You may want to upgrade a package you installed to the latest and greatest version. Helm provides the upgrade command, which operates intelligently and only updates things that have changed. For example, let's check the current values of our mariadb installation:
> helm get values cranky-whippet mariadbDatabase: awesome_stuff mariadbRootPassword: evenbettersecret
Now, let's run, upgrade, and change the name of the database:
> helm upgrade cranky-whippet --set mariadbDatabase=awesome_sauce stable/mariadb $ helm get values cranky-whippet mariadbDatabase: awesome_sauce
Note that we've lost our root password. All the existing values are replaced when you upgrade. OK, let's roll back. The helm history command shows us all the available revisions we can roll back to:
> helm history cranky-whippet REVISION STATUS CHART DESCRIPTION 1 SUPERSEDED mariadb-2.1.3 Install complete 2 SUPERSEDED mariadb-2.1.3 Upgrade complete 3 SUPERSEDED mariadb-2.1.3 Upgrade complete 4 DEPLOYED mariadb-2.1.3 Upgrade complete
Let's roll back to revision 3:
> helm rollback cranky-whippet 3
Rollback was a success! Happy Helming!
> helm history cranky-whippet
REVISION STATUS CHART DESCRIPTION
1 SUPERSEDED mariadb-2.1.3 Install complete
2 SUPERSEDED mariadb-2.1.3 Upgrade complete
3 SUPERSEDED mariadb-2.1.3 Upgrade complete
4 SUPERSEDED mariadb-2.1.3 Upgrade complete
5 DEPLOYED mariadb-2.1.3 Rollback to 3
Let's verify that our changes were rolled back:
> helm get values cranky-whippet mariadbDatabase: awesome_stuff mariadbRootPassword: evenbettersecret