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This deployment is nearly identical to Multiple-Site High Availability for all zones, except that the sites are located in different regions, i.e. geographically separate. It is often referred to as “geographic disaster recovery”. This deployment type can be seen as an addition to a local HA deployment (one live site and one disaster recovery site), or a multi-site HA deployment (two or more live sites and one disaster recovery site).<picture>
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The inter-site latency in this case is assumed to be > 3 ms, making synchronous replication infeasible.
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