom several backup sessions.

DIFFERENTIALBACKUPS

If you need to save on restore time and hassle in the eventof a disaster, choose a plan that includes full and differentialbackups. In this strategy, you perform a regular backup ofall files (weekly, bi-weekly, etc.), then a more frequentbackup (daily) of all files that have changed since the lastfull backup session.

This full/differential backup method helps the restoreprocess run more efficiently, because only one full backuptape and one differential backup tape are required for acomplete restore of the system. However, this method isslower on the backup process because more files are copieddaily. (See Which backup strategy is best? on page 8 formore information.)

TTTTIIIIPPPP:::: If a full data backup requires more than one tape, youmight consider investing in a tape autoloader, which includes atape drive and a robotic arm that automatically handles taperotation. For a small price increase over a standalone tapedrive, an autoloader eliminates the need for manuallyswitching out tapes and eliminates the potential for humanerror.


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WHICHBACKUPSTRATEGYISBEST?

Is it better to combine full backups with incremental ordifferential partial backups? The answer for your situationdepends on what factors are most important to you. Do youwant to save time and cost on the backup process? If so, youshould choose incremental partial backups. Or, is it moreimportant to make the restore process as quick and simpleas possible in the event of a disaster? If so, you shouldchoose differential partial backups.

TTTTIIIIPPPP:::: Most companies perform full/differential backups,because the restore process only requires 2 tapes (or tape sets).

The table below highlights the main advantages anddisadvantages of incremental versus differential backupstrategies.

Backup type Advantages Disadvantages

Incremental(all new ormodified filessince lastfull or

partial backup)

Faster backup time becausethere are fewer files.

Reduced wear on backupdevice and tape.

Fewer tapes may be required.

Slower restore times becausethere may be more than twotapes required (the fullbackup tape and each

incremental backup tape). Higher cost of downtime in a

system disaster.

Differential(all new ormodified files

since lastfullbackup)

Faster restore times becausethere are only two tape setsrequired (the full and

differential backup tapes). Lower cost of downtime in a

system disaster.

Slower backup processbecause more files are copied.

Increased wear on backup

device and tape. More tapes may be required.


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TIMEANDTAPESREQUIREDFORABACKUP

The following examples show how a differential orincremental backup strategy affects the time and tapesrequired for backups.

For differential backups, the amount of data and hoursincrease throughout the week, requiring two more tapes

and almost twice the backup time than the incrementalbackup.

Differential backup: time and tapes required*

Day Type of backup Size Time No. of tapes

Friday Full 160 GB 4 hours 3 tapes

Monday Differential 45 GB 1.1 hours 1 tape

Tuesday Differential 56 GB 1.4 hours 1 tape

Wednesday Differential 67 GB 1.7 hours 2 tapes

Thursday Differential 83 GB 2.1 hours 2 tapes

Total: 411 GB 10.3 hours 9 tapes

Incremental backup: time and tapes required*

Day Type of backup Size Time No. of tapes

Friday Full 160 GB 4 hours 3 tapes

Monday Incremental 45 GB 1.1 hours 1 tape

Tuesday Incremental 11 GB .3 hours 1 tape

Wednesday Incremental 11 GB .3 hours 1 tape

Thursday Incremental 16 GB .4 hours 1 tape

Total: 243 GB 6.1 hours 7 tapes* These examples are based on a weekly backup cycle with a tape drive that can transfer data at 40 gigabytes

(GB) per hour on a 60-gigabyte capacity tape.


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TAPESREQUIREDFORTHERESTOREPROCESS

The following examples show how a differential or anincremental backup strategy affects the amount of tapesrequired for a restore process.

For a full system restore, the differential backup strategyrequires only Fridays full backup tape set and Thursdaysdifferential backup tape set, while the incremental backupstrategy requires all the backup tapes.

Differential backup: Tapes required for restore process

Day Type of backup Types of files copied

Friday Full Tape 1, 2, 3

Monday Differential Tape 4

Tuesday Differential Tape 5

Wednesday Differential Tape 6, 7

Thursday Differential Tape 8, 9

Tapes required for complete system restore: Tapes 1, 2, 3, 8, 9

Incremental backup: Tapes required for restore process

Day Type of backup Tapes required

Friday Full Tape 1, 2, 3

Monday Incremental Tape 4

Tuesday Incremental Tape 5

Wednesday Incremental Tape 6

Thursday Incremental Tape 7

Tapes required for complete system restore: All 7 tapes


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3TAPE ROTATIONThis chapter describes some common methods for taperotation, which determines when to reuse tapes during abackup cycle. A good rotation strategy protects data byensuring adequate file versions are always available on tape

and by protecting the tape from excessive wear anddamage, which could lead to unrecoverable data.

