We're looking to migrate our clusters with ElasticSearch 2.x to the latest version. What is the simplest way to do this?
I already wrote a deploy script for deploying the ELK 2 stack and the ELK 6 stack. Unfortunately ElasticSearch 6.x cannot read data from ElasticSearch 2.x.
Go via ElasticSearch 5
Is it worth to make also a deploy script for an ELK-5, so it will automatically upgrade all my data without data loss? It's mostly logs.
Then we'd have to do 2 deploys on all environments and ElasticSearch would convert all data for us from the old to the newer version.
ElasticSearch 2 and 6 next to each other
Can we not better change the fluentd configuration to write log files to both ELK-2 and ELK-6 for a week at the same time. Then we delete the ELK-2 cluster a week later? That way we don't have to do weird stuff with building a new ElasticSearch-5 script and going through 2 deploys and 2 data upgrades.