Performing rolling roll back to DevOps Plan Helm chart

You can roll back DevOps Plan to the previous release using the helm rollback command.

Before you begin

Before you perform the upgrade, you must first do the following:

Use Helm to install the DevOps Plan solution chart as described in Step 5 of Getting started with DevOps Plan Helm chart.
Use Helm to upgrade the DevOps Plan chart to the new DevOps Plan release as described in Performing rolling upgrades to DevOps Plan Helm chart.

About this task

Rolling back utilizes the helm rollback command. For more information, see Helm Rollback in the Helm documentation.

Procedure

Run the helm history command to see revision numbers of your DevOps Plan helm chart release.
You should have a minimum of two revision numbers: revision 1 for installation and revision 2 that you used to upgrade to. The following example illustrates a helm chart release named hcl-devopsplan with revision 1 installed hcl-devopsplan3.0.2 for the DevOps Plan 3.0.2 release and revision 2 upgraded the helm chart hcl-devopsplan3.0.3 to the DevOps Plan 3.0.3 release.
```
$ helm history hcl-devopsplan --namespace dev
REVISION        UPDATED                         STATUS          CHART             APP VERSION              DESCRIPTION
1               Thu Jan 20 21:58:13 2022        superseded      hcl-devopsplan1-3.0.3          Install complete
2               Thu Jan 20 22:13:56 2022        deployed        hcl-devopsplan2-3.0.3          Upgrade complete
```
Roll back the DevOps Plan helm chart using the helm rollback command.
The following example will roll back the DevOps Plan helm chart release hcl-devopsplan from revision 2 to revision 1.
```
$ helm rollback hcl-devopsplan --namespace dev
Rollback was a success! Happy Helming!
```
Run the helm history RELEASE command to see that the new revision 3 has been created after roll back, and that it rolled back to revision 1 in the DevOps Plan helm chart release hcl-devopsplan1.
```
$ helm history hcl-devopsplan --namespace dev
REVISION        UPDATED                         STATUS          CHART             APP VERSION              DESCRIPTION
1               Thu Jan 20 21:58:13 2022        superseded      hcl-devopsplan1-3.0.2           Install complete
2               Thu Jan 20 22:13:56 2022        deployed        hcl-devopsplan2-3.0.3           Upgrade complete
3               Thu Jan 20 22:30:32 2022        deployed        hcl-devopsplan1-3.0.2           Rollback to 1
```
Note: When you rollback from helm chart release 3.0.3 to version 3.0.2, the OpenSearch version 2.18 indexes data that is saved in the OpenSearch Persistence volume and is not compatible with OpenSearch version 2.11, which is running on DevOps Plan 3.0.2. You must delete all data from the OpenSearch Persistence Volume /node folder before running the helm rollback command.