Chapter 16 – Disaster Recovery and Business Continuity ppt

Backups concerns• Ensure all necessary data is backed up • Ensure documentation exists on backup and • Backups are the IT persons biggest “risk” It used to keep me up at night... Quest

All-In-One Edition Chapter 16 – Disaster Recovery

and Business Continuity

Some Types of Disasters (475)

Disaster Recovery Plan (476)

Disaster Recovery Planning deals with

trying to prepare for a disaster in order to minimize the effects and as such the

loss.

• Spells out the required actions and resources

necessary to restore mission critical processes.

• Ideally make the recovery process as transparent to users as possible

BIA* (477)

A BIA helps identify mission critical functions

(examples?) and the effect a disaster would have on those functions.

– Determine for each function the MTD/category of each

Contingency plan

• Who is responsible for each business function

• What individuals are needed

• What is the priority

• Responsibility checklist

• Emergency contacts

• Warning system

• Procedures

– Only partially configured

– Cannot really be used for DRP testing

Alternate sites (n/b)

Rather than having a “subscription service” the company may own it’s own redundant sites

• Mirror sites

• Multiple data processing sites

Backups

Backups (481)

Backups are a critical component in not only DRP but also “normal operation”

Full (481)

• All data everyday!

• Clear archive bit after

backups

Incremental (481)

• Only files that changed since last full

or last incr

• Reset the archive bit

Differential (481)

• Only files changed since last full

or diff

• DO NOT reset the archive bit

Backup storage

• Should be at Secure off-site location

– Bank vault

– Other organization location

– Secure storage company

• Additional set On site for quick access

– Why?

Backups concerns

• Ensure all necessary data is backed up

• Ensure documentation exists on backup and

• Backups are the IT persons biggest “risk” It used

to keep me up at night.

Questions (n/b)

• If I do a full backup every day, and I lose my data

on Wednesday morning What tapes would I need

to restore, what is the restoration order?

• If I do a full backup on Sunday and incremental

mon-sat, and my system is lost on Wednesday

morning, what tapes do I need to restore, what is

the restoration order? (problems with this?)

• If I do a full backup on Sunday and diffs on mon-sat, system lost on Wednesday morning, what tapes do

I need to restore, what is the restoration order.

• Can I mix incremental and differential backups?

One other type of backup (481)

There is a new type of backup, called a “delta”

or “continuous backup or transactional

backup” This is a very exciting idea

How it works

• For each file make sure you get a full copy when the file is created

• Anytime a file changes, copy ONLY the

changes that occurred Do this in real time if

Continuous Backups (481)

Advantages:

• Much less backup time/cost

• Point in time recovery!!!

• Real Time!

• No scheduled backups

Disadvantages

Redundancy and Fault Tolerance, Single Points of

Failure

Single Points of Failure (n/b)

When planning for a disaster its IMPERATIVE you determine what places are single points

of failure for your business process

Implement the solutions to make these high availability, using redundancy and fault

tolerant technology

Redundancy and Fault Tolerance

Both of these terms are essential to DRP

Redundancy (Webster's) - serving as a

duplicate for preventing failure of an entire

system (as a spacecraft) upon failure of a

single component

Fault Tolerant (Webster's) - relating to or being

a computer or program with a self-contained backup system that allows continued

RAID

RAID

– Faster than a single

disk for reading

– Can lose a disk

Normal RAID 1 - 845

RAID 1 - Disk Duplexing (n/b)

What is parity?

– Writes can be slower, especially small writes

– Can lose single disk

– If disk lost you are in “critical mode”

• Another disk, total failure

• Slow operation while in critical mode

RAID 3 (similar to 5, easier to

explain)

RAID 5 (485)

Clustering!

Clustering

Clustering (Active/Passive) (n/b)

Clustering (Active/Active) (n/b)

If you like Clustering You’ll love virtualization! Unforutnately we don’t have time to go over it but Virtualization is the future and is

incredibly powerful and useful (and makes

administrators life… MUCH easier)

On your own, check out VMware vSphere or

Xen It’s well worth the time

Spare Parts (486)

When preparing your DRP, you should always consider the possibility that some equipment will be destroyed (maybe even RAID etc)

You should understand the MTTR and how

long replacement equipment or fixes will take, and if necessary stockpile spare parts!

Especially if you have legacy equipment

Legacy Equipment

Legacy Equipment

1982

Chapter 16 - Review

Q What is a Hot Site

Q What is a warm site

Q What is a cold Site

Q What is the difference between a Hot Site and a Mirror Site

Chapter 16 - Review

Q What is a Full Backup

Q What is an incremental Backup

Q What is a differential Backup?

Q What is a continuous Backup?

Chapter 16 - Review

Q What is RAID0

Q What is RAID1

Q What is RAID5

Q If I have 4 disks each 30G in a RAID 5, how

much usable storage do I have?