Merge pull request #22990 from thaJeztah/docs-cherry-picks
Docs cherry picks (2016-05-25)
This commit is contained in:
Sven Dowideit
commit
d544b3ee99
19 changed files with 252 additions and 165 deletions
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@ -1,17 +1,8 @@
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FROM docs/base:latest
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FROM docs/base:oss
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MAINTAINER Mary Anthony <mary@docker.com> (@moxiegirl)
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RUN svn checkout https://github.com/docker/compose/trunk/docs /docs/content/compose
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RUN svn checkout https://github.com/docker/swarm/trunk/docs /docs/content/swarm
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RUN svn checkout https://github.com/docker/machine/trunk/docs /docs/content/machine
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RUN svn checkout https://github.com/docker/distribution/trunk/docs /docs/content/registry
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RUN svn checkout https://github.com/docker/notary/trunk/docs /docs/content/notary
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RUN svn checkout https://github.com/docker/kitematic/trunk/docs /docs/content/kitematic
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RUN svn checkout https://github.com/docker/toolbox/trunk/docs /docs/content/toolbox
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RUN svn checkout https://github.com/docker/opensource/trunk/docs /docs/content/opensource
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ENV PROJECT=engine
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# To get the git info for this repo
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COPY . /src
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RUN rm -r /docs/content/$PROJECT/
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COPY . /docs/content/$PROJECT/
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@ -24,9 +24,8 @@ HUGO_BASE_URL=$(shell test -z "$(DOCKER_IP)" && echo localhost || echo "$(DOCKER
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HUGO_BIND_IP=0.0.0.0
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GIT_BRANCH := $(shell git rev-parse --abbrev-ref HEAD 2>/dev/null)
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DOCKER_IMAGE := docker$(if $(GIT_BRANCH),:$(GIT_BRANCH))
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DOCKER_DOCS_IMAGE := docs-base$(if $(GIT_BRANCH),:$(GIT_BRANCH))
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GIT_BRANCH_CLEAN := $(shell echo $(GIT_BRANCH) | sed -e "s/[^[:alnum:]]/-/g")
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DOCKER_DOCS_IMAGE := docker-docs$(if $(GIT_BRANCH_CLEAN),:$(GIT_BRANCH_CLEAN))
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DOCKER_RUN_DOCS := docker run --rm -it $(DOCS_MOUNT) -e AWS_S3_BUCKET -e NOCACHE
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@ -84,10 +84,9 @@ Because of which, the driver specific log tag options `syslog-tag`, `gelf-tag` a
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### LXC built-in exec driver
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**Deprecated In Release: v1.8**
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**Target For Removal In Release: v1.10**
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**Removed In Release: v1.10**
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The built-in LXC execution driver is deprecated for an external implementation.
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The lxc-conf flag and API fields will also be removed.
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The built-in LXC execution driver, the lxc-conf flag, and API fields have been removed.
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### Old Command Line Options
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**Deprecated In Release: [v1.8.0](https://github.com/docker/docker/releases/tag/v1.8.0)**
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@ -60,7 +60,7 @@ Plugin
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[Keywhiz plugin](https://github.com/calavera/docker-volume-keywhiz) | A plugin that provides credentials and secret management using Keywhiz as a central repository.
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[Local Persist Plugin](https://github.com/CWSpear/local-persist) | A volume plugin that extends the default `local` driver's functionality by allowing you specify a mountpoint anywhere on the host, which enables the files to *always persist*, even if the volume is removed via `docker volume rm`.
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[NetApp Plugin](https://github.com/NetApp/netappdvp) (nDVP) | A volume plugin that provides direct integration with the Docker ecosystem for the NetApp storage portfolio. The nDVP package supports the provisioning and management of storage resources from the storage platform to Docker hosts, with a robust framework for adding additional platforms in the future.
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[Netshare plugin](https://github.com/gondor/docker-volume-netshare) | A volume plugin that provides volume management for NFS 3/4, AWS EFS and CIFS file systems.
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[Netshare plugin](https://github.com/ContainX/docker-volume-netshare) | A volume plugin that provides volume management for NFS 3/4, AWS EFS and CIFS file systems.
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[OpenStorage Plugin](https://github.com/libopenstorage/openstorage) | A cluster-aware volume plugin that provides volume management for file and block storage solutions. It implements a vendor neutral specification for implementing extensions such as CoS, encryption, and snapshots. It has example drivers based on FUSE, NFS, NBD and EBS to name a few.
