* Clustering is a group of servers or mule runtime which acts as a single unit.
* Mulesoft Enterprise Edition supports scalable clustering to provide high availability for the Mulesoft application.
* In simple terms, virtual servers composed of multiple nodes and they communicate and share information through a distributed shared memory grid.
* By default, Mulesoft ensures the High availability of applications if clustering implemented.
* Let's consider the scenario one of the nodes in cluster crashed or goes down and under maintenance. In such cases, Mulesoft will ensure that requests are processed by other nodes in the cluster. Mulesoft clustering also ensures that the request is load balanced between all the nodes in a cluster.
* Clustering is only supported by on-premise Mule runtime and it is not supported in Cloudhub.
Correct answer is External monitoring tools or log aggregators must be configured to recognize the new nodes
* Rest of the options are automatically taken care of when a new node is added in cluster.
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