Do you happen to know if ES was the only storage? Its been almost 8 years, but if I was building a log storage and analysis system, then I'd push the logs to S3 or some other object store and build an ES index off of that S3 data. From the consumer's perspective, it may look like we're using ES to store the data, but we have a durable backup to regenerate ES if necessary.
Searchable snapshots in Elasticsearch can be backed by S3 and they perform very well. No need to store the data on hot nodes any longer than it takes for the index to do a rollover, and from then it's all S3.
