Typo fix: formated->formatted and proper noun in capital (#8332)
* Typo fix: formated->formatted and proper noun in capital formated->formatted Pod and Container are proper noun, in this doc, someplace are in capital, some are in lowercase. It's better to keep consistency. * Update volumes.md
This commit is contained in:
@@ -10,14 +10,14 @@ content_template: templates/concept
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{{% capture overview %}}
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On-disk files in a container are ephemeral, which presents some problems for
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non-trivial applications when running in containers. First, when a container
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On-disk files in a Container are ephemeral, which presents some problems for
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non-trivial applications when running in Containers. First, when a Container
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crashes, kubelet will restart it, but the files will be lost - the
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container starts with a clean state. Second, when running containers together
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in a `Pod` it is often necessary to share files between those containers. The
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Container starts with a clean state. Second, when running Containers together
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in a `Pod` it is often necessary to share files between those Containers. The
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Kubernetes `Volume` abstraction solves both of these problems.
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Familiarity with [pods](/docs/user-guide/pods) is suggested.
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Familiarity with [Pods](/docs/user-guide/pods) is suggested.
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{{% /capture %}}
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@@ -30,27 +30,27 @@ Familiarity with [pods](/docs/user-guide/pods) is suggested.
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Docker also has a concept of
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[volumes](https://docs.docker.com/engine/admin/volumes/), though it is
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somewhat looser and less managed. In Docker, a volume is simply a directory on
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disk or in another container. Lifetimes are not managed and until very
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disk or in another Container. Lifetimes are not managed and until very
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recently there were only local-disk-backed volumes. Docker now provides volume
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drivers, but the functionality is very limited for now (e.g. as of Docker 1.7
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only one volume driver is allowed per container and there is no way to pass
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only one volume driver is allowed per Container and there is no way to pass
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parameters to volumes).
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A Kubernetes volume, on the other hand, has an explicit lifetime - the same as
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the pod that encloses it. Consequently, a volume outlives any containers that run
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the Pod that encloses it. Consequently, a volume outlives any Containers that run
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within the Pod, and data is preserved across Container restarts. Of course, when a
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Pod ceases to exist, the volume will cease to exist, too. Perhaps more
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importantly than this, Kubernetes supports many types of volumes, and a Pod can
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use any number of them simultaneously.
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At its core, a volume is just a directory, possibly with some data in it, which
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is accessible to the containers in a pod. How that directory comes to be, the
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is accessible to the Containers in a Pod. How that directory comes to be, the
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medium that backs it, and the contents of it are determined by the particular
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volume type used.
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To use a volume, a pod specifies what volumes to provide for the pod (the
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To use a volume, a Pod specifies what volumes to provide for the Pod (the
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`spec.volumes`
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field) and where to mount those into containers (the
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field) and where to mount those into Containers (the
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`spec.containers.volumeMounts`
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field).
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@@ -59,7 +59,7 @@ image and volumes. The [Docker
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image](https://docs.docker.com/userguide/dockerimages/) is at the root of the
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filesystem hierarchy, and any volumes are mounted at the specified paths within
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the image. Volumes can not mount onto other volumes or have hard links to
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other volumes. Each container in the Pod must independently specify where to
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other volumes. Each Container in the Pod must independently specify where to
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mount each volume.
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## Types of Volumes
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@@ -98,11 +98,11 @@ We welcome additional contributions.
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### awsElasticBlockStore
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An `awsElasticBlockStore` volume mounts an Amazon Web Services (AWS) [EBS
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Volume](http://aws.amazon.com/ebs/) into your pod. Unlike
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Volume](http://aws.amazon.com/ebs/) into your Pod. Unlike
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`emptyDir`, which is erased when a Pod is removed, the contents of an EBS
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volume are preserved and the volume is merely unmounted. This means that an
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EBS volume can be pre-populated with data, and that data can be "handed off"
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between pods.
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between Pods.
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{{< caution >}}
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**Important:** You must create an EBS volume using `aws ec2 create-volume` or the AWS API before you can use it.
