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"TRADITIONAL" STRATEGIES
There are a number of approaches that have been used in the past for the recovery of computer centers. Inasmuch as they involve long RTO's and extensive RPO's, they are inappropriate for most applications.
No Strategy
The least expensive strategy is to have no recovery or backup strategy. With this choice, data is not sent offsite, and there is no alternate site identified. There is no planned recovery document and any type of recovery will be accomplished by using on-site backups. Many times, healthcare organizations in this category use some type of incremental backup or physical volume backup method. This strategy is in direct violation of HIPAA.
Relocate, Rebuild, Restore
The relocate, restore, rebuild strategies are, by themselves, insufficient to meet the needs of today's businesses. However, plans to return the healthcare organization to a pre-disaster state must include these components. A primary reason for this is that after about 6 weeks at a commercial hot-site recovery facility, you will typically be asked to leave and your healthcare organization better have somewhere else to go.In an area wide disaster such as a hurricane, it is important to have vendors that will facilitate these three functions identified so that they can be called immediately following the disaster. In wide area disasters, vendor resources become scarce. The first few to contact the vendor will get services; all others will wait, perhaps for weeks or months.
Cold Site
A cold site is generally a facility that contains a raised floor space, redundant power, and HVAC (heating, ventilation, air conditioning, cooling). If a disaster occurs, the healthcare organization obtains the necessary data processing equipment and installs it at the cold site. This strategy has relatively low cost, but it is cumbersome to manage and the recovery time (RTO) is quite long. Because of today's dwindling RTOs, this strategy is becoming less acceptable as the only strategy but coupled with other strategies in a sequenced recovery, it is vary appropriate.
Hot Site
Commercial hot sites are typically designed to recover a computer facility within 12 to 72 hours after an event. To accomplish this, current backup tapes/disks must be available and a duplicate computer system/operating system/program set/communication network (hot-site) must be immediately available. The leading vendors for this service are IBM Business Continuity and Recovery Services (Appendix 3 for a request for proposal example.Once the vendors respond to the RFP, a decision matrix can be designed and used to determine the most cost-effective option.
Hot Site with Electronic Vaulting
Electronic vaulting means that data is backed up, and the output is electronically transmitted to an intermediate location or to a hot site for storage. One method of accomplishing this is to use standalone tape drives that receive and write data to removable tapes, which may be stored in racks or bins. Another method of electronic vaulting would be to incorporate an automated tape library, virtual tape library or direct access storage device.With Electronic Vaulting, there is a logical backup process which is staged to direct access or to tape prior to transmission. Healthcare organizations are more likely to achieve shorter recovery time if the electronic vault is located at the alternate site or connected to the alternate site through channels capable of long distance connectivity and high band width. Using this strategy, the amount of data loss can range from one day's worth to just a few minutes worth of data.
Active Recovery Site (Mirrored)
This strategy involves two active sites, each capable of taking over the other's workload in the event of a disaster. Each site will have enough idle processing power to restore data from the other site and to accommodate the excess workload in the event of a disaster. The two sites should be physically removed from each other and should be at greater than campus-wide separation if they are to handle regional disasters, such as floods or hurricanes.This strategy maintains selected data such that both copies of the data (local and remote copies) are in sync. This requires that updates to data be received at both the primary and secondary locations before the owning application is notified that the update is complete. This requires dedicated hardware at both sites, with the capability to automatically transfer the workload between sites.Using this strategy, virtually no data will be lost in the event of a disaster, thus providing for continuous availability. In a mainframe environment, achieving these capabilities requires control units capable of creating shadow copies of data and data synchronization, channel extenders, and channels with extended distance connection and high bandwidth. Achieving this strategy's objectives with distributed systems is not usually accomplished with channel extension technologies. Software-based solutions that send data over a shared network using a communication protocol such as TCP/IP are available for many distributed platforms.
