Multi-site disaster recovery

Multi-site disaster recovery refers to replicating data and, depending on maturity, the services themselves onto a site geographically distinct from the production site, the only real protection against the total loss of a single site regardless of cause. Unlike intra-site redundancy, which protects against the failure of one component, multi-site continuity protects against the loss of the entire building, by ensuring a usable copy of the data and, ideally, a failover capacity for services survives elsewhere. The level of protection varies significantly with replication frequency, continuous versus periodic backups, and with the distance between sites, since a replica too close by remains exposed to the same regional event. For insurers, the existence, tested frequency and actual location of a multi-site continuity plan have become increasingly decisive underwriting criteria after several major losses revealed their absence at clients who believed themselves covered by their primary provider's robustness alone, a common confusion between a provider's operational resilience and protection against a total site loss.

After the 2021 fire at OVHcloud's Strasbourg site, clients who had replicated their data to a separate site were able to resume operations within hours, while those without such replication faced a prolonged outage or even permanent data loss.

multi-site disaster recovery, reprise d'activité géo-redondante, geo-redundant backup