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@@ -110,13 +110,13 @@ between pods.
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There are some restrictions when using an `awsElasticBlockStore` volume:
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* the nodes on which pods are running must be AWS EC2 instances
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* the nodes on which Pods are running must be AWS EC2 instances
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* those instances need to be in the same region and availability-zone as the EBS volume
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* EBS only supports a single EC2 instance mounting a volume
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#### Creating an EBS volume
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Before you can use an EBS volume with a pod, you need to create it.
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Before you can use an EBS volume with a Pod, you need to create it.
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```shell
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aws ec2 create-volume --availability-zone=eu-west-1a --size=10 --volume-type=gp2
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@@ -163,10 +163,10 @@ More details can be found [here](https://github.com/kubernetes/examples/tree/{{<
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### cephfs
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A `cephfs` volume allows an existing CephFS volume to be
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mounted into your pod. Unlike `emptyDir`, which is erased when a Pod is
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mounted into your Pod. Unlike `emptyDir`, which is erased when a Pod is
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removed, the contents of a `cephfs` volume are preserved and the volume is merely
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unmounted. This means that a CephFS volume can be pre-populated with data, and
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that data can be "handed off" between pods. CephFS can be mounted by multiple
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that data can be "handed off" between Pods. CephFS can be mounted by multiple
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writers simultaneously.
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{{< caution >}}
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@@ -219,7 +219,7 @@ keyed with `log_level`.
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{{< /caution >}}
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{{< note >}}
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**Note:** A container using a ConfigMap as a [subPath](#using-subpath) volume mount will not
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**Note:** A Container using a ConfigMap as a [subPath](#using-subpath) volume mount will not
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receive ConfigMap updates.
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{{< /note >}}
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@@ -229,7 +229,7 @@ A `downwardAPI` volume is used to make downward API data available to applicatio
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It mounts a directory and writes the requested data in plain text files.
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{{< note >}}
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**Note:** A container using Downward API as a [subPath](#using-subpath) volume mount will not
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**Note:** A Container using Downward API as a [subPath](#using-subpath) volume mount will not
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receive Downward API updates.
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{{< /note >}}
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@@ -239,31 +239,31 @@ See the [`downwardAPI` volume example](/docs/tasks/inject-data-application/downw
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An `emptyDir` volume is first created when a Pod is assigned to a Node, and
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exists as long as that Pod is running on that node. As the name says, it is
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initially empty. Containers in the pod can all read and write the same
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initially empty. Containers in the Pod can all read and write the same
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files in the `emptyDir` volume, though that volume can be mounted at the same
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or different paths in each container. When a Pod is removed from a node for
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or different paths in each Container. When a Pod is removed from a node for
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any reason, the data in the `emptyDir` is deleted forever.
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{{< note >}}
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**Note:** a container crashing does *NOT* remove a pod from a node, so the data in an `emptyDir` volume is safe across container crashes.
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**Note:** a Container crashing does *NOT* remove a Pod from a node, so the data in an `emptyDir` volume is safe across Container crashes.
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{{< /note >}}
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Some uses for an `emptyDir` are:
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* scratch space, such as for a disk-based merge sort
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* checkpointing a long computation for recovery from crashes
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* holding files that a content-manager container fetches while a webserver
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container serves the data
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* holding files that a content-manager Container fetches while a webserver
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Container serves the data
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By default, `emptyDir` volumes are stored on whatever medium is backing the
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node - that might be disk or SSD or network storage, depending on your
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environment. However, you can set the `emptyDir.medium` field to `"Memory"`
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to tell Kubernetes to mount a tmpfs (RAM-backed filesystem) for you instead.
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While tmpfs is very fast, be aware that unlike disks, tmpfs is cleared on
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node reboot and any files you write will count against your container's
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node reboot and any files you write will count against your Container's
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memory limit.
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#### Example pod
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#### Example Pod
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```yaml
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apiVersion: v1
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@@ -284,7 +284,7 @@ spec:
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### fc (fibre channel)
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An `fc` volume allows an existing fibre channel volume to be mounted in a pod.
