1. 2.6 Backup and Recovery

2.  Print out Scary backup stories

3. 1. What 6 questions should you ask yourself before writing a backup
strategy?
2. When devising a backup strategy, risk assessment should be carried
out, what should be looked at during this process?
3. What effect would it have on an organisation if they lost their data?
4. What 4 types of backup can be performed?
5. Describe a Full backup
6. Describe a differential backup
7. Describe an incremental backup
8. In order to make sure backups work what should you do?
9. What types of media could be used to backup systems?
10. What is meant by continuity of service and why is it important?
11. What is RAID
12. What is DRP and what does it aim to do?
13. What is backup strategy?
14. When choosing backup media and devices what factors should be
taken into consideration?

5.  Do you backup your work?
 What work do you backup?
 When do you back it up?
 How do you backup your work?
 Which media do you use to backup your work?
 Why do you back up your work?
 Different individuals and organisations have
different backup needs but they will all ask the
same questions
 http://ictknowledgebase.org.uk/backupstrategy

6.  Read and discuss the stories
 What 3 things must you do in order for
backups to work?
◦ Define and implement a good procedure
◦ Test that it works
◦ Review your procedure often

7.  I asked you these questions:
◦ What work do you backup?
◦ When do you back it up?
◦ How do you backup your work?
◦ Which media do you use to backup your work?
 Organisations will also need to ask these two questions:
◦ Who will be responsible for the backup
◦ Where will the data be stored
 Establishing the answers to these questions will allow
the organisation to develop a Backup Strategy*

8. 1. Assess what risks apply to the data
2. How likely it is that the hazards creating
those risks will take place
3. What effect would it have on the
organisation if that hazard occurred?
 For some organisations their ICT systems is
mission critical (They cannot operate without it)
 If EasyJet‟s booking system went down for
more than 48hrs they would go bankrupt

9. Natural Disasters Causes of Lost Data
2%
Human Error
6%
13%
32%
Software Corruption
Virus Attack
22%
Hardware Error 25%
Sabotage

10.  Must conduct thorough analysis
 Must be monitored
◦ e.g. signing up for e-mails or alerts from local
weather stations so that you are made aware of
impending weather events

11.  Damage to reputation
 Damaged loyalty
◦ i.e. customers may defect to a competitor
 Loss of labour
 Loss of revenue
 Loss of service

12.  http://goo.gl/Nlxl5
 On average, businesses lose between $84,000
and $108,000 (US) for every hour of IT system
downtime, according to estimates from studies
and surveys performed by IT industry analyst
firms.
 It is critical that organisations can recover quickly
 *Discussed later on under „continuity of service‟

13.  A recent study has shown that of the
companies that lose their data in a disaster:
 29% are out of business within two years
 Nearly 43% never open their doors after the
disaster

16.  As you can see backing up data is important. Most
organisations will have a backup strategy in place to
support their data protection and recovery.
 A strategy is simply a plan of action designed to achieve
an overall aim
 A backup strategy therefore is a planned approach to data
protection and data recovery
 Policies/Procedures are written to support implementation
of the strategy
◦ A Policy/Procedure might be “a full backup must be performed
every night”

17. ◦ What work do you backup?
◦ When do you back it up?
◦How do you backup your work?
◦ Which media do you use to backup your work?
◦ Who will be responsible for the backup
◦ Where will the data be stored
 You have choices as to HOW you backup your work

18.  Full Backup
◦ All the data that is stored in your files or folders that you wish to
back up will be saved.
 Advantages
◦ EVERYTHING is backed up at once on one device
◦ Restoring the data can be a simple process
◦ Data can better protected
 Disadvantages
◦ Can take a long time to run the backup (depending on quantity of
data)
◦ Can take a long time to restore the back up
◦ Storage media and medium for a FULL backup could be expensive
◦ Security issue as each full backup contains an entire copy of all
data

19.  Differential Backup
◦ Only the data that is different since the last FULL backup
will be saved
 Advantages
◦ Reduces the time it takes to restore data
◦ Usually an automatic process
◦ Only the full and differential backup are needed to
restore the data
 Disadvantages
◦ If to many differential backups are performed size of the
backup can be larger than full backup
◦ Slower than an incremental backup

20.  Incremental Backup
◦ Saves all the files that have been changed since the
last backup (NOT just the last FULL backup)
 Advantages
◦ Fastest way to backup
◦ Usually an automatic process
 Disadvantages
◦ Restoring data can take a long time

