Helm 3 was recently introduced which changed many of the internal bits within the CLI which are not fully backward compatible to those using Helm 2. Fear not, with a couple minor tweaks you can continue to use the Helm charts you know and love!
If you are a maintainer of Helm charts you should probably start with https://helm.sh/docs/faq/#changes-since-helm-2 to see how the changes impact you.
This post, however, focuses on the user experience of consuming charts other folks maintain. Below we’ll review how to install the PostgreSQL chart.
Using Helm install is Now 2 Steps
Helm 2 - Old Way
In the time of Lord Helm 2 installing a chart was as simple as:
helm install stable/postgresql
This assumed you would be using https://github.com/helm/charts as your chart repository.
Helm 3 - The New Way
It is fairly common to deploy helm charts by specifying the absolute url to a chart. With Helm 3+ you’ll need to do helm installs in two steps:
-
Add the chart repo to Helm:
helm repo add bitnami https://charts.bitnami.com
Note that there is a newer chart repository at https://hub.helm.sh.
-
Install the chart:
helm install bitnami/postgresql --version 8.1.2
Using the old charts with Helm 3
If you still wish to use the charts in https://github.com/helm/charts
with Helm 3, download the repo and specify the file path:
git clone https://github.com/helm/charts.git
cd charts/stable
helm install ./postgresql
Namespace is no longer automatically created
In Helm v2 you could specify a namespace during an install and if it didn’t exist, the namespace would be created automatically:
➜ helm2 install postgresql --name postgres2 --namespace=purple
The purple
namespace would be created automatically:
NAME STATUS AGE
default Active 83m
kube-node-lease Active 83m
kube-public Active 83m
kube-system Active 83m
purple Active 6m27s
Under Helm v3+ the orange
namespace is not created:
➜ helm3 install postgres3 ./postgresql --namespace=orange
Error: create: failed to create: namespaces "orange" not found
You’ll need to remember to create the namespace first until that functionality is added to many of the older charts.
No Tiller
You no longer need to do the helm init
dance, no server side components should make Helm easier to manage for operators in the long run. Hurray!
Miscellaneous
There are a few additional changes that happened with Helm 3:
helm del
is an alias forhelm uninstall
which no longer has a--purge
option since the uninstall cleans up the references.- When performing an install, there is no longer a
--name
option, the usage ishelm install [NAME] [CHART] [flags]
so simply provide the name as the first parameter to the install.
Otherwise, the helm charts themselves should still work. Enjoy!