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An `fc` volume allows an existing fibre channel volume to be mounted in a Pod.
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You can specify single or multiple target World Wide Names using the parameter
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`targetWWNs` in your volume configuration. If multiple WWNs are specified,
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targetWWNs expect that those WWNs are from multi-path connections.
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@@ -297,14 +297,14 @@ See the [FC example](https://github.com/kubernetes/examples/tree/{{< param "gith
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### flocker
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[Flocker](https://github.com/ClusterHQ/flocker) is an open-source clustered container data volume manager. It provides management
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[Flocker](https://github.com/ClusterHQ/flocker) is an open-source clustered Container data volume manager. It provides management
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and orchestration of data volumes backed by a variety of storage backends.
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A `flocker` volume allows a Flocker dataset to be mounted into a pod. If the
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A `flocker` volume allows a Flocker dataset to be mounted into a Pod. If the
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dataset does not already exist in Flocker, it needs to be first created with the Flocker
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CLI or by using the Flocker API. If the dataset already exists it will be
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reattached by Flocker to the node that the pod is scheduled. This means data
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can be "handed off" between pods as required.
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reattached by Flocker to the node that the Pod is scheduled. This means data
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can be "handed off" between Pods as required.
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{{< caution >}}
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**Important:** You must have your own Flocker installation running before you can use it.
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@@ -315,10 +315,10 @@ See the [Flocker example](https://github.com/kubernetes/examples/tree/{{< param
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### gcePersistentDisk
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A `gcePersistentDisk` volume mounts a Google Compute Engine (GCE) [Persistent
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Disk](http://cloud.google.com/compute/docs/disks) into your pod. Unlike
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Disk](http://cloud.google.com/compute/docs/disks) into your Pod. Unlike
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`emptyDir`, which is erased when a Pod is removed, the contents of a PD are
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preserved and the volume is merely unmounted. This means that a PD can be
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pre-populated with data, and that data can be "handed off" between pods.
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pre-populated with data, and that data can be "handed off" between Pods.
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{{< caution >}}
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**Important:** You must create a PD using `gcloud` or the GCE API or UI before you can use it.
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@@ -326,27 +326,27 @@ pre-populated with data, and that data can be "handed off" between pods.
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There are some restrictions when using a `gcePersistentDisk`:
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* the nodes on which pods are running must be GCE VMs
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* the nodes on which Pods are running must be GCE VMs
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* those VMs need to be in the same GCE project and zone as the PD
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A feature of PD is that they can be mounted as read-only by multiple consumers
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simultaneously. This means that you can pre-populate a PD with your dataset
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and then serve it in parallel from as many pods as you need. Unfortunately,
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and then serve it in parallel from as many Pods as you need. Unfortunately,
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PDs can only be mounted by a single consumer in read-write mode - no
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simultaneous writers allowed.
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Using a PD on a pod controlled by a ReplicationController will fail unless
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Using a PD on a Pod controlled by a ReplicationController will fail unless
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the PD is read-only or the replica count is 0 or 1.
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#### Creating a PD
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Before you can use a GCE PD with a pod, you need to create it.
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Before you can use a GCE PD with a Pod, you need to create it.
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```shell
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gcloud compute disks create --size=500GB --zone=us-central1-a my-data-disk
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```
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#### Example pod
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#### Example Pod
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```yaml
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apiVersion: v1
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@@ -371,7 +371,7 @@ spec:
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### gitRepo
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A `gitRepo` volume is an example of what can be done as a volume plugin. It
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mounts an empty directory and clones a git repository into it for your pod to
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mounts an empty directory and clones a git repository into it for your Pod to
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use. In the future, such volumes may be moved to an even more decoupled model,
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rather than extending the Kubernetes API for every such use case.
