Data Backup Unit 10

Table of Contents 10.1. Data Backup 10.2. Types of Backup 10.3. Backup Procedures 10.4. Types of Storage 10.5. Features of a Good Backup Strategy

Data Backup Overview

kTip: Backup Backup is the activity of copying files or databases so that they will be preserved in case of equipment failure or other catastrophe.

The retrieval of files you backed up is called restoring them. kTip: Restoring files The retrieval of files you backed up is called restoring them.

Purpose 0f Data Backup All electronic information considered of institutional value should be copied onto secure storage media on a regular basis (i.e., backed up), for disaster recovery and business resumption.

Purpose 0f Data Backup Backup provisions allow processes to be resumed in a reasonable amount of time with minimal loss of data.

10.2 Types of Data Backup

Takeaway from this topic Learn about full backups, incremental and differential backups, and newer types of backups like mirror and offsite backups. This will help in choosing the best data backup type for your organization's data.

10.2.1 Full Backup

Simply put, It is a full copy of your entire data set. Full backup Full backup is a method of backup where all the files and folders selected for the backup will be backed up. Simply put, It is a full copy of your entire data set.

Full Backup - Usage It is commonly used as an initial or first backup followed with subsequent incremental or differential backups. After several incremental or differential backups, it is common to start over with a fresh full backup again.

Full Backup - Usage Some also like to do full backups for all backup runs; typically for smaller folders or projects that do not occupy too much storage space.

Full backup - Advantages Restores are fast and easy to manage as the entire list of files and folders are in one backup set. Easy to maintain and restore different versions.

Full backup -Disadvantages Backups can take too much time as each file is backed up again every time the full backup is run.

Full backup -Disadvantages Consumes the most storage space compared to incremental and differential backups.

Full backup -Disadvantages The exact same files are be stored repeatedly resulting in inefficient use of storage.

10.2.2. Incremental Backups

Incremental backup Because full backups are so time consuming, incremental backups were introduced as a way of decreasing the amount of time that it takes to do a backup. Incremental backups only backup the data that has changed since the previous backup.

Incremental backup With incremental backups, one full backup is done first and subsequent backup runs are just the changed files and new files added since the last backup.

For example, suppose that you created a full backup on Monday, and used incremental backups for the rest of the week.

Tuesday's backup would only contain the data that has changed since Monday. Wednesday's backup would only contain the data that has changed since Tuesday. And so on...

Incremental backup - Advantages Much faster backups.

Incremental backup - Advantages Efficient use of storage space as files are not duplicated. Much less storage space is used compared to running full backups and even differential backups.

Incremental backup - Disadvantages Incremental backups can be time-consuming to restore.

Incremental backup - Disadvantages Restores are a little more complicated. All backup sets (first full backup and all incremental backups) are needed to perform a restore.

10.2.3

Differential backups(***clonezilla full pc backup) A differential backup is similar to an incremental backup in that it starts with a full backup, and subsequent backups only contain data that has changed.

Differential vs. Incremental Backup The difference is that while an incremental backup only includes the data that has changed since the previous backup, a differential backup contains all of the data that has changed since the last full backup.

Differential vs. Incremental Backup Suppose for example that you wanted to create a full backup on Monday and differential backups for the rest of the week.

Differential vs. Incremental Backup Tuesday's backup would contain all of the data that has changed since Monday. It would therefore be identical to an incremental backup at this point. On Wednesday, however, the differential backup would backup any data that had changed since Monday.

Differential backups - Advantages Much faster than full backups.

Differential backups - Advantages More efficient use of storage space than full backups since only files changed since the last full backup will be copied on each differential backup run.

Differential backups - Advantages Faster restores than incremental backups.

Differential backups - Disadvantages Differential backups are slower then incremental backups.

Differential backups - Disadvantages As time progresses, a differential backup storage can grow to contain much more data than an incremental backup. In such a case, the storage may not be sufficient.

Differential backups - Disadvantages Restores are slower than with full backups.

Differential backups - Disadvantages Restores are also more complicated than full backups but simpler than incremental backups. Only the full backup set and the last differential backup are needed to perform a restore.

