If I upgrade the chart, then the newer one overrides the older one and it is same as installing the newer chart
Is upgrade same as uninstalling a older release and installing a updated chart with the same release name ?
If it is same, then what is the use of upgrade ?
Hi @dnpuneeth3,
The install command used to install a chart, you must supply the helm chart reference to install it.
The example of installing mysql:
$ helm repo add my-repo https://charts.bitnami.com/bitnami
$ helm install my-release my-repo/mysql
On the other hand, helm upgrade modifies the existing release of a specific chart.
helm upgrade my-release my-repo/mysql
So install create an instance (release) of a chart, while upgrade update/modify the existing instance (release) of a specific chart.
Hope it clear.
Happy learning,
Trung.
when chart is upgraded, will it uninstall the older instance k8s objects and install new k8s object ?
Hi @dnpuneeth3,
It will update the k8s objects like deployment or statefulset to the required version (new image), so it will delete the old version pod and create a new one.
You can try to install a mysql chart at version 9.3.5, then upgrade to the latest version and see the event (kubectl describe statefulset) in the MySQL stateful set, you will see it deletes the old pod and create a new one with a new version.
More can be found here: Helm | Helm Upgrade
Happy learning,
Trung.
Does it update only specific objects such as deployment or statefulset or all the objects? what are the objects that does not update ?
Hello @dnpuneeth3,
It depends on the helm chart, can you give me the chart that you’re using so we can discuss the same thing?
Happy learning,
Trung.