Takuya Tokuda
0502832cbb
* ordering content by weight * fix weight of 'setup' contents * fix weight of 'concepts' contents * fix weight of 'tasks' contents * fix weight of 'tutorials' contents * fix weight of 'reference' contents * Revert "fix weight of 'tasks' contents" This reverts commit 4b6916bed07c92c5f9eed75fb0a7ef0244266623. * Revert "fix weight of 'tutorials' contents" This reverts commit a1f783314337b1eb40017aef47a6bf1453d8c840. * Revert "fix weight of 'setup' contents" This reverts commit 91c8de366587eed25c803f8e7d5a59005adb6025. * Revert "fix weight of 'reference' contents" This reverts commit cc95605f6a9863f8a4ffb636178c69a80d302c3e.
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reviewers, title, content_template, weight
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Container Environment Variables | templates/concept | 20 |
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This page describes the resources available to Containers in the Container environment.
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Container environment
The Kubernetes Container environment provides several important resources to Containers:
- A filesystem, which is a combination of an image and one or more volumes.
- Information about the Container itself.
- Information about other objects in the cluster.
Container information
The hostname of a Container is the name of the Pod in which the Container is running.
It is available through the hostname command or the
gethostname
function call in libc.
The Pod name and namespace are available as environment variables through the downward API.
User defined environment variables from the Pod definition are also available to the Container, as are any environment variables specified statically in the Docker image.
Cluster information
A list of all services that were running when a Container was created is available to that Container as environment variables. Those environment variables match the syntax of Docker links.
For a service named foo that maps to a Container named bar, the following variables are defined:
FOO_SERVICE_HOST=<the host the service is running on>
FOO_SERVICE_PORT=<the port the service is running on>
Services have dedicated IP addresses and are available to the Container via DNS, if [DNS addon](http://releases.k8s.io/{{< param "githubbranch" >}}/cluster/addons/dns/) is enabled.
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- Learn more about Container lifecycle hooks.
- Get hands-on experience attaching handlers to Container lifecycle events.
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