139 lines
3.2 KiB
Markdown
139 lines
3.2 KiB
Markdown
---
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reviewers:
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- bprashanth
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- enisoc
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- erictune
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- foxish
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- janetkuo
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- kow3ns
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- smarterclayton
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title: Debug Init Containers
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content_type: task
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---
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<!-- overview -->
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This page shows how to investigate problems related to the execution of
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Init Containers. The example command lines below refer to the Pod as
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`<pod-name>` and the Init Containers as `<init-container-1>` and
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`<init-container-2>`.
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## {{% heading "prerequisites" %}}
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{{< include "task-tutorial-prereqs.md" >}} {{< version-check >}}
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* You should be familiar with the basics of
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[Init Containers](/docs/concepts/abstractions/init-containers/).
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* You should have [Configured an Init Container](/docs/tasks/configure-pod-container/configure-pod-initialization/#creating-a-pod-that-has-an-init-container/).
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<!-- steps -->
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## Checking the status of Init Containers
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Display the status of your pod:
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```shell
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kubectl get pod <pod-name>
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```
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For example, a status of `Init:1/2` indicates that one of two Init Containers
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has completed successfully:
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```
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NAME READY STATUS RESTARTS AGE
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<pod-name> 0/1 Init:1/2 0 7s
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```
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See [Understanding Pod status](#understanding-pod-status) for more examples of
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status values and their meanings.
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## Getting details about Init Containers
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View more detailed information about Init Container execution:
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```shell
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kubectl describe pod <pod-name>
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```
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For example, a Pod with two Init Containers might show the following:
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```
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Init Containers:
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<init-container-1>:
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Container ID: ...
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...
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State: Terminated
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Reason: Completed
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Exit Code: 0
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Started: ...
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Finished: ...
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Ready: True
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Restart Count: 0
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...
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<init-container-2>:
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Container ID: ...
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...
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State: Waiting
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Reason: CrashLoopBackOff
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Last State: Terminated
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Reason: Error
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Exit Code: 1
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Started: ...
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Finished: ...
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Ready: False
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Restart Count: 3
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...
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```
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You can also access the Init Container statuses programmatically by reading the
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`status.initContainerStatuses` field on the Pod Spec:
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```shell
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kubectl get pod nginx --template '{{.status.initContainerStatuses}}'
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```
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This command will return the same information as above in raw JSON.
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## Accessing logs from Init Containers
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Pass the Init Container name along with the Pod name
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to access its logs.
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```shell
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kubectl logs <pod-name> -c <init-container-2>
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```
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Init Containers that run a shell script print
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commands as they're executed. For example, you can do this in Bash by running
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`set -x` at the beginning of the script.
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<!-- discussion -->
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## Understanding Pod status
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A Pod status beginning with `Init:` summarizes the status of Init Container
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execution. The table below describes some example status values that you might
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see while debugging Init Containers.
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Status | Meaning
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------ | -------
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`Init:N/M` | The Pod has `M` Init Containers, and `N` have completed so far.
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`Init:Error` | An Init Container has failed to execute.
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`Init:CrashLoopBackOff` | An Init Container has failed repeatedly.
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`Pending` | The Pod has not yet begun executing Init Containers.
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`PodInitializing` or `Running` | The Pod has already finished executing Init Containers.
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