# ZooKeeper quorum
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The guidance sets up a ZooKeeper [quorum](concepts-and-definitions.md), consisting of the specified number of instances as defined in the CDK configuration. Metrics from these ZooKeeper instances are gathered and sent to CloudWatch under the metric namespace `AWSSolutions/Druid`.

The guidance additionally allocates an extra Elastic Network Interface (ENI) for each instance, enabling Druid to establish connections with ZooKeeper through static IP addresses.