An administrator, who operates a public cloud, has been tasked with implementing a secondary datacenter for failover purposes. Immediate replication has too much of an impact on the WAN link during…

Asynchronous replication does not require the primary site to wait for write confirmation from the secondary site before acknowledging I/O operations, so production workloads are unaffected by replication lag. This decoupling allows replication traffic to be batched and scheduled, preventing it from saturating the WAN link during production hours while still maintaining a secondary datacenter capable of failover.

Storage deduplication reduces the total volume of stored data but does not control when or how replication traffic is transmitted, so it does not relieve WAN congestion during production hours.

A cold site requires manual provisioning before it can accept failover traffic, making it unsuitable as an active replication target; offsite archiving provides point-in-time backups, not continuous replication.

Site mirroring relies on synchronous replication, which requires every write to be acknowledged by both sites in real time, increasing rather than reducing WAN utilization.