21.  Full Backup
◦ All the data that is stored in your files or folders that you
wish to back up will be saved.
 Differential Backup
◦ Only the data that is different since the last FULL backup
will be saved
 Incremental Backup
◦ Saves all the files that have been changed since the last
backup (NOT just the last FULL backup)
 Here‟s a video to help illustrate the difference
between an incremental backup and a differential
backup: http://goo.gl/3hyG3

22.  Refers to backup of computer data by automatically saving a copy of
every change made to that data
 Essentially capturing every version of the data that the user saves.
 Advantages
◦ It allows the user or administrator to restore data to any point in time
◦ In some situations, continuous data protection will require less space on backup
media (usually disk) than traditional backup.
 Most continuous data protection solutions save byte or block-level differences rather
than file-level differences. This means that if you change one byte of a 100 GB file, only
the changed byte or block is backed up
 Disadvantages
◦ The continuous bandwidth usage can adversely affect network
performance, especially in operations where file sizes are large, such as multimedia
and CAD design environments.
 To mitigate this risk, companies employ throttling techniques which prioritize network
traffic in order to reduce the impact of backup on day-to-day operation

23.  Some solutions which are marketed as
continuous data protection may only allow
restores at fixed intervals such as 1 hour, or 24
hours.
 Such schemes are not universally recognized as
true continuous data protection, as they do not
provide the ability to restore to any point in time.
 Such solutions are often based on
periodical snapshots,

24.  There is a popular backup method called the
Grandfather, Father, Son backup
 Homework 1
◦ Research the Grandfather, Father, Son backup
method and create a resource to illustrate this
process
http://www.lockergnome.com/it/2005/04/18/gfs-backup-strategy/

25. ◦ What work do you backup?
◦ When do you back it up?
◦ How do you backup your work?
◦Which media do you use to backup your work?
◦ Who will be responsible for the backup
◦ Where will the data be stored
 You have choices as to WHICH media you backup
your work on

26.  Dependant on:
◦ Storage capacity required
◦ Portability of device
◦ Speed of data transfer
◦ Speed of access (time it takes for device to find a
specific piece of stored data

27.  Magnetic Tape
 Hard disks
 Optical disks e.g. CD, DVD
 Remote Backup service e.g. online backup
 Flash Memory
 Homework 2
◦ Create a PowerPoint presentation with 6 slides
◦ Slide 1 called Backup media
◦ Slide 2-6 titles are those above (e.g. Magnetic Tape)
◦ On slides 2-6 introduce the media (include a picture)
and then highlight advantages and disadvantages of
using that media e.g. cost storage capacity, speed etc.

28.  Have you ever had to recover your work?
 What procedures did you go through in order
to recover your work?
 Remember recovery (like backup) should be:
◦ Planned
◦ Checked i.e. checked people understand
◦ Tested i.e. checking the recovery

29.  Organisations need recovery procedures
 These procedures are put in place to get the
ICT system working again
 Procedures considered include:
◦ Alternative accommodation
◦ Availability of step to help recovery process
◦ Availability of hardware to run the backups
◦ Training
◦ Availability of alternative communication lines

30.  Many companies rely on 24/7 service in
order to function (e.g. online booking
systems).
 Failure to do so could have financial
consequences as well as customer
dissatisfaction.
 Policies are required to ensure this
happens, should cover:
◦ Location of backup
◦ Security of backup
◦ Appropriate backup for continuous service e.g.
RAID

31.  Redundant Array of Independent Disks
 RAID 1 – Mirroring
◦ Mirror the drives
◦ Exact copy
 RAID 5 – Distributed Parity
◦ Strips the data across all 5 drives
◦ Can survive on two drives

32.  Disaster Recovery Plan
 Tries to ensure that businesses can:
◦ Resume trading quickly by ensuring ICT services are
back online as soon as possible
◦ Give customer, investors and trading partners
confidence in the reliability of the company
◦ Retain customers who might change companies if
there is a loss in trading time

33.  Half the class
◦ Research the Grandfather, Father, Son backup method
and create a resource to illustrate this process
 Other half
◦ Create a PowerPoint presentation with 6 slides
◦ Slide 1 called Backup media
◦ Slide 2-6 titles are those above (e.g. Magnetic Tape)
◦ On slides 2-6 introduce the media (include a picture)
and then highlight advantages and disadvantages of
using that media e.g. cost storage capacity, speed etc

37.  Page 99 and 100 of the McNee and Spencer Text
Book.
 Read both Case Studies and answer the „End of
sub-Topic Questions‟ 4, 5 and 6 (Page 100)
 For tomorrow‟s lesson (This must be printed out
prior to lesson NOT on your arrival to the lesson)
◦ Thursday detention if failure to complete OR failure to
have printed out before the lesson