Bootstrap tokens are used for establishing bidirectional trust between a node joining the cluster and a control-plane node, as described in authenticating with bootstrap tokens.
kubeadm init
creates an initial token with a 24-hour TTL. The following commands allow you to manage such a token and also to create and manage new ones.
Create bootstrap tokens on the server
This command will create a bootstrap token for you. You can specify the usages for this token, the "time to live" and an optional human friendly description.
The [token] is the actual token to write. This should be a securely generated random token of the form "[a-z0-9]{6}.[a-z0-9]{16}". If no [token] is given, kubeadm will generate a random token instead.
kubeadm token create [token]
--certificate-key string | |
When used together with '--print-join-command', print the full 'kubeadm join' flag needed to join the cluster as a control-plane. To create a new certificate key you must use 'kubeadm init phase upload-certs --upload-certs'. | |
--config string | |
Path to a kubeadm configuration file. | |
--description string | |
A human friendly description of how this token is used. | |
--groups strings Default: "system:bootstrappers:kubeadm:default-node-token" | |
Extra groups that this token will authenticate as when used for authentication. Must match "\Asystem:bootstrappers:[a-z0-9:-]{0,255}[a-z0-9]\z" | |
-h, --help | |
help for create | |
--print-join-command | |
Instead of printing only the token, print the full 'kubeadm join' flag needed to join the cluster using the token. | |
--ttl duration Default: 24h0m0s | |
The duration before the token is automatically deleted (e.g. 1s, 2m, 3h). If set to '0', the token will never expire | |
--usages strings Default: "signing,authentication" | |
Describes the ways in which this token can be used. You can pass --usages multiple times or provide a comma separated list of options. Valid options: [signing,authentication] |
--dry-run | |
Whether to enable dry-run mode or not | |
--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. |
Delete bootstrap tokens on the server
This command will delete a list of bootstrap tokens for you.
The [token-value] is the full Token of the form "[a-z0-9]{6}.[a-z0-9]{16}" or the Token ID of the form "[a-z0-9]{6}" to delete.
kubeadm token delete [token-value] ...
-h, --help | |
help for delete |
--dry-run | |
Whether to enable dry-run mode or not | |
--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. |
Generate and print a bootstrap token, but do not create it on the server
This command will print out a randomly-generated bootstrap token that can be used with the "init" and "join" commands.
You don't have to use this command in order to generate a token. You can do so yourself as long as it is in the format "[a-z0-9]{6}.[a-z0-9]{16}". This command is provided for convenience to generate tokens in the given format.
You can also use "kubeadm init" without specifying a token and it will generate and print one for you.
kubeadm token generate [flags]
-h, --help | |
help for generate |
--dry-run | |
Whether to enable dry-run mode or not | |
--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. |
List bootstrap tokens on the server
This command will list all bootstrap tokens for you.
kubeadm token list [flags]
--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. | |
-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. | |
-h, --help | |
help for list | |
--show-managed-fields | |
If true, keep the managedFields when printing objects in JSON or YAML format. |
--dry-run | |
Whether to enable dry-run mode or not | |
--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. |
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Documentation Distributed under CC BY 4.0.
https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm-token