Most small companies use one of these rotation schedules:six-tape rotation, Grandfather - Father - Son (GFS), or Towerof Hanoi, described in more detail in the following sections.

NNNNOOOOTTTTEEEE:::: This chapter provides somesuggestions for how toimplement these rotation strategies. You can modify thestrategies in many different ways to fit your needs.


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SIX-TAPEROTATION

The six-tape rotation method is a simple and cost-effectivetape-a-day scheme, which is ideal for a small business

that does not need to back up high volumes of data. Thisrotation method involves rotating between two tapes forfull backups on Fridays, and then using four tapes for eitherincremental or differential backups on Monday throughThursday.

TTTTIIIIPPPP:::: If the full data capacity doesnt fit onto one tape, usetape sets. Most software provides options for tracking andmanaging tape sets.

To perform a six-tape rotation method:

1.1.1.1. Purchase six tapes and label them:Tape 1: FRI1Tape 2: FRI2Tape 3: MONTape 4: TUESTape 5: WEDTape 6: THU

2.2.2.2.

Beginning on a Friday, perform a full backup on the FRI1tape. Store the FRI1 tape off site.

TTTTIIIIPPPP:::: For even greater data protection, create duplicateFRI1 tapes: one for on-site storage and one for off-sitestorage.

3.3.3.3.

On Monday, Tuesday, Wednesday, and Thursday,perform an incremental or differential backup on theappropriately labeled tape. Store these tapes at yourcompany site.

4.4.4.4. On the next Friday, perform a full backup on the FRI2tape. Store this tape off site; and if desired, also retrieve

the FRI1 tape for next Fridays full backup.


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5.5.5.5. Repeat step 3, reusing the Monday through Thursdaytapes.

6.6.6.6. On Fridays, perform full backups, alternating between

the FRI1 and FRI2 tapes. Be sure to store at least oneFriday tape off site.

The chart below shows how you might create a six-taperotation schedule in a month.

Figure 3-1 Six-tape rotation method in a one-month period

TTTTIIIIPPPP:::: For an even more efficient and cost-effective type ofbackup schedule, you can perform a three-tape rotation. First,perform a full backup on Tape 1, then alternate between

Tape 2 and Tape 3 for nightly, differential backups. You canperform full backups every 2 weeks, or whenever you feel itsnecessary. This three-tape rotation method is ideal if you havea small amount of data to back up and you need to savemoney on media costs. And, by performing differentialbackups, you only need two tapes for a full system restore.

Incremental or Differential

FRI 1

MON TUES WED THU FRI 2




Full

MON TUES WED THU FRI


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GRANDFATHER - FATHER - SON (GFS)

The most commonly used tape rotation schedule is calledGrandfather - Father - Son (GFS). This rotation scheme

operates on the same five-day work week principle as thesix-tape rotation method, except that you use more tapes(or tape sets) for backing up data daily (on the son tapes),weekly (on the father tapes), and monthly (on thegrandfather tapes). The monthly tapes can be archivedfor permanent storage or recycled on a quarterly or yearlybasis.

The following steps show how to perform a simple GFSrotation method using 20 tapes:

1.1.1.1. Obtain 20 tapes and label them as follows:

44 daily tapes (sons) labeled MON through THURS44 weekly tapes (fathers) labeled WEEK1 through

WEEK4412 monthly tapes (grandfathers) labeled with the month

and year

NNNNOOOOTTTTEEEE:::: If a full backup exceeds the capacity of one tape,

create tape sets.2.2.2.2. Beginning on a Friday, perform a full backup on the

WEEK1 tape. Store the Week tapes either on site oroff site.

3.3.3.3. Beginning on the following Monday, perform daily

differential or incremental backups on the MONthrough THURS tapes. Store the MON throughTHURS tapes on site.

4.4.4.4. On Friday, perform another full backup on the WEEK2tape.


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5.5.5.5. Continue with this rotation method until the lastbusiness day of the month. On the last business day (nomatter what the day of the week it is), perform a fullbackup on the first monthly (grandfather) tape. Label the

tape with the current date and store it off site.

The following chart shows how you might create a GFSrotation schedule.

Figure 3-2 GFS rotation method in a one-month period

Incremental or Differential Full

MON TUES WED THUWEEK

2

MONTH

1

WEEK

1


3


4

MON TUES WED THU



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TOWEROF HANOI

The Tower of Hanoi schedule is a secure and cost-effectivetape-rotation method, but its also complex. In Tower of

Hanoi, you perform a full backup on five tape sets: labeledA, B, C, D, E. Tape Set A is used every other backup session;Tape Set B is used every fourth backup session; Tape Set C isused every eight sessions; and so on. You could performthese backup sessions nightly, weekly, or at whateverintervals you determine.

