How to get Reserved Private Ip Address of Opensearch Service Data Nodes

CloudTrail does capture the Network Interfaces being created with the event name of CreateNetworkInterface. Inside the body of the response of the event there is also a field that contains the privateIpAddress used for the network interface.

If a B/G deployment is done where the number of data nodes is not changed on the domain then the ENI's associated with the OpenSearch domain are not changed. The existing ENI's simply get detached from the old data nodes and then attached on the new data nodes.

It's not possible to see the reserved private IP's of the new environment created for the B/G deployment until the resources have been swapped over.

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