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[Quobyte Volume Plugin](https://github.com/quobyte/docker-volume) | A volume plugin that connects Docker to [Quobyte](http://www.quobyte.com/containers)'s data center file system, a general-purpose scalable and fault-tolerant storage platform.
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[REX-Ray plugin](https://github.com/emccode/rexray) | A volume plugin which is written in Go and provides advanced storage functionality for many platforms including VirtualBox, EC2, Google Compute Engine, OpenStack, and EMC.
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@ -186,7 +186,7 @@ You can uninstall the Docker software with `dnf`.
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1. List the package you have installed.
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$ dnf list installed | grep docker dnf list installed | grep docker
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$ dnf list installed | grep docker
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docker-engine.x86_64 1.7.1-0.1.fc21 @/docker-engine-1.7.1-0.1.fc21.el7.x86_64
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2. Remove the package.
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|
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@ -361,7 +361,16 @@ RUN /bin/bash -c 'source $HOME/.bashrc ; echo $HOME'
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> This means that normal shell processing does not happen. For example,
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> `RUN [ "echo", "$HOME" ]` will not do variable substitution on `$HOME`.
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> If you want shell processing then either use the *shell* form or execute
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> a shell directly, for example: `RUN [ "sh", "-c", "echo", "$HOME" ]`.
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> a shell directly, for example: `RUN [ "sh", "-c", "echo $HOME" ]`.
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>
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> **Note**:
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> In the *JSON* form, it is necessary to escape backslashes. This is
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> particularly relevant on Windows where the backslash is the path seperator.
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> The following line would otherwise be treated as *shell* form due to not
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> being valid JSON, and fail in an unexpected way:
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> `RUN ["c:\windows\system32\tasklist.exe"]`
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> The correct syntax for this example is:
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> `RUN ["c:\\windows\\system32\\tasklist.exe"]`
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The cache for `RUN` instructions isn't invalidated automatically during
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the next build. The cache for an instruction like
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|
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@ -28,7 +28,7 @@ detached process.
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To stop a container, use `CTRL-c`. This key sequence sends `SIGKILL` to the
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container. If `--sig-proxy` is true (the default),`CTRL-c` sends a `SIGINT` to
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the container. You can detach from a container and leave it running using the
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using `CTRL-p CTRL-q` key sequence.
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`CTRL-p CTRL-q` key sequence.
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> **Note:**
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> A process running as PID 1 inside a container is treated specially by
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@ -298,6 +298,9 @@ accessed like regular environment variables in the `RUN` instruction of the
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Dockerfile. Also, these values don't persist in the intermediate or final images
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like `ENV` values do.
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Using this flag will not alter the output you see when the `ARG` lines from the
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Dockerfile are echoed during the build process.
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For detailed information on using `ARG` and `ENV` instructions, see the
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[Dockerfile reference](../builder.md).
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@ -81,7 +81,17 @@ you must be explicit with a relative or absolute path, for example:
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`/path/to/file:name.txt` or `./file:name.txt`
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It is not possible to copy certain system files such as resources under
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`/proc`, `/sys`, `/dev`, and mounts created by the user in the container.
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`/proc`, `/sys`, `/dev`, [tmpfs](run.md#mount-tmpfs-tmpfs), and mounts created by
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the user in the container. However, you can still copy such files by manually
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running `tar` in `docker exec`. For example (consider `SRC_PATH` and `DEST_PATH`
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are directories):
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$ docker exec foo tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | tar Cxf DEST_PATH -
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or
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$ tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | docker exec -i foo tar Cxf DEST_PATH -
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Using `-` as the `SRC_PATH` streams the contents of `STDIN` as a tar archive.
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The command extracts the content of the tar to the `DEST_PATH` in container's
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@ -27,6 +27,15 @@ can `pull` and try without needing to define and configure your own.
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To download a particular image, or set of images (i.e., a repository),
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use `docker pull`.
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## Proxy configuration
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If you are behind a HTTP proxy server, for example in corporate settings,
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before open a connect to registry, you may need to configure the Docker
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daemon's proxy settings, using the `HTTP_PROXY`, `HTTPS_PROXY`, and `NO_PROXY`
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environment variables. To set these environment variables on a host using
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`systemd`, refer to the [control and configure Docker with systemd](../../admin/systemd.md#http-proxy)
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for variables configuration.
