Class FailureSimulator

java.lang.Object
com.eqixiac.equinix.design.resilience.FailureSimulator
public final class FailureSimulator extends Object
Simulates failure scenarios on one DesignGraph. Deterministic and side-effect free; build one per graph and call simulate(FailureScenario) for each scenario.

Rules

  1. A failed node takes every edge touching it; a metro failure takes the metro's router and on-ramps.
  2. Each workload runs in its primary metro or, failing that, its standby metro: whichever surviving host reaches more of its clouds, then more site weight (the primary on a tie). It is down when neither survives.
  3. A site reaches a host over its surviving access circuits and the backbone (shortest round trip); a host reaches a cloud through its Cloud Router, over a cloud connection in its own metro or, when that is gone, across the backbone to another metro's connection to the same cloud. Paths never transit another site or another cloud.
  4. A site counts as served only within the workload's maxLatencyMs and, for its access hop, the spec's maxLatencyMs; an unknown latency is not held against it.
  5. Capacity: every sized workload's bandwidth is put on the connection its path uses; when a connection's demand exceeds its capacity each workload on it gets capacity / demand. A connection of unknown capacity carries everything (and the report says so). Spill-over onto a third connection is not modelled.

  • Constructor Details

    • FailureSimulator

      public FailureSimulator(DesignGraph graph)
      Parameters:
      graph - the graph to simulate

  • Method Details