10.2.4. Mirror backups

Mirror backups A mirror backup is a straight copy of the selected folders and files at a given instant in time.

Mirror backups Mirror backup is the fastest backup method because it copies files and folders to the destination without any compression.

However, there’s a catch.

Because of this, mirror backups should be used with caution. With mirror backups, when a file in the source is deleted, the file is eventually also deleted in the mirror backup. Because of this, mirror backups should be used with caution.

30 day delete To tackle an issue like the files being deleted, many online backup services offer a mirror backup with a 30 day delete.

30 day delete This means that even when you delete a file on your source, that file is kept on the storage server for at least 30 days before it is eventually deleted.

What’s the point of this 30 day delete?

The functionality is similar to the Google Drive offline sync option. 30 day delete 30 day delete helps strike a balance offering a level of safety while not allowing the backups to keep growing since online storage can be relatively expensive. The functionality is similar to the Google Drive offline sync option.

Mirror backups - Advantages The backup is clean and does not contain old and obsolete files.

Mirror backups - Disadvantages There is a chance that files in the source get deleted accidentally, by sabotage or through a virus may also be deleted from the backup mirror.

10.2.5 Full Pc Backup

Full PC backup Full PC backup of full computer backup typically involves backing up entire images of the computer’s hard drives rather than individual files and folders.

Full PC backups are sometimes called “Drive Image Backups”. The drive image is like a snapshot of the drive. It may be stored compressed or uncompressed. Full PC backups are sometimes called “Drive Image Backups”.

Disadvantage with other backups With other file backups, only the users’ document, pictures, videos and music files can be restored while the operating system, programs etc. needs to be reinstalled from the source or disc media.

Advantage as compared to other backups With the full PC backup, we can restore the hard drives to their exact state when the backup was done.

Advantage as compared to other backups In other words, a full PC backup can restore a crashed computer to its exact state at the time the backup was made.

Full PC backup - Advantages A crashed computer can be restored in minutes with all programs databases emails etc intact. No need to install the operating system, programs and perform settings etc. Ideal backup solution for a hard drive failure.

Full PC backup - Disadvantages May not be able to restore on a completely new computer with a different motherboard, CPU, display adapters, sound card etc.

Full PC backup - Disadvantages Any problems that were present on the computer (like viruses, or mis-configured drivers, unused programs etc.) at the time of the backup may still be present after a full restore.

10.2.6 Local Backup

Local backup A local backup is any backup where the storage medium is kept close at hand.

Local backup Typically, the storage medium is plugged in directly to the source computer being backed up or is connected through a local area network to the source being backed up.

Local backup - Advantages Very fast backup and very fast restore.

Local backup - Advantages Offers good protection from internal hard drive failures, virus attacks, accidental deletes and deliberate employee sabotage on the source data.

Local backup - Advantages Storage cost can be very cheap when the right storage medium is used like external hard drives. Data transfer cost to the storage medium can be negligible or very cheap.

Local backup - Advantages Since the backups are stored close by, they are very conveniently obtained whenever needed for backups and restore.

Local backup - Advantages Full internal control over the backup storage media and the security of the data on it. There is no need to entrust the storage media to third parties.

Local backup - Disadvantages Since the backup is stored close by to the source, it does not offer good protections against theft, fire, flood, earthquakes and other natural disasters.

Local backup - Disadvantages When the source is damaged by any of these circumstances, there’s a good chance the backup will be also damaged.

10.2.7 Offsite Backup

is known as an offsite backup. Any backup where the storage medium is kept at a different geographical location from the source is known as an offsite backup.

Offsite Backup The backup may be done locally at first on the usual storage devices but once the storage medium is brought to another location, it becomes an offsite backup.

Offsite backup - Advantages Offers additional protection when compared to local backup such as protection from theft, fire, flood, earthquakes, hurricanes and more.

Offsite backup - Disadvantages Except for online backups, it requires more due diligence to bring the storage media to the offsite location.

Offsite backup - Disadvantages Because of increased handling of the storage devices, the risk of damaging the delicate storage devices is higher.

10.2.8. Online Backup

Online backup An online backup is a backup done on an ongoing basis to a storage medium that is always connected to the source being backed up.