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## Examples
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|
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### Pull an image from Docker Hub
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|
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@ -227,12 +227,12 @@ system's interfaces.
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This sets simple (non-array) environmental variables in the container. For
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illustration all three
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flags are shown here. Where `-e`, `--env` take an environment variable and
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value, or if no `=` is provided, then that variable's current value is passed
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through (i.e. `$MYVAR1` from the host is set to `$MYVAR1` in the container).
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When no `=` is provided and that variable is not defined in the client's
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environment then that variable will be removed from the container's list of
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environment variables.
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All three flags, `-e`, `--env` and `--env-file` can be repeated.
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value, or if no `=` is provided, then that variable's current value, set via
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`export`, is passed through (i.e. `$MYVAR1` from the host is set to `$MYVAR1`
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in the container). When no `=` is provided and that variable is not defined
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in the client's environment then that variable will be removed from the
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container's list of environment variables. All three flags, `-e`, `--env` and
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`--env-file` can be repeated.
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Regardless of the order of these three flags, the `--env-file` are processed
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first, and then `-e`, `--env` flags. This way, the `-e` or `--env` will
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|
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@ -612,15 +612,12 @@ with the same logic -- if the original volume was specified with a name it will
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||||
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||||
You can override the default labeling scheme for each container by specifying
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the `--security-opt` flag. For example, you can specify the MCS/MLS level, a
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requirement for MLS systems. Specifying the level in the following command
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the `--security-opt` flag. Specifying the level in the following command
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allows you to share the same content between containers.
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$ docker run --security-opt label=level:s0:c100,c200 -it fedora bash
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An MLS example might be:
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$ docker run --security-opt label=level:TopSecret -it rhel7 bash
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> **Note**: Automatic translation of MLS labels is not currently supported.
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To disable the security labeling for this container versus running with the
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`--permissive` flag, use the following command:
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@ -1433,7 +1430,7 @@ The `host-src` can either be an absolute path or a `name` value. If you
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supply an absolute path for the `host-dir`, Docker bind-mounts to the path
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you specify. If you supply a `name`, Docker creates a named volume by that `name`.
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A `name` value must start with start with an alphanumeric character,
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A `name` value must start with an alphanumeric character,
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followed by `a-z0-9`, `_` (underscore), `.` (period) or `-` (hyphen).
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An absolute path starts with a `/` (forward slash).
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||||
|
|
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@ -22,7 +22,7 @@ times but with different values, newer labels overwrite previous labels. Docker
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|||
uses the last `key=value` you supply.
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||||
>**Note:** Support for daemon-labels was added in Docker 1.4.1. Labels on
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>containers and images are new in Docker 1.6.0
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>containers and images were added in Docker 1.6.0
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||||
|
||||
## Label keys (namespaces)
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||||
|
|
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@ -57,7 +57,7 @@ docker0 Link encap:Ethernet HWaddr 02:42:47:bc:3a:eb
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RX bytes:1100 (1.1 KB) TX bytes:648 (648.0 B)
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```
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|
||||
The `none` network adds a container to a container-specific network stack. That container lacks a network interface. Attaching to such a container and looking at it's stack you see this:
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The `none` network adds a container to a container-specific network stack. That container lacks a network interface. Attaching to such a container and looking at its stack you see this:
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||||
|
||||
```
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$ docker attach nonenetcontainer
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|
|
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|||
|
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@ -289,7 +289,7 @@ examine its networking stack:
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|||
$ docker attach container2
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||||
```
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||||
|
||||
If you look a the container's network stack you should see two Ethernet interfaces, one for the default bridge network and one for the `isolated_nw` network.
|
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If you look at the container's network stack you should see two Ethernet interfaces, one for the default bridge network and one for the `isolated_nw` network.
|
||||
|
||||
```bash
|
||||
/ # ifconfig
|
||||
|
|
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|
|
@ -212,7 +212,7 @@ a `direct-lvm` configuration.
|
|||
> and have images you want to keep, `push` them Docker Hub or your private
|
||||
> Docker Trusted Registry before attempting this procedure.
