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Create a new search feed in the Swarm UI. Do not select Make primary.
Wait until the new feed has completed indexing the cluster, when the feed shows 0 "pending evaluation".
Make it the primary feed when the new feed is ready. Go Navigate to Cluster > Feeds, open the new Search feed, and select Make primary from the drop-down menu in the Swarm UI.
Operate with both feeds for several days. You can restore the old feed to be primary during troubleshooting if there is a problem.
Delete the old feed after this confirmation period. Go Navigate to Cluster > Feeds, open the old Search feed, and select Delete from the drop-down menu in the Swarm UI.
Delete the old index data to reclaim that space if desired.
Code Block curl -XDELETE 'http://old-elasticsearch:9200/_all' # do not do this to your production data!
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