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@@ -67,6 +67,42 @@ Replace `<networkname>` with the name of your docker-network.
 
 #### Others
 
+**Elasticsearch** is the search index and does not contain any data that cannot be restored, but performing a full reindex takes several hours (currently 4 for OPL), so you might consider taking backups. 
+
+Prepare backup area (only needed the first time):
+
+	sudo docker exec elasticsearch curl -XPUT 'localhost:9200/_snapshot/search_backup' -d '
+	{
+	      "type": "fs",
+	      "settings": {
+	          "location": "/usr/share/elasticsearch/data/backup",
+	          "compress": "true" 
+	      }
+	}'
+
+
+Take backup using:
+
+    sudo docker exec elasticsearch curl -XPUT 'localhost:9200/_snapshot/search_backup/snapshot_1?wait_for_completion=true'
+
+Restore from backup using:
+
+# Import backup to volume
+	docker run --rm \
+	   -v $(pwd):/from \
+	   -v <dockernetwork>_elasticsearch_data:/to \
+	    alpine ash -c "cd /to/backup ; tar -xf /from/esdata.tar" 
+	# Close index for writes
+	sudo docker exec elasticsearch curl -XPOST 'localhost:9200/search/_close'
+	# Restore:
+	sudo docker exec elasticsearch curl -XPOST 'localhost:9200/_snapshot/search_backup/snapshot_1/_restore'
+	# Open index for writes again
+	sudo docker exec elasticsearch curl -XPOST 'localhost:9200/search/_open'
+
+When we are deploying upgrades that requires a full reindex (due to changes in the Elasticsearch document mappings), we perform the indexing on a staging server, and copy the data to our production server using the backup/restore commands displayed above.
+
+* Koha Zebra index
+
 ## Customizations
 
 ### Internationalization