Geo-redundancy means that IT systems and data are maintained at geographically separated locations. If one site fails due to natural disaster, power outage, or fire, the other takes over.
The minimum distance between sites depends on the risk analysis — Germany’s BSI recommends at least 200 km for data centers. Geo-redundancy can be achieved through mirrored data centers, cloud regions, or backup sites. The challenge lies in data synchronization: synchronous replication guarantees data consistency but requires low latency; asynchronous replication is more tolerant but risks data loss up to the replication interval. In BCM and DR contexts, geo-redundancy is one of the most effective measures for availability.