sentinel implement in gateawy

As I know, Sentinel provides some implements in the gateway api module including flow control, and it transfers to param rule -> system rule. I want to know whether sentinel degrade implement in the cluster. I think it may need redis? zookeeper? or other?

Start by reviewing Sentinel's gateway API module, especially its flow-control implementation and the transfer from parameter rules to system rules. Determine whether cluster degradation requires Redis, ZooKeeper, or another coordination mechanism; done means documenting or implementing a clearly scoped cluster-degradation approach.

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