Business Continuity¶
Business continuity is the ability of an organization to maintain essential functions during, as well as after, a disaster has occurred. Business continuity planning establishes risk management processes and procedures that aim to prevent interruptions to mission-critical services, and re-establish full function to the organization as quickly and smoothly as possible.
Concepts¶
Business Continuity (BC)¶
Seeks to minimize business activity disruption when something unexpected happens.
Disaster Recovery (DR)¶
Act of responding to an event that thratens business continuity.
High Availability (HA)¶
Designing in redundancy to ensure that a system is always available.
Fault Tolerance¶
Designing in redundancy to ensure that a system can continue to operate in the event of a failure.
Service Level Agreement (SLA)¶
A contract between a service provider and a customer that specifies the level of service that the customer can expect.
Recovery Time Objective (RTO)¶
The maximum amount of time that a system can be down before it starts to impact the business.
Recovery Point Objective (RPO)¶
The maximum amount of data that can be lost before it starts to impact the business.
Types of disaster¶
| Category | Description |
|---|---|
| Hardware Failure | Failure of a physical component |
| Deployment Failure | Failure of a deployment |
| Load Induced | Distributed denial of Service attack on your website |
| Data Induced | Ariane 5 rocket explosion on June 1996 |
| Credential Expiration | An SSL/TLS certificate expires |
| Dependency | S3 subsystem failure cause numerous other AWS service failures |
| Infra | Lack of sufficient capacity |
| Human | Always a mistake made by someone |
Outputs¶
- General Concepts
- Know the difference between Business Continuity, Disaster Recovery, High Availability, and Fault Tolerance.
- Know the difference between Recovery Time Objective (RTO) and Recovery Point Objective (RPO).
- Understand the 4 options for Disaster Recovery: Backup and Restore, Pilot Light, Warm Standby, and Multi-Site.
- Storage Options
- Understand RAID and the potential benefits of using it.
- Compute Options
- Understand why horizontal scaling is preferred from an HA perspective.