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@@ -399,11 +399,11 @@ spec:
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### glusterfs
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A `glusterfs` volume allows a [Glusterfs](http://www.gluster.org) (an open
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source networked filesystem) volume to be mounted into your pod. Unlike
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source networked filesystem) volume to be mounted into your Pod. Unlike
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`emptyDir`, which is erased when a Pod is removed, the contents of a
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`glusterfs` volume are preserved and the volume is merely unmounted. This
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means that a glusterfs volume can be pre-populated with data, and that data can
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be "handed off" between pods. GlusterFS can be mounted by multiple writers
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be "handed off" between Pods. GlusterFS can be mounted by multiple writers
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simultaneously.
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{{< caution >}}
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@@ -415,16 +415,16 @@ See the [GlusterFS example](https://github.com/kubernetes/examples/tree/{{< para
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### hostPath
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A `hostPath` volume mounts a file or directory from the host node's filesystem
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into your pod. This is not something that most Pods will need, but it offers a
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into your Pod. This is not something that most Pods will need, but it offers a
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powerful escape hatch for some applications.
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For example, some uses for a `hostPath` are:
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* running a container that needs access to Docker internals; use a `hostPath`
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* running a Container that needs access to Docker internals; use a `hostPath`
|
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of `/var/lib/docker`
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* running cAdvisor in a container; use a `hostPath` of `/sys`
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* allowing a pod to specify whether a given `hostPath` should exist prior to the
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pod running, whether it should be created, and what it should exist as
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* running cAdvisor in a Container; use a `hostPath` of `/sys`
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* allowing a Pod to specify whether a given `hostPath` should exist prior to the
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Pod running, whether it should be created, and what it should exist as
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In addition to the required `path` property, user can optionally specify a `type` for a `hostPath` volume.
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@@ -444,16 +444,16 @@ The supported values for field `type` are:
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Watch out when using this type of volume, because:
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||||
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* pods with identical configuration (such as created from a podTemplate) may
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* Pods with identical configuration (such as created from a podTemplate) may
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behave differently on different nodes due to different files on the nodes
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||||
* when Kubernetes adds resource-aware scheduling, as is planned, it will not be
|
||||
able to account for resources used by a `hostPath`
|
||||
* the files or directories created on the underlying hosts are only writable by root. You
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||||
either need to run your process as root in a
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[privileged container](/docs/user-guide/security-context) or modify the file
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||||
[privileged Container](/docs/user-guide/security-context) or modify the file
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permissions on the host to be able to write to a `hostPath` volume
|
||||
|
||||
#### Example pod
|
||||
#### Example Pod
|
||||
|
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```yaml
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apiVersion: v1
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@@ -479,10 +479,10 @@ spec:
|
||||
### iscsi
|
||||
|
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An `iscsi` volume allows an existing iSCSI (SCSI over IP) volume to be mounted
|
||||
into your pod. Unlike `emptyDir`, which is erased when a Pod is removed, the
|
||||
into your Pod. Unlike `emptyDir`, which is erased when a Pod is removed, the
|
||||
contents of an `iscsi` volume are preserved and the volume is merely
|
||||
unmounted. This means that an iscsi volume can be pre-populated with data, and
|
||||
that data can be "handed off" between pods.
|
||||
that data can be "handed off" between Pods.
|
||||
|
||||
{{< caution >}}
|
||||
**Important:** You must have your own iSCSI server running with the volume created before you can use it.
|
||||
@@ -490,7 +490,7 @@ that data can be "handed off" between pods.
|
||||
|
||||
A feature of iSCSI is that it can be mounted as read-only by multiple consumers
|
||||
simultaneously. This means that you can pre-populate a volume with your dataset
|
||||
and then serve it in parallel from as many pods as you need. Unfortunately,
|
||||
and then serve it in parallel from as many Pods as you need. Unfortunately,
|
||||
iSCSI volumes can only be mounted by a single consumer in read-write mode - no
|
||||
simultaneous writers allowed.
|
||||
|
||||
@@ -514,12 +514,12 @@ Local volumes can only be used as a statically created PersistentVolume. Dynamic
|
||||
provisioning is not supported yet.
