Update stateful workloads

This page explains how to update existing stateful workloads running in a Google Distributed Cloud (GDC) air-gapped appliance Kubernetes cluster. As your application evolves based on resource usage and configuration optimizations, you must update your underlying pod specification in the Kubernetes cluster to reflect those workload changes. For more information on planning updates for stateful workloads, see the Kubernetes documentation for Update strategies.

This page is for developers within the application operator group, who are responsible for updating application workloads for their organization.

Before you begin

To run commands against the pre-configured bare metal Kubernetes cluster, make sure you have the following resources:

Locate the Kubernetes cluster name, or ask your Platform Administrator what the cluster name is.
Sign in and generate the kubeconfig file for the Kubernetes cluster if you don't have one.
Use the kubeconfig path of the Kubernetes cluster to replace CLUSTER_KUBECONFIG in these instructions.

To get the required permissions to update stateful workloads, ask your Organization IAM Admin to grant you the Namespace Admin role (namespace-admin) in your project namespace.

Update a `StatefulSet` resource

To update the StatefulSet, apply a new or updated manifest file. This is useful for making various changes to your StatefulSet when scaling or for specifying a new version of your application.

To update a StatefulSet object, run:

kubectl --kubeconfig CLUSTER_KUBECONFIG -n NAMESPACE \
    apply -f STATEFULSET_FILE

Replace the following:

CLUSTER_KUBECONFIG: the kubeconfig file for the Kubernetes cluster running the stateful workloads.
NAMESPACE: the project namespace.
STATEFULSET_FILE: the name of the updated StatefulSet manifest file.

The kubectl apply command applies a manifest file to a resource. If the specified resource does not exist, it is created by the command.

Inspect a `StatefulSet` resource update rollout

You can view detailed information regarding the update rollout status and history of a StatefulSet object. You can also undo a rollout of a StatefulSet object.

Inspect the rollout

To inspect the rollout of the StatefulSet resource, run:

kubectl --kubeconfig CLUSTER_KUBECONFIG -n NAMESPACE \
    rollout status statefulset STATEFULSET_NAME

CLUSTER_KUBECONFIG: the kubeconfig file for the Kubernetes cluster running the stateful workloads.
NAMESPACE: the project namespace.
STATEFULSET_NAME: the name of the updated StatefulSet object.

Get the rollout history

To see the StatefulSet resource's rollout history, run:

kubectl --kubeconfig CLUSTER_KUBECONFIG -n NAMESPACE \
    rollout history statefulset STATEFULSET_NAME

CLUSTER_KUBECONFIG: the kubeconfig file for the Kubernetes cluster running the stateful workloads.
NAMESPACE: the project namespace.
STATEFULSET_NAME: the name of the updated StatefulSet object.

Undo a rollout

To undo a rollout, run:

kubectl --kubeconfig CLUSTER_KUBECONFIG -n NAMESPACE \
    rollout undo statefulset STATEFULSET_NAME