Isolation Deployment Protocols for Re-ducing Production Risk in Multi-Datacenter Systems: An Extension of Zhao et al
Aim: This study aimed to extend the staged-rollout risk framework proposed by Zhao et al. (2018) to multi-datacenter environments by accounting for failure-domain topology, per-datacenter sequential monitoring, and automated rollback. The resulting framework, termed the Isolation Deployment Protocol (IDP), was designed to address the limitations of using traffic-percentage exposure as a proxy for failure exposure in distributed systems with shared control-plane services, replicated caches, and cross-region service-discovery dependencies. Methods: The Isolation Deployment Protocol (IDP) was developed by integrating four components: a real-time Failure Domain Graph Model, a Topology-Aware Ramp-Up (TARU) algorithm, per-datacenter Sequential Probability Ratio Test (SPRT) monitoring, and automated topology-aware rollback. IDP was evaluated on a six-node bare-metal Kubernetes testbed running Istio and Consul, with namespace isolation used to represent separate datacenters. Twenty independent trials were conducted against a topology-blind baseline, measuring realized blast radius and Mean Time to Containment (MTTC). The blast-radius model was also validated through formal analytical analysis. Results: Formal analysis demonstrated that the topology-blind baseline could underestimate blast radius by up to 8.62× in the evaluated failure scenario. Across 20 independent trials, IDP reduced the mean realized blast radius by a factor of 13.0 compared with the topology-blind baseline, restricting error propagation to the targeted 5% canary namespace. IDP also reduced Mean Time to Containment by 94.4%, from 142.4 minutes under global metric aggregation to 7.9 minutes with per-datacenter monitoring. These findings demonstrate that deployment decisions based on structural failure domains can substantially limit the propagation of failures beyond the intended canary population. Conclusion: These results indicate that topology-aware rollout control and per-datacenter monitoring can substantially reduce failure propagation and containment time relative to topology-blind global monitoring. Recommendation: The experiments ran within a single bare-metal host, and production multi-region network latency was not modeled; this represents an open limitation of the current evaluation. Future research should validate IDP across geographically distributed datacenters under realistic inter-region latency, packet loss, traffic variability, and production-scale dependency graphs.