Online backup Typically the storage medium or facility is located offsite and connected to the backup source by a network or Internet connection.

How does this work?

Step 1 Typically a client application is installed on the source computer being backed up.

Step 2 Users can define what folders and files they want to backup and at one times of the day they want the backups to run.

Step 3 The data may be compressed and encrypted before being sent over the Internet to the storage data center.

kTip: Storage facility The storage facility is a commercial data center located away from the source computers being backed up. Typically they are built to certain fire and earthquake safety specifications.

Backed up files are secure The files have higher security standards with CCTV and round the clock monitoring. They typically have backup generators to deal with grid power outages and the facility is temperature controlled.

Backed up files are secure Data is not just stored in one physical media but replicated across several devices.

Backed up files are secure These facilities are usually serviced by multiple redundant Internet connections so there is no single point of failure to bring the service down.

Online backup - Advantages Offers the best protection against fires, theft and natural disasters.

Online backup - Advantages Because data is replicated across several storage media, the risk of data loss from hardware failure is very low.

Online backup - Advantages Because backups are frequent or continuous, data loss is very minimal compared to other backups that are run less frequently.

Online Backup - Advantages Because it is online, it requires little human or manual interaction after it is setup.

Online backup - Disadvantages Is a more expensive option than local backups.

Online backup - Disadvantages Initial or first backups can be a slow process spanning a few days or weeks depending on Internet connection speed and the amount of data backed up.

10.2.9 Remote Backup

or other physical location. Remote backup Remote backups are a form of offsite backup with a difference being that you can access, restore or administer the backups while located at your source location or other physical location.

When is it not a remote backup? Putting your backup hard drive at your bank safe deposit box would not be considered a remote backup. You cannot administer or access it without making a trip to the bank.

The term “remote backup” is often used loosely and interchangeably with “online backup” and “cloud backup”.

Remote backup - Advantages Much better protection from natural disasters than local backups.

Remote backup - Advantages Easier administration as it does not need a physical trip to the offsite backup location.

Remote backup - Disadvantages More expensive than local backups. Can take longer to backup and restore than local backups.

10.2.10 Cloud Backup

Cloud backup Cloud backup is a term often used loosely and interchangeably with Online Backup and Remote Backup.

Cloud backup This is a type of backup where data is backed up to a storage server or facility connected to the source via the Internet.

Secure access With the proper login credentials, that backup can then be accessed securely from any other computer with an Internet connection. The term “cloud” refers to the backup storage facility being accessible from the Internet.

Cloud backup - Advantages Since this is an offsite backup, it offers protection from fire, floods, earthquakes and other natural disasters.

Cloud backup - Advantages Able to easily connect and access the backup with just an Internet connection.

Cloud backup - Advantages Data is replicated across several storage devices and usually serviced by multiple internet connections so the system is not at the mercy of a single point of failure.

Cloud backup - Advantages When the service is provided by a good commercial data center, service is managed and protection is unparalleled.

Cloud backup - Disadvantages a. More expensive than local backups. b. Can take longer to backup and restore.

10.2.11 FTP Backup

the backup is done via the File Transfer Protocol (FTP) FTP Backup This is a kind of backup where the backup is done via the File Transfer Protocol (FTP) over the Internet to an FTP Server.

Where FTP is located ? Typically the FTP Server is located in a commercial data center away from the source data being backed up. As the FTP server is located at a different location, this can be considered as another form of offsite backup.

FTP Backup - Advantages Since this is an offsite backup, it offers protection from fire, floods, earthquakes and other natural disasters.

FTP Backup - Advantages Able to easily connect and access the backup with just an Internet connection.

FTP Backup - Disadvantages More expensive than local backups.

FTP Backup - Disadvantages Can take longer to backup and restore. Backup and restore times are dependent to the Internet connection.

10.3 Backup Procedures

The simplest way to remember how to backup your images safely is to 10.3.1. The 3-2-1 rule The simplest way to remember how to backup your images safely is to use the 3-2-1 rule. We recommend keeping 3 copies of any important file (a primary and two backups).

to protect against different types of hazards.* 10.3.1. The 3-2-1 rule We recommend having the files on 2 different media types (such as hard drive and optical media), to protect against different types of hazards.*

1 copy should be stored offsite (or at least offline). 10.3.1. The 3-2-1 rule 1 copy should be stored offsite (or at least offline).

