IBM SC34-7012-01 manual Tier 2 physical removal with hot site, Tier 3 electronic vaulting

Tier 1

Tier 1 provides a very basic level of disaster recovery. You will lose data in the disaster, perhaps a considerable amount. However, tier 1 allows you to recover and provide some form of service at low cost. You must assess whether the loss of data and the time taken to restore a service will prevent your company from continuing in business.

Tier 2 - physical removal with hot site

Tier 2, like tier 1, provides a very basic level of disaster recovery. You will lose data in the disaster, perhaps a considerable amount.

However, tier 2 allows you to recover and provide some form of service at low cost and more rapidly than tier 1. You must assess whether the loss of data and the time taken to restore a service will prevent your company from continuing in business.

Figure 19 summarizes the tier 2 solution.

Warehouse Standby Site

Approach	Recovery
Backups kept off-site	Standby site costs
Procedures and inventory	Recovery time reduced
off-site
Recovery - restore system
and data, reconnect to
network

Figure 19. Disaster recovery tier 2: physical removal to a ‘hot’ standby site

Tier 2 is similar to tier 1. The difference in tier 2 is that a secondary site already has the necessary hardware installed, which can be made available to support the vital applications of the primary site. The same process is used to backup and store the vital data; therefore the same availability issues exist at the primary site as for tier 1.

The benefits of tier 2 are the elimination of the time it takes to obtain and setup the hardware at the secondary site, and the ability to test your disaster recovery plan.

The drawback is the expense of providing, or contracting for, a ‘hot’ standby site.

Tier 3 - electronic vaulting

Tier 3, like tiers 1 and 2, provides a basic level of disaster recovery. You will lose data in the disaster, perhaps a considerable amount of data.

Chapter 19. Disaster recovery 227