|
||||
|
||||
Compared to `hostPath` volumes, local volumes can be used in a durable and
|
||||
portable manner without manually scheduling pods to nodes, as the system is aware
|
||||
portable manner without manually scheduling Pods to nodes, as the system is aware
|
||||
of the volume's node constraints by looking at the node affinity on the PersistentVolume.
|
||||
|
||||
However, local volumes are still subject to the availability of the underlying
|
||||
node and are not suitable for all applications. If a node becomes unhealthy,
|
||||
then the local volume will also become inaccessible, and a pod using it will not
|
||||
then the local volume will also become inaccessible, and a Pod using it will not
|
||||
be able to run. Applications using local volumes must be able to tolerate this
|
||||
reduced availability, as well as potential data loss, depending on the
|
||||
durability characteristics of the underlying disk.
|
||||
@@ -554,7 +554,7 @@ spec:
|
||||
```
|
||||
|
||||
PersistentVolume `nodeAffinity` is required when using local volumes. It enables
|
||||
the Kubernetes scheduler to correctly schedule pods using local volumes to the
|
||||
the Kubernetes scheduler to correctly schedule Pods using local volumes to the
|
||||
correct node.
|
||||
|
||||
PersistentVolume `volumeMode` can now be set to "Block" (instead of the default
|
||||
@@ -565,8 +565,8 @@ When using local volumes, it is recommended to create a StorageClass with
|
||||
`volumeBindingMode` set to `WaitForFirstConsumer`. See the
|
||||
[example](storage-classes.md#local). Delaying volume binding ensures
|
||||
that the PersistentVolumeClaim binding decision will also be evaluated with any
|
||||
other node constraints the pod may have, such as node resource requirements, node
|
||||
selectors, pod affinity, and pod anti-affinity.
|
||||
other node constraints the Pod may have, such as node resource requirements, node
|
||||
selectors, Pod affinity, and Pod anti-affinity.
|
||||
|
||||
An external static provisioner can be run separately for improved management of
|
||||
the local volume lifecycle. Note that this provisioner does not support dynamic
|
||||
@@ -582,10 +582,10 @@ lifecycle.
|
||||
### nfs
|
||||
|
||||
An `nfs` volume allows an existing NFS (Network File System) share to be
|
||||
mounted into your pod. Unlike `emptyDir`, which is erased when a Pod is
|
||||
mounted into your Pod. Unlike `emptyDir`, which is erased when a Pod is
|
||||
removed, the contents of an `nfs` volume are preserved and the volume is merely
|
||||
unmounted. This means that an NFS volume can be pre-populated with data, and
|
||||
that data can be "handed off" between pods. NFS can be mounted by multiple
|
||||
that data can be "handed off" between Pods. NFS can be mounted by multiple
|
||||
writers simultaneously.
|
||||
|
||||
{{< caution >}}
|
||||
@@ -597,7 +597,7 @@ See the [NFS example](https://github.com/kubernetes/examples/tree/{{< param "git
|
||||
### persistentVolumeClaim
|
||||
|
||||
A `persistentVolumeClaim` volume is used to mount a
|
||||
[PersistentVolume](/docs/concepts/storage/persistent-volumes/) into a pod. PersistentVolumes are a
|
||||
[PersistentVolume](/docs/concepts/storage/persistent-volumes/) into a Pod. PersistentVolumes are a
|
||||
way for users to "claim" durable storage (such as a GCE PersistentDisk or an
|
||||
iSCSI volume) without knowing the details of the particular cloud environment.
|
||||
|
||||
@@ -614,9 +614,9 @@ Currently, the following types of volume sources can be projected:
|
||||
- [`downwardAPI`](#downwardapi)
|
||||
- `configMap`
|
||||
|
||||
All sources are required to be in the same namespace as the pod. For more details, see the [all-in-one volume design document](https://github.com/kubernetes/community/blob/{{< param "githubbranch" >}}/contributors/design-proposals/node/all-in-one-volume.md).