|
||||
|
||||
The procedure below will create a 90GB data volume and 4GB metadata volume to
|
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The procedure below will create a logical volume configured as a thin pool to
|
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use as backing for the storage pool. It assumes that you have a spare block
|
||||
device at `/dev/xvdf` with enough free space to complete the task. The device
|
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identifier and volume sizes may be be different in your environment and you
|
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|
|
@ -221,106 +221,146 @@ assumes that the Docker daemon is in the `stopped` state.
|
|||
|
||||
1. Log in to the Docker host you want to configure and stop the Docker daemon.
|
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|
||||
2. If it exists, delete your existing image store by removing the
|
||||
`/var/lib/docker` directory.
|
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2. Install the LVM2 package.
|
||||
The LVM2 package includes the userspace toolset that provides logical volume
|
||||
management facilities on linux.
|
||||
|
||||
3. Create a physical volume replacing `/dev/xvdf` with your block device.
|
||||
|
||||
```bash
|
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$ sudo rm -rf /var/lib/docker
|
||||
$ pvcreate /dev/xvdf
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```
|
||||
|
||||
3. Create an LVM physical volume (PV) on your spare block device using the
|
||||
`pvcreate` command.
|
||||
4. Create a 'docker' volume group.
|
||||
|
||||
```bash
|
||||
$ sudo pvcreate /dev/xvdf
|
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Physical volume `/dev/xvdf` successfully created
|
||||
$ vgcreate docker /dev/xvdf
|
||||
```
|
||||
|
||||
The device identifier may be different on your system. Remember to substitute
|
||||
your value in the command above. If your host is running on AWS EC2, you may
|
||||
need to install `lvm2` and <a href="http://goo.gl/Q5pUwG"
|
||||
target="_blank">attach an EBS device</a> to use this procedure.
|
||||
5. Create a thin pool named `thinpool`.
|
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|
||||
4. Create a new volume group (VG) called `vg-docker` using the PV created in
|
||||
the previous step.
|
||||
In this example, the data logical is 95% of the 'docker' volume group size.
|
||||
Leaving this free space allows for auto expanding of either the data or
|
||||
metadata if space runs low as a temporary stopgap.
|
||||
|
||||
```bash
|
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$ sudo vgcreate vg-docker /dev/xvdf
|
||||
Volume group `vg-docker` successfully created
|
||||
$ lvcreate --wipesignatures y -n thinpool docker -l 95%VG
|
||||
$ lvcreate --wipesignatures y -n thinpoolmeta docker -l 1%VG
|
||||
```
|
||||
|
||||
5. Create a new 90GB logical volume (LV) called `data` from space in the
|
||||
`vg-docker` volume group.
|
||||
6. Convert the pool to a thin pool.
|
||||
|
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```bash
|
||||
$ sudo lvcreate -L 90G -n data vg-docker
|
||||
Logical volume `data` created.
|
||||
$ lvconvert -y --zero n -c 512K --thinpool docker/thinpool --poolmetadata docker/thinpoolmeta
|
||||
```
|
||||
|
||||
The command creates an LVM logical volume called `data` and an associated
|
||||
block device file at `/dev/vg-docker/data`. In a later step, you instruct the
|
||||
`devicemapper` storage driver to use this block device to store image and
|
||||
container data.
|
||||
|
||||
If you receive a signature detection warning, make sure you are working on
|
||||
the correct devices before continuing. Signature warnings indicate that the
|
||||
device you're working on is currently in use by LVM or has been used by LVM in
|
||||
the past.
|
||||
|
||||
6. Create a new logical volume (LV) called `metadata` from space in the
|
||||
`vg-docker` volume group.
|
||||
7. Configure autoextension of thin pools via an `lvm` profile.
|
||||
|
||||
```bash
|
||||
$ sudo lvcreate -L 4G -n metadata vg-docker
|
||||
Logical volume `metadata` created.
|
||||
$ vi /etc/lvm/profile/docker-thinpool.profile
|
||||
```
|
||||
|
||||
This creates an LVM logical volume called `metadata` and an associated
|
||||
block device file at `/dev/vg-docker/metadata`. In the next step you instruct
|
||||
the `devicemapper` storage driver to use this block device to store image and
|
||||
container metadata.
|
||||
8. Specify 'thin_pool_autoextend_threshold' value.
|
||||
|
||||
7. Start the Docker daemon with the `devicemapper` storage driver and the
|
||||
`--storage-opt` flags.
|
||||
The value should be the percentage of space used before `lvm` attempts
|
||||
to autoextend the available space (100 = disabled).