The table below shows how the Tower of Hanoi rotationmethod alternates for each tape set:

Backup session Tape set used

1 A

2 B

3 A4 C

5 A

6 B

7 A

8 D

9 A

10 B

11 A

12 C

13 A

14 B

15 A

16 E


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To perform a Tower of Hanoi tape rotation:

1.1.1.1. Label five tapes (or tape sets): A, B, C, D, E.

2.2.2.2. For the first backup session, perform a full backup onTape Set A.

3.3.3.3. For the second backup session, perform a full backup onTape Set B.

4.4.4.4. Continue alternating the tape sets as shown in the

previous table.

5.5.5.5. Once youve reached Tape Set E on the sixteenth day,begin the pattern over again. Store Tape E off site.

TTTTIIIIPPPP:::: For archival, you can periodically retire the Tape Set Ebackup.

The following chart shows a month of backups in the Towerof Hanoi rotation schedule.

Figure 3-3 Tower of Hanoi method in a one-month period

A

Tape

B

Tape

DTape

E

Tape


A

Tape

A

Tape

C

Tape

BTape

BTape

BTape

B

Tape

BTape

ATape

ATape

ATape

ATape

ATape

A

Tape

A

Tape

ATape

ATape

CTape

C

Tape

Full


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WHICHROTATIONMETHODISBEST?

Rotationmethod

Advantages Disadvantages

Six-tape Requires only a few tapes,which provides an easy andcheap rotation method. Itsideal for small data volumes (asmuch capacity as one tape canhold).

Keeps only a weeks worth ofdata, unless you regularlyarchive the full-backup tapes.

Grandfather -Father - Son(GFS)

Provides the most secure dataprotection and implementsmonthly archival of tapes. Itsalso a simple method, whichmost software supports.

Requires more tapes, which canbecome expensive.

Tower of Hanoi Allows for easy full-systemrestores (no shuffling throughtapes with partial backups onthem). This is ideal for smallbusinesses that are concernedwith being able to do fullrestores. Also, its more costeffective than GFS (uses fewer

tapes).

Requires a difficult rotationstrategy, which is not asstraight-forward to implementas the other rotation methods.Unless your backup softwaresupports it, this method is toocomplex to track tape rotationmanually. Also requires a

time-consuming full backupevery session.


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4TAPE PLANNINGThis chapter provides some considerations for planning thetotal number of tapes your backup strategy requires and thetape costs associated with that strategy.

DETERMININGTHENUMBEROFREQUIREDTAPES

To help determine how many tapes you need, consider thefollowing:

4Full backup size. What is the size, in gigabytes, of a full

system backup? This amount should include data files,system files, and software files. When youve determinedthe total capacity, divide that number by the totalcapacity of each cartridge. For example, if the totalcapacity of your system is 600 gigabytes, and each tapeholds 60 gigabytes, you will need 10 tapes.

TTTTIIIIPPPP:::: Most tape drives and software applications provide adata compression feature to reduce the size of files. Bycompressing data, youll reduce the amount of tapesneeded.

4P ti l b k i E ti t th i i i b t f


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4Partial backup size. Estimate the size, in gigabytes, of anaverage partial (differential or incremental) backup. Thisamount includes the data files that change on a dailybasis. For example, if an average incremental backup is

60 gigabytes, and each tape holds 30 gigabytes, you needtwo tapes for every incremental backup.

TTTTIIIIPPPP:::: By using the softwares tape-append feature, you canappend incremental or differential backups sets at the endof a previous backup. This saves on tape usage.

4Tape rotation method and frequency of backups. Whattype of tape rotation method will you implement andhow many tapes will it require? (See Chapter 3 for howtape rotation methods affect the number of tapes youneed.) For example, in a GFS rotation scheme, if you need1 tape for 4 partial backups a week (1x4=4 tapes), 3 tapesfor 4 weekly full backups (3x4=12 tapes), and 3 tapes for

12 monthly full backups (3x12=36 tapes), you wouldneed 52 tapes (4+12+36).

4Tape archival. How many tapes will you archive off-siteon a yearly basis? Will you archive one full backupmonthly or quarterly? For example, if a full backuprequires 3 tapes and you plan to archive a copy of one full

backup per month, youll need to purchase 36 tapes ayear for archival.

4Tape retirement. How often will you retire the tapes usedfor daily backups? You should determine a schedule forretirement, based on the tapes rated service live.

TTTTIIIIPPPP:::: If your software tracks rewrite errors, you may want tomonitor that number and discard any tape that shows asignificant increase in errors. The cost of replacing a tape ismuch lower than the cost of losing data.