|
||||
All sources are required to be in the same namespace as the Pod. For more details, see the [all-in-one volume design document](https://github.com/kubernetes/community/blob/{{< param "githubbranch" >}}/contributors/design-proposals/node/all-in-one-volume.md).
|
||||
|
||||
#### Example pod with a secret, a downward API, and a configmap.
|
||||
#### Example Pod with a secret, a downward API, and a configmap.
|
||||
|
||||
```yaml
|
||||
apiVersion: v1
|
||||
@@ -656,7 +656,7 @@ spec:
|
||||
path: my-group/my-config
|
||||
```
|
||||
|
||||
#### Example pod with multiple secrets with a non-default permission mode set.
|
||||
#### Example Pod with multiple secrets with a non-default permission mode set.
|
||||
|
||||
```yaml
|
||||
apiVersion: v1
|
||||
@@ -698,7 +698,7 @@ parameters are nearly the same with two exceptions:
|
||||
for each individual projection.
|
||||
|
||||
{{< note >}}
|
||||
**Note:** A container using a projected volume source as a [subPath](#using-subpath) volume mount will not
|
||||
**Note:** A Container using a projected volume source as a [subPath](#using-subpath) volume mount will not
|
||||
receive updates for those volume sources.
|
||||
{{< /note >}}
|
||||
|
||||
@@ -710,8 +710,8 @@ and aggregates capacity across multiple servers. Portworx runs in-guest in virtu
|
||||
machines or on bare metal Linux nodes.
|
||||
|
||||
A `portworxVolume` can be dynamically created through Kubernetes or it can also
|
||||
be pre-provisioned and referenced inside a Kubernetes pod.
|
||||
Here is an example pod referencing a pre-provisioned PortworxVolume:
|
||||
be pre-provisioned and referenced inside a Kubernetes Pod.
|
||||
Here is an example Pod referencing a pre-provisioned PortworxVolume:
|
||||
|
||||
```yaml
|
||||
apiVersion: v1
|
||||
@@ -735,7 +735,7 @@ spec:
|
||||
|
||||
{{< caution >}}
|
||||
**Important:** Make sure you have an existing PortworxVolume with name `pxvol`
|
||||
before using it in the pod.
|
||||
before using it in the Pod.
|
||||
{{< /caution >}}
|
||||
|
||||
More details and examples can be found [here](https://github.com/kubernetes/examples/tree/{{< param "githubbranch" >}}/staging/volumes/portworx/README.md).
|
||||
@@ -743,7 +743,7 @@ More details and examples can be found [here](https://github.com/kubernetes/exam
|
||||
### quobyte
|
||||
|
||||
A `quobyte` volume allows an existing [Quobyte](http://www.quobyte.com) volume to
|
||||
be mounted into your pod.
|
||||
be mounted into your Pod.
|
||||
|
||||
{{< caution >}}
|
||||
**Important:** You must have your own Quobyte setup running with the volumes
|
||||
@@ -756,10 +756,10 @@ See the [Quobyte example](https://github.com/kubernetes/examples/tree/{{< param
|
||||
|
||||
An `rbd` volume allows a [Rados Block
|
||||
Device](http://ceph.com/docs/master/rbd/rbd/) volume to be mounted into your
|
||||
pod. Unlike `emptyDir`, which is erased when a Pod is removed, the contents of
|
||||
Pod. Unlike `emptyDir`, which is erased when a Pod is removed, the contents of
|
||||
a `rbd` volume are preserved and the volume is merely unmounted. This
|
||||
means that a RBD volume can be pre-populated with data, and that data can
|
||||
be "handed off" between pods.
|
||||
be "handed off" between Pods.
|
||||
|
||||
{{< caution >}}
|
||||
**Important:** You must have your own Ceph installation running before you can use RBD.
|
||||
@@ -767,7 +767,7 @@ be "handed off" between pods.
