Backing up and archiving

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Backing up and Archiving Data
Chapter 1
Introduction
• This presentation covers the following:
– What is backing up
– What is archiving
– Why are both necessary?
Backing up
• Backing up data is a practice that all organisations and
people who work with data should do.
• Some people consider data to be a company’s most
important asset.
• The loss of any data can have a detrimental impact on
an individual or an organisation (no matter the size).
• Backing up data is simply making a copy of current
data.
Backing up
• There are many causes of data loss:
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Loss of power
Hardware failure
File corruption
Viruses
Hackers
Theft of equipment
Sabotage of an employee
Espionage by a rival company
Natural Disaster
Honest blunders!
Accidently misplacing data
Backing up
• Back ups can be used to restore lost files by
replacing them with a previously saved file.
• You might not always get the most up-to-date
file but consider the alternative...starting your
work from the beginning again!
Methods of backing up
• There are many devices which can be used to
back up files:
– External memory: Memory cards, USB pen drives
– External hard drive
– Tape
– Making an exact copy of a disk
Backing up
• In the event that you need to find a file which has
been backed up you need to be able to find the
file you need!
• This means that back ups need to be organised.
• If you have made several backups of a file you
need to be able to tell which is the most recent
backup!
Things to consider
• How often do you need to back up?
• How far should your backups go?
– Days
– Weeks
– Months
Archiving
• Archiving is for long-term storage of data that
is not required immediately.
• More often than not it is never required again
but it kept just in case.
• Data is often removed from a system and
stored separately.
Archiving
• Consider the following example:
• A school records data about pupils’ performance every
year. If they continued to collect data, even after pupils
had left school, the system resources would soon diminish.
• Instead, records about pupils are removed from the system
once they leave.
• However, some data may be archived such as average test
scores and achievement rates. The data is not needed
immediately but may be useful to keep for the future.
Archiving
• Schools often keep full records about pupils
for up to seven years.
• Schools often receive requests to complete
references and use the data in their archives
to compile them.
Archiving Procedure
• Copy the file onto the archival media.
• Verify the copied files (i.e. Making sure the
copies are the same).
• Delete the original records from the system.
Reasons for archiving
• Free up system resources
– Less hard disk space required
• Increase system performance
– Searches take less time as their is less data to
search through
– Takes less time to make backups of the system as
there is less to copy!
Take note:
• Using an example, define what is meant by the term ‘backup’.
• Using an example, define what is meant by the term
‘archive’.
• Why is it important to back up data?
• What is the difference between archiving and back-up of
data?
• What storage medium should be used for archiving?
Remember
Archiving is removing!
Backing up is copying!
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