Hosts in Elasticsearch resource group greater than MaxInstances

The default Elasticsearch installation is configured to use the ManagementHosts resource group and start the Elasticsearch data service up onto five management hosts in this resource group. If you have more than five management hosts in the ManagementHosts resource group, Elasticsearch shards might not be available depending on the hosts the Elasticsearch data services start on. In addition, the Elasticsearch service can remain in the TENTATIVE state.

You need to increase the maximum instances for the Elasticsearch data service to correspond to the number of management hosts in the ManagementHosts resource group to distribute the shards across all hosts in this resource group. For more information about scaling up service instances, see Scaling a service. In addition, consider Scaling Elasticsearch replicas to provide redundant copies of data to protect against hard failure.

Alternatively, you can create a new Elastic Stack resource group with five or fewer hosts and then switch Elasticsearch to use that group, instead of using the predefined ManagementHosts resource group. See Configuring Elasticsearch to use a different resource group.