|
||||
|
||||
A feature of RBD is that it can be mounted as read-only by multiple consumers
|
||||
simultaneously. This means that you can pre-populate a volume with your dataset
|
||||
and then serve it in parallel from as many pods as you need. Unfortunately,
|
||||
and then serve it in parallel from as many Pods as you need. Unfortunately,
|
||||
RBD volumes can only be mounted by a single consumer in read-write mode - no
|
||||
simultaneous writers allowed.
|
||||
|
||||
@@ -777,7 +777,7 @@ See the [RBD example](https://github.com/kubernetes/examples/tree/{{< param "git
|
||||
|
||||
ScaleIO is a software-based storage platform that can use existing hardware to
|
||||
create clusters of scalable shared block networked storage. The `scaleIO` volume
|
||||
plugin allows deployed pods to access existing ScaleIO
|
||||
plugin allows deployed Pods to access existing ScaleIO
|
||||
volumes (or it can dynamically provision new volumes for persistent volume claims, see
|
||||
[ScaleIO Persistent Volumes](/docs/concepts/storage/persistent-volumes/#scaleio)).
|
||||
|
||||
@@ -786,7 +786,7 @@ volumes (or it can dynamically provision new volumes for persistent volume claim
|
||||
running with the volumes created before you can use them.
|
||||
{{< /caution >}}
|
||||
|
||||
The following is an example pod configuration with ScaleIO:
|
||||
The following is an example Pod configuration with ScaleIO:
|
||||
|
||||
```yaml
|
||||
apiVersion: v1
|
||||
@@ -818,8 +818,8 @@ For further detail, please the see the [ScaleIO examples](https://github.com/kub
|
||||
### secret
|
||||
|
||||
A `secret` volume is used to pass sensitive information, such as passwords, to
|
||||
pods. You can store secrets in the Kubernetes API and mount them as files for
|
||||
use by pods without coupling to Kubernetes directly. `secret` volumes are
|
||||
Pods. You can store secrets in the Kubernetes API and mount them as files for
|
||||
use by Pods without coupling to Kubernetes directly. `secret` volumes are
|
||||
backed by tmpfs (a RAM-backed filesystem) so they are never written to
|
||||
non-volatile storage.
|
||||
|
||||
@@ -828,7 +828,7 @@ non-volatile storage.
|
||||
{{< /caution >}}
|
||||
|
||||
{{< note >}}
|
||||
**Note:** A container using a Secret as a [subPath](#using-subpath) volume mount will not
|
||||
**Note:** A Container using a Secret as a [subPath](#using-subpath) volume mount will not
|
||||
receive Secret updates.
|
||||
{{< /note >}}
|
||||
|
||||
@@ -837,20 +837,20 @@ Secrets are described in more detail [here](/docs/user-guide/secrets).
|
||||
### storageOS
|
||||
|
||||
A `storageos` volume allows an existing [StorageOS](https://www.storageos.com)
|
||||
volume to be mounted into your pod.
|
||||
volume to be mounted into your Pod.
|
||||
|
||||
StorageOS runs as a container within your Kubernetes environment, making local
|
||||
StorageOS runs as a Container within your Kubernetes environment, making local
|
||||
or attached storage accessible from any node within the Kubernetes cluster.
|
||||
Data can be replicated to protect against node failure. Thin provisioning and
|
||||
compression can improve utilization and reduce cost.
|
||||
|
||||
At its core, StorageOS provides block storage to containers, accessible via a file system.
|
||||
At its core, StorageOS provides block storage to Containers, accessible via a file system.
|
||||
|
||||
The StorageOS container requires 64-bit Linux and has no additional dependencies.
|
||||
The StorageOS Container requires 64-bit Linux and has no additional dependencies.
|
||||
A free developer license is available.
|
||||
|
||||
{{< caution >}}
|
||||
**Important:** You must run the StorageOS container on each node that wants to
|
||||
**Important:** You must run the StorageOS Container on each node that wants to
|
||||
access StorageOS volumes or that will contribute storage capacity to the pool.
|
||||
For installation instructions, consult the
|
||||
[StorageOS documentation](https://docs.storageos.com).