Let’s look at the types of local data backup procedures.

10.3.2 Data Backup Retention Retention of backup data must meet system and institution requirements for critical data.

kTip: Data Information collected, stored, transferred or reported for any purpose, whether in computers or in manual files. Data can include: financial transactions, lists, identifying information about people, projects or processes, and information in the form of reports.

kTip: Critical Data Data that needs to be preserved in support of the institution's ability to recover from a disaster or to ensure business continuity.

10.3.3. Testing Restoration of backup data must be performed in testing and validation on all types of media in use periodically.

10.3.4 Media Replacement Backup media should be replaced according to manufacturer recommendations.

10.2.5. Recovery Time The recovery time objective (RTO) must be defined and support business requirements.

kTip: Recovery Point Objective (RPO) Acceptable amount of service or data loss measured in time. The RPO is the point in time prior to service or data loss that service or data will be recovered to.

kTip: Recovery Time Objective (RTO) Acceptable duration from the time of service or data loss to the time of restoration.

10.3.6. Roles and Responsibilities Appropriate roles and responsibilities must be defined for data backup and restoration to ensure timeliness and accountability.

10.3.7. Offsite Storage Removable backup media taken off site must be stored in an offsite location that is insured and bonded or in a locked media rated, fire safe.

kTip: Media Rated, Fire Safe A safe designed to maintain internal temperature and humidity levels low enough to prevent damage to CDs, tapes, and other computer storage devices in a fire. Safes are rated based on the length of time the contents of a safe are preserved while directly exposed to fire and high temperatures.

10.3.8. Onsite Storage Removable backup media kept on site must be stored in a locked container with restricted physical access.

10.3.9. Media Destruction Media Destrucation speaks of how to dispose of data storage media in various situations.

Information cannot be restored in any form following destruction. kTip: Destruction Destruction of media includes: disintegration, incineration, pulverizing, shredding, and melting. Information cannot be restored in any form following destruction.

10.3.10. Encryption Non-public data stored on removable backup media must be encrypted in transit and at rest when sent to an offsite backup facility, either physically or via electronic transmission.

10.3.11. Third Parties Third parties' backup handling & storage procedures must meet system, or institution policy or procedure requirements related to data protection, security and privacy.

10.3.11. Third Parties These procedures must cover contract terms that include bonding, insurance, disaster recovery planning and requirements for storage facilities with appropriate environmental controls.

10.4 Types of storage

Types of storage Generally, storage types are classified into the following. Local storage options Remote storage options

In this module, we will focus on Local Storage options.

10.4.1. External Hard Drive These are hard drives similar to the type that is installed within a desktop computer or laptop computer.

10.4.1. External Hard Drive The difference being that they can be plugged into the computer or removed and kept separate from the main computer.

External Hard Drive - Advantages Very good option for local backups of large amounts of data.

External Hard Drive - Advantages The cheapest storage option in terms of cost per GB. Very reliable when handled with care.

External Hard Drive - Disadvantages Can be very delicate. May be damaged if dropped or through electrical surge.

Internally, they are completely different. 10.4.2. Solid State Drive Solid State Drives look and function similar to traditional mechanical/ magnetic hard drives but the similarities stop there. Internally, they are completely different.

Solid State Drives have no moving parts or rotating platters. They rely solely on semiconductors and electronics for data storage making it a more reliable and robust than traditional magnetic drives.

10.4.2. Solid State Drive No moving parts also means that they use less power than traditional hard drives and are much faster too.

Solid State Drive - Advantages Faster read and write performance.

Solid State Drive - Advantages More robust and reliable than traditional magnetic hard drives.

Solid State Drive - Advantages Highly portable. Can be easily taken off site.

Solid State Drive - Disadvantages Relatively expensive when compared to traditional hard drives.

Solid State Drive - Disadvantages Storage space is typically less than that of traditional magnetic hard drives at the same price bracket.

