Chapter 7. Disaster Recovery

Business continuity planning (BCP):
- Pertains to the overall continuation of business via a number of contingencies and alternative plans
Disaster recovery (DR):
- The set of processes and procedures that are used in order to reach the objectives of the Business Continuity Plan

Setting Objectives

Allow to
- Ensure that you are measurably meeting business requirements when creating a DR strategy
- To more easily make decisions regarding balancing time and budget considerations against uptime and recovery times
Recovery Point Objective:
- RPO is the point in time that you wish to recover to.
Recovery Time Objective:
- How long it takes to recover, taken irrespective of the RPO - After the disaster, how long until you have recovered to the point determined by the RPO.

Depend on RTO (Recovery Time Objective), RPO ( Recovery Point Objective), cost.
Backups:
- The most obvious strategy for recovering from a disaster
- Take backups of all systems and to restore those backups to new equipment
- Have a longer RPO than other strategies
Warm Standby:
- A secondary infrastructure, keep in approximate synchronization with primary infrastructure
- The RPO is fairly short, the RTO is however long the cut-over mechanism takes
High Availability:
- A model like a distributed cluster,
Alternate System
System Function Reassignment

Understand the dependencies of all system is an important part of developing a strategy for DR and BCP.
- By mapping out dependencies, it is much easier to identify unrealistic ROTs, or RTOs of other systems or services