|
||||
@@ -898,7 +898,7 @@ A `vsphereVolume` is used to mount a vSphere VMDK Volume into your Pod. The con
|
||||
of a volume are preserved when it is unmounted. It supports both VMFS and VSAN datastore.
|
||||
|
||||
{{< caution >}}
|
||||
**Important:** You must create VMDK using one of the following method before using with POD.
|
||||
**Important:** You must create VMDK using one of the following method before using with Pod.
|
||||
{{< /caution >}}
|
||||
|
||||
#### Creating a VMDK volume
|
||||
@@ -951,10 +951,10 @@ More examples can be found [here](https://github.com/kubernetes/examples/tree/ma
|
||||
|
||||
## Using subPath
|
||||
|
||||
Sometimes, it is useful to share one volume for multiple uses in a single pod. The `volumeMounts.subPath`
|
||||
Sometimes, it is useful to share one volume for multiple uses in a single Pod. The `volumeMounts.subPath`
|
||||
property can be used to specify a sub-path inside the referenced volume instead of its root.
|
||||
|
||||
Here is an example of a pod with a LAMP stack (Linux Apache Mysql PHP) using a single, shared volume.
|
||||
Here is an example of a Pod with a LAMP stack (Linux Apache Mysql PHP) using a single, shared volume.
|
||||
The HTML contents are mapped to its `html` folder, and the databases will be stored in its `mysql` folder:
|
||||
|
||||
```yaml
|
||||
@@ -990,8 +990,8 @@ spec:
|
||||
The storage media (Disk, SSD, etc.) of an `emptyDir` volume is determined by the
|
||||
medium of the filesystem holding the kubelet root dir (typically
|
||||
`/var/lib/kubelet`). There is no limit on how much space an `emptyDir` or
|
||||
`hostPath` volume can consume, and no isolation between containers or between
|
||||
pods.
|
||||
`hostPath` volume can consume, and no isolation between Containers or between
|
||||
Pods.
|
||||
|
||||
In the future, we expect that `emptyDir` and `hostPath` volumes will be able to
|
||||
request a certain amount of space using a [resource](/docs/user-guide/compute-resources)
|
||||
@@ -1033,8 +1033,8 @@ Once a CSI compatible volume driver is deployed on a Kubernetes cluster, users
|
||||
may use the `csi` volume type to attach, mount, etc. the volumes exposed by the
|
||||
CSI driver.
|
||||
|
||||
The `csi` volume type does not support direct reference from pod and may only be
|
||||
referenced in a pod via a `PersistentVolumeClaim` object.
|
||||
The `csi` volume type does not support direct reference from Pod and may only be
|
||||
referenced in a Pod via a `PersistentVolumeClaim` object.
|
||||
|
||||
The following fields are available to storage administrators to configure a CSI
|
||||
persistent volume:
|
||||
@@ -1055,7 +1055,7 @@ persistent volume:
|
||||
`ControllerPublishVolumeRequest`.
|
||||
- `fsType`: If the PV's `VolumeMode` is `Filesystem` then this field may be used
|
||||
to specify the filesystem that should be used to mount the volume. If the
|
||||
volume has not been formated and formating is supported, this value will be
|
||||
volume has not been formatted and formating is supported, this value will be
|
||||
used to format the volume. If a value is not specified, `ext4` is assumed.
|
||||
This value is passed to the CSI driver via the `VolumeCapability` field of
|
||||
`ControllerPublishVolumeRequest`, `NodeStageVolumeRequest`, and
|
||||
@@ -1122,7 +1122,7 @@ Its values are:
|
||||
In other words, if the host mounts anything inside the volume mount, the
|
||||
Container will see it mounted there.
|
||||
|
||||
Similarly, if any pod with `Bidirectional` mount propagation to the same
|
||||
Similarly, if any Pod with `Bidirectional` mount propagation to the same
|
||||
volume mounts anything there, the Container with `HostToContainer` mount
|
||||
propagation will see it.
|
||||
|
||||
|
||||
Reference in New Issue
Block a user