|
||||
|
||||
The `data` and `metadata` devices that you pass to the `--storage-opt`
|
||||
options were created in the previous steps.
|
||||
```
|
||||
thin_pool_autoextend_threshold = 80
|
||||
```
|
||||
|
||||
9. Modify the `thin_pool_autoextend_percent` for when thin pool autoextension occurs.
|
||||
|
||||
The value's setting is the perentage of space to increase the thin pool (100 =
|
||||
disabled)
|
||||
|
||||
```
|
||||
thin_pool_autoextend_percent = 20
|
||||
```
|
||||
|
||||
10. Check your work, your `docker-thinpool.profile` file should appear similar to the following:
|
||||
|
||||
An example `/etc/lvm/profile/docker-thinpool.profile` file:
|
||||
|
||||
```
|
||||
activation {
|
||||
thin_pool_autoextend_threshold=80
|
||||
thin_pool_autoextend_percent=20
|
||||
}
|
||||
```
|
||||
|
||||
11. Apply your new lvm profile
|
||||
|
||||
```bash
|
||||
$ sudo docker daemon --storage-driver=devicemapper --storage-opt dm.datadev=/dev/vg-docker/data --storage-opt dm.metadatadev=/dev/vg-docker/metadata &
|
||||
[1] 2163
|
||||
[root@ip-10-0-0-75 centos]# INFO[0000] Listening for HTTP on unix (/var/run/docker.sock)
|
||||
INFO[0027] Option DefaultDriver: bridge
|
||||
INFO[0027] Option DefaultNetwork: bridge
|
||||
<-- output truncated -->
|
||||
INFO[0027] Daemon has completed initialization
|
||||
INFO[0027] Docker daemon commit=1b09a95 graphdriver=aufs version=1.11.0-dev
|
||||
$ lvchange --metadataprofile docker-thinpool docker/thinpool
|
||||
```
|
||||
|
||||
It is also possible to set the `--storage-driver` and `--storage-opt` flags
|
||||
in the Docker config file and start the daemon normally using the `service` or
|
||||
`systemd` commands.
|
||||
|
||||
8. Use the `docker info` command to verify that the daemon is using `data` and
|
||||
`metadata` devices you created.
|
||||
12. Verify the `lv` is monitored.
|
||||
|
||||
```bash
|
||||
$ sudo docker info
|
||||
INFO[0180] GET /v1.20/info
|
||||
Containers: 0
|
||||
Images: 0
|
||||
Storage Driver: devicemapper
|
||||
Pool Name: docker-202:1-1032-pool
|
||||
Pool Blocksize: 65.54 kB
|
||||
Backing Filesystem: xfs
|
||||
Data file: /dev/vg-docker/data
|
||||
Metadata file: /dev/vg-docker/metadata
|
||||
[...]
|
||||
$ lvs -o+seg_monitor
|
||||
```
|
||||
|
||||
The output of the command above shows the storage driver as `devicemapper`.
|
||||
The last two lines also confirm that the correct devices are being used for
|
||||
the `Data file` and the `Metadata file`.
|
||||
13. If the Docker daemon was previously started, clear your graph driver directory.
|
||||
|
||||
Clearing your graph driver removes any images, containers, and volumes in your
|
||||
Docker installation.
|
||||
|
||||
```bash
|
||||
$ rm -rf /var/lib/docker/*
|
||||
```
|
||||
|
||||
14. Configure the Docker daemon with specific devicemapper options.
|
||||
|
||||
There are two ways to do this. You can set options on the commmand line if you start the daemon there:
|
||||
|
||||
```bash
|
||||
--storage-driver=devicemapper --storage-opt=dm.thinpooldev=/dev/mapper/docker-thinpool --storage-opt dm.use_deferred_removal=true
|
||||
```
|
||||
|
||||
You can also set them for startup in the `daemon.json` configuration, for example:
|
||||
|
||||
```json
|
||||
{
|
||||
"storage-driver": "devicemapper",
|
||||
"storage-opts": [
|
||||
"dm.thinpooldev=/dev/mapper/docker-thinpool",
|
||||
"dm.use_deferred_removal=true"
|
||||
]
|
||||
}
|
||||
```
|
||||
|
||||
15. If using systemd and modifying the daemon configuration via unit or drop-in file, reload systemd to scan for changes.
