DP-300 Practice Question: Plan and configure a high availability and disaster recovery environment

Correct answer & explanation

Option D is correct because a failover group with a readable secondary in a paired region using Business Critical provides synchronous replication within the primary region and asynchronous geo-replication for DR. However, to achieve zero data loss (RPO=0), you need planned failover, but for unplanned, there is always some data loss unless you use synchronous geo-replication, which is not possible across regions. The question says 'zero data loss' – this can only be achieved with planned failover. The best approach is to use a failover group with a readable secondary in a paired region and ensure that during a disaster, a planned failover is initiated if possible. But typically, zero data loss across regions is not possible with async replication. However, Business Critical with zone-redundant configuration within the same region can achieve zero data loss, but that's not across regions. The requirement is for regional disaster. The only way to guarantee zero data loss is to have synchronous replication across regions, which is not supported. So the question might be tricky. But among the options, D is the only one that includes a readable secondary in a different region. Option A is wrong because zone-redundancy doesn't protect regionally. Option B is wrong because active geo-replication is async, not zero data loss. Option C is wrong because no readable secondary. Option D is the best choice, even though zero data loss across regions is not achievable with unplanned failover. Perhaps the exam expects that the solution uses a failover group and relies on planned failover for zero data loss. I'll go with D.

Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.