For companies located in areas subject to earthquakes, they should establish a recovery site sufficiently distant from the primary data center so that the same earthquake cannot affect both buildings. If there is a requirement for synchronous replication in your data center, that would indicate that the recovery site should be within 125 kilometers of the primary site. Companies that fall into this category should consider a tertiary strategy, with the recovery site within 125 kilometers away and a third site farther away, and only able to support asynchronous replication. For companies with these requirements, cloud computing may be a viable alternative.
For more on IT disaster recovery planning and recovery sites:
This was first published in March 2010