|
||||
|
||||
```bash
|
||||
$ systemctl daemon-reload
|
||||
```
|
||||
|
||||
16. Start the Docker daemon.
|
||||
|
||||
```bash
|
||||
$ systemctl start docker
|
||||
```
|
||||
|
||||
After you start the Docker daemon, ensure you monitor your thin pool and volume
|
||||
group free space. While the volume group will auto-extend, it can still fill
|
||||
up. To monitor logical volumes, use `lvs` without options or `lvs -a` to see tha
|
||||
data and metadata sizes. To monitor volume group free space, use the `vgs` command.
|
||||
|
||||
Logs can show the auto-extension of the thin pool when it hits the threshold, to
|
||||
view the logs use:
|
||||
|
||||
```bash
|
||||
$ journalctl -fu dm-event.service
|
||||
```
|
||||
|
||||
If you run into repeated problems with thin pool, you can use the
|
||||
`dm.min_free_space` option to tune the Engine behavior. This value ensures that
|
||||
operations fail with a warning when the free space is at or near the minimum.
|
||||
For information, see <a
|
||||
href="../../../reference/commandline/daemon/#storage-driver-options"
|
||||
target="_blank">the storage driver options in the Engine daemon reference</a>.
|
||||
|
||||
|
||||
### Examine devicemapper structures on the host
|
||||
|
||||
|
|
@ -342,7 +382,7 @@ xvdf 202:80 0 10G 0 disk
|
|||
The diagram below shows the image from prior examples updated with the detail
|
||||
from the `lsblk` command above.
|
||||
|
||||
|
||||
|
||||
|
||||
In the diagram, the pool is named `Docker-202:1-1032-pool` and spans the `data`
|
||||
and `metadata` devices created earlier. The `devicemapper` constructs the pool
|
||||
|
|
@ -371,7 +411,8 @@ capacity.
|
|||
|
||||
### For a loop-lvm configuration
|
||||
|
||||
In this scenario, the thin pool is configured to use `loop-lvm` mode. To show the specifics of the existing configuration use `docker info`:
|
||||
In this scenario, the thin pool is configured to use `loop-lvm` mode. To show
|
||||
the specifics of the existing configuration use `docker info`:
|
||||
|
||||
```bash
|
||||
$ sudo docker info
|
||||
|
|
@ -426,12 +467,10 @@ The `Data Space` values show that the pool is 100GB total. This example extends
|
|||
3. Verify the file size changed.
|
||||
|
||||
```bash
|
||||
$ sudo ls -al /var/lib/docker/devicemapper/devicemapper/
|
||||
total 1175492
|
||||
drwx------ 2 root root 4096 Mar 29 02:45 .
|
||||
drwx------ 5 root root 4096 Mar 29 02:48 ..
|
||||
-rw------- 1 root root 214748364800 Mar 31 11:20 data
|
||||
-rw------- 1 root root 2147483648 Mar 31 11:17 metadata
|
||||
$ sudo ls -lh /var/lib/docker/devicemapper/devicemapper/
|
||||
total 1.2G
|
||||
-rw------- 1 root root 200G Apr 14 08:47 data
|
||||
-rw------- 1 root root 2.0G Apr 19 13:27 metadata
|
||||
```
|
||||
|
||||
4. Reload data loop device
|
||||
|
|
@ -448,23 +487,35 @@ The `Data Space` values show that the pool is 100GB total. This example extends
|
|||
|
||||
a. Get the pool name first.
|
||||
|
||||
$ sudo dmsetup status docker-8:1-123141-pool: 0 209715200 thin-pool 91
|
||||
```bash
|
||||
$ sudo dmsetup status | grep pool
|
||||
docker-8:1-123141-pool: 0 209715200 thin-pool 91
|
||||
422/524288 18338/1638400 - rw discard_passdown queue_if_no_space -
|
||||
```
|
||||
|
||||
The name is the string before the colon.
|
||||
|
||||
b. Dump the device mapper table first.
|
||||
|
||||
```bash
|
||||
$ sudo dmsetup table docker-8:1-123141-pool
|
||||
0 209715200 thin-pool 7:1 7:0 128 32768 1 skip_block_zeroing
|
||||
```
|
||||
|
||||
c. Calculate the real total sectors of the thin pool now.
