What is disaster recovery?

Disaster Recovery is a concept that insists on planning for computing failures in one or many computing devices. For IT systems that support business functions, a Disaster Recovery Plan (DNP) and recovery technologies are essential, given our reliance on computers. Businesses need to keep critical aspects of their daily processes functioning even in the midst of disruptive events, whether they are natural or human-error malfunctions. Disaster Recovery should include quick resumption of applications and communications (such as networking) along with the backup revival of data, hardware, and other IT infrastructure.

To illustrate just how critical basic disaster recovery can be, there is a study titled "Backing Up Business - Industry Trend or Event" that discovered a significant business impact in massive data loss. Out of the companies that endured a major loss of business data, only 6% survived long term. 43% were never able to revive their business and 51% were forced to close within two years.

A DRP is the IT-related section of a Business Continuity Plan (BCP), which includes planning for non-IT aspects of a recovery such as responsibilities and public relations during a crisis. Organizations have three types of measures against disaster events:

Preventative Measures: aimed at preventing disaster events
Detective Measures: intended to discover a disaster event as early as possible
Corrective Measures: designed to contain a disaster and recover from it

Recovery plans will sometimes include metrics to indicate how effective a recovery was. These include a recovery point objective (RPO) and a recovery time objective (RTO).

Data Recovery
Less advanced strategies for data protection will include tape backups that are sent off site. Most backups are written to disk and automatically copied to off-site disks for large corporations. SANs can make the restoration process much quicker by simply allowing interconnected backups to synchronize with the primary storage when data restoration is required (servers can boot from the SAN itself). High availablility systems keep both the data and the system replicated off-site for continuous access to both.

Disaster Prevention
Organizations need to implement precautionary strategies as well as recovery strategies in order to further minimize the impact of malfunctions on their business. Here are some strategies that fall under preventative measures and/or detective measures:

• Local system and data mirrors
• Disk protection technology (e.g. RAID)
• Electrical surge protectors
• A backup or uninterruptible power supply
• Fire alarms, sprinklers, and extinguishers
• Anti-virus and other security software.

An organization can choose from a variety of different disaster recovery service and technology packages from industry vendors if they don’t want to deal with recovery themselves.