A cloud administrator is load balancing six VMs on an IaaS cloud service. The organization has an SLA stating the application should be available 99.999% of the time. At present, the six VMs are handl

Adding only three VMs brings the total to nine, but if enough VMs fail during an AZ outage the remaining count could drop below the required six-VM capacity threshold.

By adding six VMs to the three existing availability zones, the total pool grows to twelve VMs, meaning the system can sustain the loss of up to six VMs while still meeting the baseline six-VM load requirement. This intra-region redundancy across three AZs supports the 99.999% SLA by eliminating single-AZ points of failure without the added operational complexity of multi-region failover.

Adding a second region with only three VMs means that region cannot independently handle the full load if the primary region fails, violating the minimum six-VM baseline requirement.

While a second region with six VMs provides geographic redundancy, it introduces multi-region complexity and potential latency that is not required when the existing three-AZ configuration within a single region already provides sufficient fault isolation for the stated SLA.