From NovaOrdis Knowledge Base
helm upgrade <release-name> <chart-name>
helm upgrade jazzy-manta archaeopteryx
Upgrade increments the revision number.
To keep a resource from being uninstalled during an upgrade, see helm uninstall - Keep a Resource from Being Uninstalled.
When upgrading, reuse the last release's values and merge in any overrides from the command line via
--reset-values is specified, this is ignored.
This is useful when the initial deployment was done with a configuration overlay, and we don't want to specify the same configuration overlay on upgrade.