Core Elasticsearch has been upgraded from 5.x version to 6.x. This is done in order to remove overheads in maintaining two versions of elasticsearch - One for Core services and other for Knowledge Platform. With this upgrade, we will be able to use a single elasticsearch cluster for both Core services and Knowledge Platform thereby benefitting in cost and maintenance. Please follow the below steps for this process.
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Restart elasticsearch service
sudo systemctl restart your_node_name_elasticsearch.service
curl -XPUT http://localhost:9200/_snapshot/azurebackup -H 'Content-Type: application/json' -d '{ "type": "azure", "settings": { "container": "elasticsearch-snapshots", "base_path": "application_elasticsearch"} }'
curl -XPUT http://localhost:9200/_snapshot/azurebackup/snapshot_back_name?wait_for_completion=true -H 'Content-Type: application/json' -d '{"include_global_state": false}'
Install jq: sudo apt-get install jq
Verify your backup was successful - curl http://localhost:9200/_snapshot/azurebackup/_all | jq
The above command will give you the snapshot name - "snapshot": "snapshot_1563878417" and "state": "SUCCESS"
Login to azure and verify in the storage account that backup files are created. The container name will be elasticsearch-snapshots and blob name will be application_elasticsearch