Do NOT trigger rollback during the running upgrade action! It may cause unpredictable OpenSearch state!
Manual Rollback
The upgrade can be halted and enter a failure state if, during the upgrade (i.e. after a juju refresh) there any version incompatibilities in charm revisions or it dependencies; or any other unexpected failure in the upgrade process.
Although the underlying OpenSearch continue to work, it’s important to rollback the charm to previous revision so an update can be later attempted after a further inspection of the failure.
To execute a rollback we take the same procedure as the upgrade, the difference being the charm revision to upgrade to. As an example following up the minor upgrades doc, one would refresh the charm back to revision 86, the steps being:
juju refresh opensearch --revision=87
When deploying from a local charm file, you need to have the previous revision’s .charm file. Then, run:
juju refresh opensearch --path=<path_to_charm_file>
After the refresh command, the juju controller revision for the application will be back in sync with the running OpenSearch revision.
Model Controller Cloud/Region Version SLA Timestamp
test localhost-localhost localhost/localhost 3.3.4 unsupported 13:02:15Z
App Version Status Scale Charm Channel Rev Exposed Message
opensearch active 3 opensearch 86 no
self-signed-certificates active 1 self-signed-certificates latest/stable 72 no
Unit Workload Agent Machine Public address Ports Message
opensearch/0* active idle 1 10.229.18.7 9200/tcp
opensearch/1 active idle 2 10.229.18.182 9200/tcp
opensearch/2 active idle 3 10.229.18.34 9200/tcp
self-signed-certificates/0* active idle 0 10.229.18.118
Machine State Address Inst id Base AZ Message
0 started 10.229.18.118 juju-d69356-0 ubuntu@22.04 Running
1 started 10.229.18.7 juju-d69356-1 ubuntu@22.04 Running
2 started 10.229.18.182 juju-d69356-2 ubuntu@22.04 Running
3 started 10.229.18.34 juju-d69356-3 ubuntu@22.04 Running
Check cluster health
Check the cluster is healthy. OpenSearch’s upstream documentation suggests the following check:
GET "/_cluster/health?pretty"
The response should look similar to the following example:
{
"cluster_name" : "test-cluster",
"status" : "green",
"timed_out" : false,
"number_of_nodes" : 3,
"number_of_data_nodes" : 3,
"discovered_master" : true,
"active_primary_shards" : 1,
...
"active_shards_percent_as_number" : 100.0
}