|
||||
|
||||
Change the second number of the table info (i.e. the disk end sector) to reflect the new number of 512 byte sectors in the disk. For example, as the new loop size is 200GB, change the second number to 419430400.
|
||||
Change the second number of the table info (i.e. the disk end sector) to
|
||||
reflect the new number of 512 byte sectors in the disk. For example, as the
|
||||
new loop size is 200GB, change the second number to 419430400.
|
||||
|
||||
|
||||
d. Reload the thin pool with the new sector number
|
||||
|
||||
$ sudo dmsetup suspend docker-8:1-123141-pool && sudo dmsetup reload docker-8:1-123141-pool --table '0 419430400 thin-pool 7:1 7:0 128 32768 1 skip_block_zeroing' && sudo dmsetup resume docker-8:1-123141-pool
|
||||
```bash
|
||||
$ sudo dmsetup suspend docker-8:1-123141-pool \
|
||||
&& sudo dmsetup reload docker-8:1-123141-pool --table '0 419430400 thin-pool 7:1 7:0 128 32768 1 skip_block_zeroing' \
|
||||
&& sudo dmsetup resume docker-8:1-123141-pool
|
||||
```
|
||||
|
||||
#### The device_tool
|
||||
|
||||
|
|
@ -506,29 +557,39 @@ disk partition.
|
|||
|
||||
a. Get the pool name.
|
||||
|
||||
```bash
|
||||
$ sudo dmsetup status | grep pool
|
||||
docker-253:17-1835016-pool: 0 96460800 thin-pool 51593 6270/1048576 701943/753600 - rw no_discard_passdown queue_if_no_space
|
||||
```
|
||||
|
||||
The name is the string before the colon.
|
||||
|
||||
b. Dump the device mapper table.
|
||||
|
||||
```bash
|
||||
$ sudo dmsetup table docker-253:17-1835016-pool
|
||||
0 96460800 thin-pool 252:0 252:1 128 32768 1 skip_block_zeroing
|
||||
```
|
||||
|
||||
c. Calculate the real total sectors of the thin pool now. we can use `blockdev` to get the real size of data lv.
|
||||
|
||||
Change the second number of the table info (i.e. the disk end sector) to
|
||||
Change the second number of the table info (i.e. the number of sectors) to
|
||||
reflect the new number of 512 byte sectors in the disk. For example, as the
|
||||
new data `lv` size is `264132100096` bytes, change the second number to
|
||||
`515883008`.
|
||||
|
||||
```bash
|
||||
$ sudo blockdev --getsize64 /dev/vg-docker/data
|
||||
264132100096
|
||||
```
|
||||
|
||||
d. Then reload the thin pool with the new sector number.
|
||||
|
||||
$ sudo dmsetup suspend docker-253:17-1835016-pool && sudo dmsetup reload docker-253:17-1835016-pool --table '0 515883008 thin-pool 252:0 252:1 128 32768 1 skip_block_zeroing' && sudo dmsetup resume docker-253:17-1835016-pool
|
||||
```bash
|
||||
$ sudo dmsetup suspend docker-253:17-1835016-pool \
|
||||
&& sudo dmsetup reload docker-253:17-1835016-pool --table '0 515883008 thin-pool 252:0 252:1 128 32768 1 skip_block_zeroing' \
|
||||
&& sudo dmsetup resume docker-253:17-1835016-pool
|
||||
```
|
||||
|
||||
## Device Mapper and Docker performance
|
||||
|
||||
|
|
@ -570,20 +631,20 @@ There are several other things that impact the performance of the
|
|||
`devicemapper` storage driver.
|
||||
|
||||
- **The mode.** The default mode for Docker running the `devicemapper` storage
|
||||
driver is `loop-lvm`. This mode uses sparse files and suffers from poor
|
||||
performance. It is **not recommended for production**. The recommended mode for
|
||||
driver is `loop-lvm`. This mode uses sparse files and suffers from poor
|
||||
performance. It is **not recommended for production**. The recommended mode for
|
||||
production environments is `direct-lvm` where the storage driver writes
|
||||
directly to raw block devices.
|
||||
directly to raw block devices.
|
||||
|
||||
- **High speed storage.** For best performance you should place the `Data file`
|
||||
and `Metadata file` on high speed storage such as SSD. This can be direct
|
||||
attached storage or from a SAN or NAS array.
|
||||
attached storage or from a SAN or NAS array.