10.4.3. Network Attached Storage (NAS) NAS are simply one or more regular IDE or SATA hard drives plugged in an array storage enclosure and connected to a network Router or Hub through a Ethernet port.

10.4.3. Network Attached Storage (NAS) Some of these NAS enclosures have ventilating fans to protect the hard drives from overheating.

NAS - Advantages Very good option for local backups especially for networks and small businesses. As several hard drives can be plugged in, NAS can hold very large amounts of data.

which increases the reliability and the read and write performance. NAS - Advantages Can be setup with redundancy (RAID - redundant array of inexpensive disks) which increases the reliability and the read and write performance.

NAS - Advantages Depending on the type of RAID level used, the NAS can still function even if one hard drive in the RAID set fails. Or two hard drives can be setup to double the read and write speed of single hard drive.

NAS - Advantages The drive is always connected and available to the network making the NAS a good option for implementing automated scheduled backups.

Significantly more expensive than using single external hard drives. NAS - Disadvantages Significantly more expensive than using single external hard drives.

Difficult to bring off site. NAS - Disadvantages Difficult to bring off site. Very much a local backup; and hence, still susceptible to some events like theft and floods, fire etc.

10.4.4. USB Thumb Drive or Flash Drive USB Thumb Drives or Flash drives are similar to Solid State Drives except that these are much smaller in size and capacity. They have no moving parts. This makes them quite robust.

10.4.4. USB Thumb Drive or Flash Drive They are extremely portable and can fit on a keychain. They are ideal for backing up a small amount of data that need to be brought with you on the go.

Much more robust than traditional magnetic hard drives. Advantages The most portable storage option. Can fit on a keychain making it an offsite backup when you bring it with you. Much more robust than traditional magnetic hard drives.

Disadvantages Relatively expensive per GB so can only be used for backing up a small amount of data.

10.4.5. Optical Drive(CD/DVD) CDs and DVDs are ideal for storing a list of songs, movies, media or software for distribution or for giving to a friend due to the very low cost per disk.

10.4.5. Optical Drive(CD/DVD) They do not make good storage options for backups due to their shorter lifespan, small storage space and slower read and write speeds.

Advantages Low cost per disk.

Relatively shorter lifespan than other storage options. Disadvantages Relatively shorter lifespan than other storage options.

Disadvantages Not as reliable as other storage options like external hard disk and SSD. One damaged disk in a backup set can make the whole backup unusable.

10.4.6. Cloud storage Cloud storage is storage space on commercial data center accessible from any computer with Internet access. It is usually provided by a service provider and is a remote storage option.

Cloud: Limited storage space A limited storage space may be provided free with more space available for a subscription fee. Examples of service providers are Amazon S3, Google Drive, SkyDrive etc.

Cloud Storage - Advantages A very good offsite backup. Not affected by events and disasters such as theft, floods, fire etc.

Cloud Storage - Disadvantages More expensive than traditional external hard drives. Often requires an ongoing subscription.

Cloud Storage - Disadvantages Requires an Internet connection to access the cloud storage.

10.5 Features of a Good Backup Strategy

10.5.1. Features to aim The following are features to aim for when designing your backup strategy. 1. Able to recover from data loss in all circumstances like hard drive failure, virus attacks, theft, accidental deletes or data entry errors, sabotage, fire, flood, earthquakes and other natural disasters.

10.5.1. Features to aim 2. Able to recover to an earlier state if necessary like due to data entry errors or accidental deletes.

10.5.1. Features to aim 3. Able to recover as quickly as possible with minimum effort, cost and data loss.

Hence able to run automated or semi-automated. 10.5.1. Features to aim 4. Require minimum ongoing human interaction and maintenance after the initial setup. Hence able to run automated or semi-automated.

10.5.2. Planning Your Backup Strategy Planning backup strategies include What to Backup? Where to Backup to? When to Backup? Backup types Compression & Encryption Testing your Backup Backup Utilities & Services

What to Backup? In planning your backup strategy, the first step is to identify what needs to be backed up.

1. Identify the files and folders that you cannot afford to lose. What to Backup? 1. Identify the files and folders that you cannot afford to lose.

What to Backup? It involves going through your documents, databases, pictures, videos, music and program setup or installation files.

