Upgrading Elasticsearch version

An Elasticsearch cluster can be upgraded to a higher version in two ways:

• Rolling upgrade: This requires one node to stop at once and perform the upgradation.

• Full cluster restart: This requires a complete cluster shutdown before proceeding with the upgrade task.

You need to go through the following URL for more information on the supported versions to choose the type of upgrade you need to perform:

https://www.elastic.co/guide/en/elasticsearch/reference/current/setup-upgrade.html

In both cases, to upgrade a node, the following are the easiest steps to upgrade a version node by node:

1. Disable the routing allocation, as discussed in the previous section.

2. Stop the node.

3. Take a backup of the data.

4. Take a backup of the configuration files.

5. Remove Elasticsearch (you can simply purge it to complete the uninstallation of Elasticsearch from the server by running this command: sudo apt-get purge Elasticsearch)

6. Install Elasticsearch with the latest release.

7. Change the configuration...