Hot-site

A backup site or work area recovery site is a location where an organization can relocate following a disaster, such as fire, flood, terrorist threat or other disruptive event. This is an integral part of the disaster recovery plan and wider business continuity planning of an organization.

A backup, or alternate, site can be another data center location operated by the organization, or contracted via a company that specializes in disaster recovery services. In some cases, one organization will have an agreement with a second organization to operate a joint backup site. In addition, an organization may have a reciprocal agreement with another organization to set up a warm site at each of their data centers.

There are three types of backup sites, including cold sites, warm sites, and hot sites. The differences between the types are determined by the costs and effort required to implement each.

In simple language, cold sites are mere empty operational spaces with basic facilities like raised floors, air conditioning, power and communication lines etc. On occurring of an incident and if the operations can do with a little down time, alternate facilities are brought to and set up in the cold site to resume operations. A cold site is the least expensive type of backup site for an organization to operate. It does not include backed up copies of data and information from the original location of the organization, nor does it include hardware already set up. The lack of provisioned hardware contributes to the minimal start-up costs of the cold site, but requires additional time following the disaster to have the operation running at a capacity close to that prior to the disaster. In some cases, a cold site may have equipment available, but it is not operational.

A warm site is a compromise between hot and cold. These sites will have hardware and connectivity already established, though on a smaller scale than the original production site or even a hot site. Warm sites might have backups on hand, but they may not be complete and may be between several days and a week old. The recovery will be delayed while backup tapes are delivered to the warm site, or network connectivity is established and data is recovered from a remote backup site (Example: SAN.)

A hot site is a duplicate of the original site of the organization, with full computer systems as well as near-complete backups of user data. Real time synchronization between the two sites may be used to completely mirror the data environment of the original site using wide area network links and specialized software. Following a disruption to the original site, the hot site exists so that the organization can relocate with minimal losses to normal operations in the shortest recovery time. Ideally, a hot site will be up and running within a matter of hours. Personnel may have to be moved to the hot site, but it is possible that the hot site may be operational from a data processing perspective before staff has relocated. The capacity of the hot site may or may not match the capacity of the original site depending on the organization's requirements. This type of backup site is the most expensive to operate. Hot sites are popular with organizations that operate real time processes such as financial institutions, government agencies and eCommerce providers. The most important feature offered from a hot site is that the production environment(s) is running concurrently with the main datacenter. This syncing allows for minimal impact and downtime to business operations. In the event of a significant outage event, the hot site can take the place of the impacted site immediately. However, this level of redundancy does not come cheap, and businesses will have to weigh the cost-benefit-analysis (CBA) of hot site utilization. Nowadays if the backup site is down and misses the "proactive" approach it may not be considered a hot site depending on the level of maturity of the organization regarding the ISO 22301 approach (international standard for Business Continuity Management).

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Wikipedia