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kubeadm config

Beginning with v1.8.0, kubeadm uploads the configuration of your cluster to a ConfigMap called kubeadm-config in the kube-system namespace, and later reads the ConfigMap when upgrading. This enables correct configuration of system components, and provides a seamless user experience.

You can execute kubeadm config view to view the ConfigMap. If you initialized your cluster using kubeadm v1.7.x or lower, you must use kubeadm config upload to create the ConfigMap before you may use kubeadm upgrade.

In Kubernetes v1.11.0, some new commands were added. You can use kubeadm config print-default to print the default configuration and kubeadm config migrate to convert your old configuration files to a newer version. kubeadm config images list and kubeadm config images pull can be used to list and pull the images that kubeadm requires.

In Kubernetes v1.13.0 and later to list/pull kube-dns images instead of the CoreDNS image the --config method described here has to be used.

• kubeadm config upload from-file
• kubeadm config upload from-flags
• kubeadm config view
• kubeadm config print init-defaults
• kubeadm config print join-defaults
• kubeadm config migrate
• kubeadm config images list
• kubeadm config images pull
• What's next

kubeadm config upload from-file

Upload a configuration file to the in-cluster ConfigMap for kubeadm configuration.

Synopsis

Using this command, you can upload configuration to the ConfigMap in the cluster using the same config file you gave to ‘kubeadm init’. If you initialized your cluster using a v1.7.x or lower kubeadm client and used the –config option, you need to run this command with the same config file before upgrading to v1.8 using ‘kubeadm upgrade’.

The configuration is located in the “kube-system” namespace in the “kubeadm-config” ConfigMap.

kubeadm config upload from-file [flags]

Options

Options inherited from parent commands

kubeadm config upload from-flags

Create the in-cluster configuration file for the first time from using flags.

Synopsis

Using this command, you can upload configuration to the ConfigMap in the cluster using the same flags you gave to ‘kubeadm init’. If you initialized your cluster using a v1.7.x or lower kubeadm client and set certain flags, you need to run this command with the same flags before upgrading to v1.8 using ‘kubeadm upgrade’.

The configuration is located in the “kube-system” namespace in the “kubeadm-config” ConfigMap.

kubeadm config upload from-flags [flags]

Options

Options inherited from parent commands

kubeadm config view

View the kubeadm configuration stored inside the cluster.

Synopsis

Using this command, you can view the ConfigMap in the cluster where the configuration for kubeadm is located.

The configuration is located in the “kube-system” namespace in the “kubeadm-config” ConfigMap.

kubeadm config view [flags]

Options

Options inherited from parent commands

kubeadm config print init-defaults

Print default init configuration, that can be used for ‘kubeadm init’

Synopsis

This command prints objects such as the default init configuration that is used for ‘kubeadm init’.

Note that sensitive values like the Bootstrap Token fields are replaced with placeholder values like {“abcdef.0123456789abcdef” “” “nil” [] []} in order to pass validation but not perform the real computation for creating a token.

kubeadm config print init-defaults [flags]

Options

Options inherited from parent commands

kubeadm config print join-defaults

Print default join configuration, that can be used for ‘kubeadm join’

Synopsis

This command prints objects such as the default join configuration that is used for ‘kubeadm join’.

Note that sensitive values like the Bootstrap Token fields are replaced with placeholder values like {“abcdef.0123456789abcdef” “” “nil” [] []} in order to pass validation but not perform the real computation for creating a token.

kubeadm config print join-defaults [flags]

Options

Options inherited from parent commands

kubeadm config migrate

Read an older version of the kubeadm configuration API types from a file, and output the similar config object for the newer version.

Synopsis

This command lets you convert configuration objects of older versions to the latest supported version, locally in the CLI tool without ever touching anything in the cluster. In this version of kubeadm, the following API versions are supported: - kubeadm.k8s.io/v1alpha3 - kubeadm.k8s.io/v1beta1

Further, kubeadm can only write out config of version “kubeadm.k8s.io/v1beta1”, but read both types. So regardless of what version you pass to the –old-config parameter here, the API object will be read, deserialized, defaulted, converted, validated, and re-serialized when written to stdout or –new-config if specified.

In other words, the output of this command is what kubeadm actually would read internally if you submitted this file to “kubeadm init”

kubeadm config migrate [flags]

Options

Options inherited from parent commands

kubeadm config images list

Print a list of images kubeadm will use. The configuration file is used in case any images or image repositories are customized.

Synopsis

Print a list of images kubeadm will use. The configuration file is used in case any images or image repositories are customized.

kubeadm config images list [flags]

Options

Options inherited from parent commands

kubeadm config images pull

Pull images used by kubeadm.

Synopsis

Pull images used by kubeadm.

kubeadm config images pull [flags]

Options

Options inherited from parent commands

What's next

• kubeadm upgrade to upgrade a Kubernetes cluster to a newer version

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