DETERMINING THE COST


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DETERMININGTHECOST

You can purchase tapes in various lengths, which offervarious data capacities. Prices for tape cartridges can range

from $60 to $100 per tape, depending on the type of tapedrive you have. Youll also need to purchase a few cleaningcartridges to ensure proper tape drive operation.

TTTTIIIIPPPP:::: To help estimate your own tape requirements and cost,contact an Exabyte Sales representative.

Notes


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Notes


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5BACKUP TIPS

Finally, here are some additional tips for securing data:

4

Perform backups without exception. If your employeesare responsible for backing up their own data and you areconcerned that backups dont always happen, centralizethe backups across a network. To make backups easier,you can use backup software that performs the processautomatically. You can also invest in a tape autoloader,which will eliminate the need for a person to insert and

remove tapes.

4 After performing a backup, use the backup software toverify that the backup completed successfully. If yoursoftware does not contain this feature, you can restore oneor two unimportant files to be sure that the backup isvalid.

4 Rotate tapes to preserve multiple copies of data. Dontre-use the same tape for backup every day. If that tape islost or destroyed, you must re-create the data file by file.Also, create alternate copies of your data in case a tape isdamaged.

4 Keep backup tapes both at your company site and at an


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4 eep backup tapes bot at you co pa y s te a d at aalternate location. In the event of a day-to-day disaster (afile gets accidentally deleted or a local hard drive dies),keep a set of backup tapes on site for quick recovery. In

the event of a major disaster that affects your companylocation (such as a fire or flood), keep a set of backup tapesoff site in a secure location so you can restore yourbusiness to normal operations.

4 Run a good antivirus software on your computer systemto prevent viruses from being transferred onto your

backup tapes.

4 Clearly label tape cartridges so you can quickly identifythe correct restore tape. Label each tape with the date ofbackup, type of drive used, and enough information togenerally identify the contents. For example: 2/27/04 -Exabyte VXA - Weekly Fully Backup of Personnel

Records.

4 Take proper care of the tapes. Store tapes according to therecommendations listed on the tape packaging. Do notexpose tapes to sources of contamination, like copiers andprinters that emit toner and paper dust.

4 Take proper care of the tape drive. Most drives requireperiodic cleaning with a separate cleaning cartridge.Follow the manufacturers cleaning recommendations.

4 Consider using an archive vendor for tape storage. Anarchive vendor can provide services ranging from securefacilities for tape storage to prepaid delivery of your tapes

in the event of a disaster.


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INDEX

A

archiving tapes 1, 20, 24

automation, tape vi

B

backup window 3

backupsdefinition of 1differential 6 to 7full 5incremental 6 to 7selective 6strategies for 8time required for partialbackups 9

tips for 23 to 24

C

cartridges

See tapescost of tapes 21

D

differential backupadvantages and disadvantages 8description 6 to 7tapes required for restore 10time and tapes required 9

Ffiles

how long to store 3how often to back up 2types to back up 1when to back up 3

full backups 5

G

GFS rotation 14 to 15 18

T

tape automation vi


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GFS rotation 14 to 15, 18

I

incremental backup

advantages and disadvantages 8description 6 to 7tapes required for restore 10time and tapes required 9

Mmedia

Seetapes

P

partial backups 6 to 7

R

restoring data 1, 10

retiring tapes 4, 20

rotation methods 11 to 18

S

selective backups 6

six-tape rotation 12 to 13, 18

storing data 3storing tapes 4,24

strategies for backup 8

tape automation vi

tape-append feature 7,20

tapes

archiving 24autoloaders for 7cost 21determining how many to

purchase 19 to 20making full use of 7required for partial backups 9

retiring 4,20rotation methods 11 to 18storing 3, 4

Tower of Hanoi rotation 16 to 18

W

window, backup 3

COPYRIGHT Copyright 2002-2004 by Exabyte Corporation. All rights reserved.Thi i d h i f i i d h i h


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This item and the information contained herein are the propertyof Exabyte Corporation. No part of this document may bereproduced, transmitted, transcribed, stored in a retrieval system,or translated into any language or computer language in any formor by any means, electronic, mechanical, magnetic, optical,chemical, manual, or otherwise, without the express writtenpermission of Exabyte Corporation, 2108 55th Street, Boulder,Colorado 80301.

TRADEMARKNOTICES

Exabyte, VXA, and VXAtape are registered trademarks of ExabyteCorporation. All other product names are trademarks or registered

trademarks of their respective owners.

PART NUMBERANDREVISION HISTORY

1010370-001

CONTACTINGEXABYTE

Exabyte Corporation2108 55th StreetBoulder, Colorado 80301

(303) 442-4333

www.exabyte.com

Revision Date Description

000 January 2002 Initial release.

001 February 2004 Minor updates.

Notes


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