kubeadm config

During kubeadm init, kubeadm uploads the ClusterConfiguration object to your cluster in a ConfigMap called kubeadm-config in the kube-system namespace. This configuration is then read during kubeadm join, kubeadm reset and kubeadm upgrade. To view this ConfigMap call kubeadm config view.

You can use kubeadm config print 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 view

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

-h, --help
help for view

Options inherited from parent commands

--kubeconfig string     Default: "/etc/kubernetes/admin.conf"
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
--rootfs string
[EXPERIMENTAL] The path to the 'real' host root filesystem.

kubeadm config print init-defaults

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" <nil> [] []} in order to pass validation but not perform the real computation for creating a token.

kubeadm config print init-defaults [flags]

Options

--component-configs stringSlice
A comma-separated list for component config API objects to print the default values for. Available values: [KubeProxyConfiguration KubeletConfiguration]. If this flag is not set, no component configs will be printed.
-h, --help
help for init-defaults

Options inherited from parent commands

--kubeconfig string     Default: "/etc/kubernetes/admin.conf"
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
--rootfs string
[EXPERIMENTAL] The path to the 'real' host root filesystem.

kubeadm config print join-defaults

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" <nil> [] []} in order to pass validation but not perform the real computation for creating a token.

kubeadm config print join-defaults [flags]

Options

--component-configs stringSlice
A comma-separated list for component config API objects to print the default values for. Available values: [KubeProxyConfiguration KubeletConfiguration]. If this flag is not set, no component configs will be printed.
-h, --help
help for join-defaults

Options inherited from parent commands

--kubeconfig string     Default: "/etc/kubernetes/admin.conf"
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
--rootfs string
[EXPERIMENTAL] The path to the 'real' host root filesystem.

kubeadm config migrate

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/v1beta2

Further, kubeadm can only write out config of version "kubeadm.k8s.io/v1beta2", 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

-h, --help
help for migrate
--new-config string
Path to the resulting equivalent kubeadm config file using the new API version. Optional, if not specified output will be sent to STDOUT.
--old-config string
Path to the kubeadm config file that is using an old API version and should be converted. This flag is mandatory.

Options inherited from parent commands

--kubeconfig string     Default: "/etc/kubernetes/admin.conf"
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
--rootfs string
[EXPERIMENTAL] The path to the 'real' host root filesystem.

kubeadm config images list

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

--allow-missing-template-keys     Default: true
If true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats.
--config string
Path to a kubeadm configuration file.
-o, --experimental-output string     Default: "text"
Output format. One of: text|json|yaml|go-template|go-template-file|template|templatefile|jsonpath|jsonpath-as-json|jsonpath-file.
--feature-gates string
A set of key=value pairs that describe feature gates for various features. Options are:
IPv6DualStack=true|false (ALPHA - default=false)
PublicKeysECDSA=true|false (ALPHA - default=false)
-h, --help
help for list
--image-repository string     Default: "k8s.gcr.io"
Choose a container registry to pull control plane images from
--kubernetes-version string     Default: "stable-1"
Choose a specific Kubernetes version for the control plane.

Options inherited from parent commands

--kubeconfig string     Default: "/etc/kubernetes/admin.conf"
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
--rootfs string
[EXPERIMENTAL] The path to the 'real' host root filesystem.

kubeadm config images pull

Synopsis

Pull images used by kubeadm

kubeadm config images pull [flags]

Options

--config string
Path to a kubeadm configuration file.
--cri-socket string
Path to the CRI socket to connect. If empty kubeadm will try to auto-detect this value; use this option only if you have more than one CRI installed or if you have non-standard CRI socket.
--feature-gates string
A set of key=value pairs that describe feature gates for various features. Options are:
IPv6DualStack=true|false (ALPHA - default=false)
PublicKeysECDSA=true|false (ALPHA - default=false)
-h, --help
help for pull
--image-repository string     Default: "k8s.gcr.io"
Choose a container registry to pull control plane images from
--kubernetes-version string     Default: "stable-1"
Choose a specific Kubernetes version for the control plane.

Options inherited from parent commands

--kubeconfig string     Default: "/etc/kubernetes/admin.conf"
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
--rootfs string
[EXPERIMENTAL] The path to the 'real' host root filesystem.

What's next

Last modified August 09, 2020 at 3:41 PM PST: add content_type param, kubeadm pages (1e0c50057)