Pictures and videos may be irreplaceable. What to Backup? Pictures and videos may be irreplaceable.

These are the files and folders that need to be in your backup plan. What to Backup? Other files like documents and databases may be tedious or costly to recover from hard copies. These are the files and folders that need to be in your backup plan.

Now that we have a clear idea of what to backup, let’s look at where to store them.

Let’s learn more about them. 2. Where to Backup to? In light of some content being irreplaceable, the backup strategy should protect against all events. Hence a good backup strategy should employ a combination of local and offsite backups. Let’s learn more about them.

Local backups Local backups are needed due to their lower cost allowing you to backup a huge amount of data.

Local backups Local backups are also useful for their very fast restore speed allowing you to get back online in minimal time.

Offsite backups Offsite backups are needed for the wider scope of protection against major disasters or catastrophes not covered by local backups.

3. When to Backup? How often you backup your data is the next major consideration when planning your backup policy.

Deciding the frequency of the backup. Some folders are fairly static and do not need to be backed up very often. Other folders are frequently updated and should correspondingly have a higher backup frequency like once a day or more.

Deciding the frequency of the backup. Your decision regarding backup frequency should be based on a worst case scenario.

Deciding the frequency of the backup. For example, if tragedy struck just before the next backup was scheduled to run, how much data would you lose since the last backup?

Deciding the frequency of the backup. How long would it take and how much would it cost to recollect that lost data?

Backup Start Time You would typically want to run your backups when there’s minimal usage on the computers.

Also, files that are open or in use may not get backed up. Backup Start Time Backups may consume some computer resources that may affect performance. Also, files that are open or in use may not get backed up.

Scheduling backups Scheduling backups to run after business hours is a good practice provided that the computer is left on overnight.

Scheduling backups Backups will not normally run when the computer is in “sleep” or “hibernate mode”.

Scheduling backups Some backup software will run immediately upon boot up if it missed a scheduled backup the previous night.

Now for one of the prime questions, When to schedule a backup?

When to schedule a backup? For example, if the first hour on a business day morning is your busiest time, you would not want your computer doing its backups then.

When to schedule a backup? If you always shut down or put your computer in sleep or hibernate mode at the end of a work day, maybe your lunch time would be a better time to schedule a backup.

When to schedule a backup? Just leave the computer on but logged-off when you go out for lunch.

Server Backups Since servers are usually left running 24 hours, overnight backups for servers are a good choice.

Each backup type has its own advantages and disadvantages. 4. Backup Types Many backup softwares offer several backup types, which include Full Backup, Incremental Backup and Differential backup. Each backup type has its own advantages and disadvantages.

Advantage with a full backup. Full backups are useful for projects, databases or small websites where many different files (text, pictures, videos etc.) are needed to make up the entire project and you may want to keep different versions of the project.

5. Compression & Encryption As part of your backup plan, you also need to decide if you want to apply any compression to your backups.

5. Compression & Encryption For example, when backing up to an online service, you may want to apply compression to save on storage cost and upload bandwidth.

Compression You may also want to apply compression when backing up to storage devices with limited space like USB thumb drives.

Compression If you are backing up very private or sensitive data to an offsite service, some backup tools and services also offer support for encryption.

Encryption Encryption is a good way to protect your content should it fall into malicious hands.

Encryption When applying encryption, always ensure that you remember your encryption key.

Encryption You will not be able to restore it without your encryption key or phrase.

6. Testing your backup A backup is only worth doing if it can be restored when you need it most. It is advisable to periodically test your backup by attempting to restore it.

Some backup utilities offer a validation option for your backups. Testing your backup Some backup utilities offer a validation option for your backups. While this is a welcome feature, it is still a good idea to test your backup with an actual restore once in awhile.

7. Backup Utilities & Services Simply copying and pasting files and folders to another drive would be considered a backup.

7. Backup Utilities & Services However the aim of a good backup plan is to set it up once and leave it to run on its own.

7. Backup Utilities & Services You would check up on it occasionally but the backup strategy should not depend on your ongoing interaction for it to continue backing up.

A good backup plan would incorporate the use of good quality, proven backup software utilities and backup services.

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