Page 1320 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

setups transfer copies of the database transaction logs containing the
transactions that occurred since the previous bulk transfer.

Remote journaling is similar to electronic vaulting in that transaction

logs transferred to the remote site are not applied to a live database
server but are maintained in a backup device. When a disaster is
declared, technicians retrieve the appropriate transaction logs and
apply them to the production database, bringing the database up to
the current production state.

Remote Mirroring

Remote mirroring is the most advanced database backup solution.

Not surprisingly, it’s also the most expensive! Remote mirroring goes
beyond the technology used by remote journaling and electronic
vaulting; with remote mirroring, a live database server is maintained
at the backup site. The remote server receives copies of the database
modifications at the same time they are applied to the production
server at the primary site. Therefore, the mirrored server is ready to

take over an operational role at a moment’s notice.

Remote mirroring is a popular database backup strategy for
organizations seeking to implement a hot site. However, when
weighing the feasibility of a remote mirroring solution, be sure to take
into account the infrastructure and personnel costs required to
support the mirrored server as well as the processing overhead that
will be added to each database transaction on the mirrored server.