|
||||
|
||||
- **Memory usage.** `devicemapper` is not the most memory efficient Docker
|
||||
storage driver. Launching *n* copies of the same container loads *n* copies of
|
||||
its files into memory. This can have a memory impact on your Docker host. As a
|
||||
result, the `devicemapper` storage driver may not be the best choice for PaaS
|
||||
and other high density use cases.
|
||||
storage driver. Launching *n* copies of the same container loads *n* copies of
|
||||
its files into memory. This can have a memory impact on your Docker host. As a
|
||||
result, the `devicemapper` storage driver may not be the best choice for PaaS
|
||||
and other high density use cases.
|
||||
|
||||
One final point, data volumes provide the best and most predictable
|
||||
performance. This is because they bypass the storage driver and do not incur
|
||||
|
|
|
|||
BIN
docs/userguide/storagedriver/images/lsblk-diagram.jpg
Normal file
BIN
docs/userguide/storagedriver/images/lsblk-diagram.jpg
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 93 KiB |
|
|
@ -40,10 +40,10 @@ driver names:
|
|||
|AUFS |`aufs` |
|
||||
|Btrfs |`btrfs` |
|
||||
|Device Mapper |`devicemapper` |
|
||||
|VFS* |`vfs` |
|
||||
|VFS |`vfs` |
|
||||
|ZFS |`zfs` |
|
||||
|
||||
To find out which storage driver is set on the daemon , you use the
|
||||
To find out which storage driver is set on the daemon, you use the
|
||||
`docker info` command:
|
||||
|
||||
$ docker info
|
||||
|
|
@ -71,18 +71,18 @@ For example, the `btrfs` storage driver on a Btrfs backing filesystem. The
|
|||
following table lists each storage driver and whether it must match the host's
|
||||
backing file system:
|
||||
|
||||
|Storage driver |Must match backing filesystem |Incompatible with |
|
||||
|---------------|------------------------------|--------------------|
|
||||
|`overlay` |No |`btrfs` `aufs` `zfs`|
|
||||
|`aufs` |No |`btrfs` `aufs` |
|
||||
|`btrfs` |Yes | N/A |
|
||||
|`devicemapper` |No | N/A |
|
||||
|`vfs` |No | N/A |
|
||||
|`zfs` |Yes | N/A |
|
||||
|Storage driver |Commonly used on |Disabled on |
|
||||
|---------------|-----------------|------------------------------|
|
||||
|`overlay` |`ext4` `xfs` |`btrfs` `aufs` `overlay` `zfs`|
|
||||
|`aufs` |`ext4` `xfs` |`btrfs` `aufs` |
|
||||
|`btrfs` |`btrfs` _only_ | N/A |
|
||||
|`devicemapper` |`direct-lvm` | N/A |
|
||||
|`vfs` |debugging only | N/A |
|
||||
|`zfs` |`zfs` _only_ | N/A |
|
||||
|
||||
|
||||
> **Note**
|
||||
> Incompatible with means some storage drivers can not run over certain backing
|
||||
> "Disabled on" means some storage drivers can not run over certain backing
|
||||
> filesystem.
|
||||
|
||||
You can set the storage driver by passing the `--storage-driver=<name>` option
|
||||
|
|
|
|||
|
|
@ -78,7 +78,16 @@ you must be explicit with a relative or absolute path, for example:
|
|||
`/path/to/file:name.txt` or `./file:name.txt`
|
||||
|
||||
It is not possible to copy certain system files such as resources under
|
||||
`/proc`, `/sys`, `/dev`, and mounts created by the user in the container.
|
||||
`/proc`, `/sys`, `/dev`, tmpfs, and mounts created by the user in the container.
|
||||
However, you can still copy such files by manually running `tar` in `docker exec`.
|
||||
For example (consider `SRC_PATH` and `DEST_PATH` are directories):
|
||||
|
||||
$ docker exec foo tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | tar Cxf DEST_PATH -
|
||||
|
||||
or
|
||||
|
||||
$ tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | docker exec -i foo tar Cxf DEST_PATH -
|
||||
|
||||
|
||||
Using `-` as the `SRC_PATH` streams the contents of `STDIN` as a tar archive.
|
||||
The command extracts the content of the tar to the `DEST_PATH` in container's
|
||||
|
|
|
|||
Loading…
Reference in a new issue