Kubectl wait: Difference between revisions
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=Overview= | =Overview= | ||
The command waits for a specific [[Kubernetes_Pod_and_Container_Concepts#Pod_Conditions|condition]], as reported by the ".status.conditions" field on a pod state, on one or many pods. If more than one pod is specified, the condition must be seen in every pod. Alternatively, the command can wait for a specific pod to be deleted. <font color=darkgray>The documentation mentions "resources" instead of pods. Can wait be applied for other things than pods? If yes, what is them meaning of "condition" in that context, as other resources may not have conditions?</font> | The command waits for a specific [[Kubernetes_Pod_and_Container_Concepts#Pod_Conditions|condition]], as reported by the ".status.conditions" field on a pod state, on one or many pods. If more than one pod is specified, the condition must be seen in every pod. Alternatively, the command can wait for a specific pod to be deleted. <font color=darkgray>The documentation mentions "resources" instead of pods. Can wait be applied for other things than pods? If yes, what is them meaning of "condition" in that context, as other resources may not have conditions?</font> The command exits with 0 if the resource is found and the conditions are met, or with a non-zero status if the resource is not found, or the condition is not met. | ||
=Wait for a Specific Condition= | =Wait for a Specific Condition= | ||
Revision as of 19:14, 20 September 2019
Internal
Overview
The command waits for a specific condition, as reported by the ".status.conditions" field on a pod state, on one or many pods. If more than one pod is specified, the condition must be seen in every pod. Alternatively, the command can wait for a specific pod to be deleted. The documentation mentions "resources" instead of pods. Can wait be applied for other things than pods? If yes, what is them meaning of "condition" in that context, as other resources may not have conditions? The command exits with 0 if the resource is found and the conditions are met, or with a non-zero status if the resource is not found, or the condition is not met.
Wait for a Specific Condition
Wait on a Pod Specified by Name
kubectl wait --for=condition=Ready pod <pod-name>
Wait on a Pod Specified by Label
kubectl wait --for=condition=Ready -l color=blue
For more details on selector syntax see option -l, --selector below.
Wait for Deletion
kubectl wait --for=delete pod <pod-name> --timeout=60s
Options
--timeout
The length of time to wait before giving up. Zero means check once and don't wait, negative means wait for a week.
The resource must exist for this option to be effective. If the resource is specified by name and does not exist, then the wait command exits immediately with an error message ("Error from server (NotFound): pods "..." not found"), irrespective of the timeout value. If the resource is specified by selector, the error message is "at least one resource must be specified to use a selector".
... --timeout=30s ...
-l, --selector
Specifies the selector (label query) to use to identify the resource. The expression supports '=', '==', and '!='.
-l key1=value1,key2!=value2