Upgrading Elasticsearch
This is the process for in-place Elasticsearch (ES) upgrades, using an existing Search Feed and index data.
Required
This upgrade is for Elasticsearch 6.8.6 and 7.5.2 or higher with a Search Feed created on Swarm 11 or higher.
If you are using Elasticsearch 6.8.6, see How to Upgrade Swarm | Upgrading from Unsupported Elasticsearch for a specific version and live-upgrade ordering requirements.
See Migrating from Older Elasticsearch for migrating from Elasticsearch 2.3.3 or 5.6.12.
Elasticsearch cannot be downgraded once it’s upgraded.
Upgrading Elasticsearch by Script
On each node in an Elasticsearch cluster, follow this process and run the files from the Swarm download bundle:
Before upgrading, query the Elasticsearch cluster for the list of nodes.
curl -i http://ELASTICSEARCH:9200/_cat/nodes
Example output:
[root@elasticsearch Elasticsearch]# curl -i http://<ip-address>:9200/_cat/nodes HTTP/1.1 200 OK content-type: text/plain; charset=UTF-8 content-length: 300 <ip-node1> 14 99 1 0.02 0.14 0.15 dilm - <hostname-node1> <ip-node2> 1 71 1 0.01 0.09 0.08 dilm - <hostname-node2> <ip-node3> 72 99 0 0.08 0.06 0.08 dilm - <hostname-node3> <ip-node4> 50 99 0 0.03 0.04 0.05 dilm * <hostname-node4> <ip-node5> 47 99 1 0.08 0.14 0.22 dilm - <hostname-node5>
The node with * is the Elasticsearch master node. It is recommended to upgrade the node last to avoid problems electing a new master node.
Backup the existing configurations so a record exists of any customizations. Run
./techsupport-bundle-grab.sh
from your Support tools directory to backup to upgrade your support tools before running the script. Instructions are here.Install the latest Swarm Search i.e.
caringo-elasticsearch-search
RPM.yum install caringo-elasticsearch-search-VERSION.noarch.rpm
Tip
The error: "ES_PATH_CONF must be set to the configuration path chown: cannot access '/etc/elasticsearch/elasticsearch.keystore': No such file or directory
" is displayed if Elasticsearch 7 RPM was inadvertently installed. Install the caringo-elasticsearch-search
RPM to proceed.
Run the script to install and configure the upgrade.
If the script detects that Elasticsearch is installed and configured, it runs with--upgrade
instead of configuring a new cluster, automating the Elasticsearch rolling upgrade steps (Rolling upgrades | Elasticsearch Guide [7.17] | Elastic).
Important
The upgrade requires Internet access to download the Elasticsearch rpm. Place the elasticsearch-*.rpm
in the current directory if Internet access is unavailable.
Compare the backup file to the newly created
elasticsearch.yml
, add any customizations needed, and restartsystemctl restart elasticsearch
if the configuration was modified.
Verify that all nodes are accounted for, all shards are assigned, and the status is green.
The script updates the configuration files and restarts the service if the upgraded Elasticsearch is already installed.
Upgrading Elasticsearch Manually
The script automates the following steps for upgrading Elasticsearch manually:
It fixes
/etc/sysconfig/elasticsearch
to the correct ES6 version (the same as ES7+).It increases the
systemd
timeout in/etc/systemd/system/elasticsearch.service.d/override.conf
(see github.com/elastic/elasticsearch/issues/60140)A prompt to continue with the yum upgrade to the latest ES version appears after refreshing the config files for Elasticsearch 6.
It disables shard allocation and performs a POST synced-flush for safer rolling upgrades.
It uninstalls the existing Prometheus Exporter plugin.
It shells out to yum to install the Elasticsearch 7 RPM in the current directory or from artifacts.elastic.co, if unavailable.
It updates elasticsearch.yml for Elasticsearch 7+ compatibility, including
cluster.initial_master_nodes
instead ofdiscovery.zen.unicast.hosts
andjvm.options
.It starts the upgraded Elasticsearch and waits for it to be ready.
The cluster re-enables shard allocation and prompts to repeat these two steps on the next node if the cluster health is green or yellow.
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