% DOCKER(1) Docker User Manuals % Docker Community % JUNE 2014
docker-cp - Copy files/folders between a container and the local filesystem.
docker cp [--help] CONTAINER:SRC_PATH DEST_PATH|-
docker cp [--help] SRC_PATH|- CONTAINER:DEST_PATH
The docker cp
utility copies the contents of SRC_PATH
to the DEST_PATH
. You can copy from the container's file system to the local machine or the reverse, from the local filesystem to the container. If -
is specified for either the SRC_PATH
or DEST_PATH
, you can also stream a tar archive from STDIN
or to STDOUT
. The CONTAINER
can be a running or stopped container. The SRC_PATH
or DEST_PATH
can be a file or directory.
The docker cp
command assumes container paths are relative to the container‘s /
(root) directory. This means supplying the initial forward slash is optional; The command sees compassionate_darwin:/tmp/foo/myfile.txt
and compassionate_darwin:tmp/foo/myfile.txt
as identical. Local machine paths can be an absolute or relative value. The command interprets a local machine’s relative paths as relative to the current working directory where docker cp
is run.
The cp
command behaves like the Unix cp -a
command in that directories are copied recursively with permissions preserved if possible. Ownership is set to the user and primary group at the destination. For example, files copied to a container are created with UID:GID
of the root user. Files copied to the local machine are created with the UID:GID
of the user which invoked the docker cp
command. If you specify the -L
option, docker cp
follows any symbolic link in the SRC_PATH
. docker cp
does not create parent directories for DEST_PATH
if they do not exist.
Assuming a path separator of /
, a first argument of SRC_PATH
and second argument of DEST_PATH
, the behavior is as follows:
SRC_PATH
specifies a fileDEST_PATH
does not existDEST_PATH
DEST_PATH
does not exist and ends with /
DEST_PATH
exists and is a fileDEST_PATH
exists and is a directorySRC_PATH
SRC_PATH
specifies a directoryDEST_PATH
does not existDEST_PATH
is created as a directory and the contents of the source directory are copied into this directoryDEST_PATH
exists and is a fileDEST_PATH
exists and is a directorySRC_PATH
does not end with /.
SRC_PATH
does end with /.
The command requires SRC_PATH
and DEST_PATH
to exist according to the above rules. If SRC_PATH
is local and is a symbolic link, the symbolic link, not the target, is copied by default. To copy the link target and not the link, specify the -L
option.
A colon (:
) is used as a delimiter between CONTAINER
and its path. You can also use :
when specifying paths to a SRC_PATH
or DEST_PATH
on a local machine, for example file:name.txt
. If you use a :
in a local machine path, 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
, 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 filesystem. In this case, DEST_PATH
must specify a directory. Using -
as the DEST_PATH
streams the contents of the resource as a tar archive to STDOUT
.
-L, --follow-link=true|false Follow symbol link in SRC_PATH
--help Print usage statement
Suppose a container has finished producing some output as a file it saves to somewhere in its filesystem. This could be the output of a build job or some other computation. You can copy these outputs from the container to a location on your local host.
If you want to copy the /tmp/foo
directory from a container to the existing /tmp
directory on your host. If you run docker cp
in your ~
(home) directory on the local host:
$ docker cp compassionate_darwin:tmp/foo /tmp
Docker creates a /tmp/foo
directory on your host. Alternatively, you can omit the leading slash in the command. If you execute this command from your home directory:
$ docker cp compassionate_darwin:tmp/foo tmp
If ~/tmp
does not exist, Docker will create it and copy the contents of /tmp/foo
from the container into this new directory. If ~/tmp
already exists as a directory, then Docker will copy the contents of /tmp/foo
from the container into a directory at ~/tmp/foo
.
When copying a single file to an existing LOCALPATH
, the docker cp
command will either overwrite the contents of LOCALPATH
if it is a file or place it into LOCALPATH
if it is a directory, overwriting an existing file of the same name if one exists. For example, this command:
$ docker cp sharp_ptolemy:/tmp/foo/myfile.txt /test
If /test
does not exist on the local machine, it will be created as a file with the contents of /tmp/foo/myfile.txt
from the container. If /test
exists as a file, it will be overwritten. Lastly, if /test
exists as a directory, the file will be copied to /test/myfile.txt
.
Next, suppose you want to copy a file or folder into a container. For example, this could be a configuration file or some other input to a long running computation that you would like to place into a created container before it starts. This is useful because it does not require the configuration file or other input to exist in the container image.
If you have a file, config.yml
, in the current directory on your local host and wish to copy it to an existing directory at /etc/my-app.d
in a container, this command can be used:
$ docker cp config.yml myappcontainer:/etc/my-app.d
If you have several files in a local directory /config
which you need to copy to a directory /etc/my-app.d
in a container:
$ docker cp /config/. myappcontainer:/etc/my-app.d
The above command will copy the contents of the local /config
directory into the directory /etc/my-app.d
in the container.
Finally, if you want to copy a symbolic link into a container, you typically want to copy the linked target and not the link itself. To copy the target, use the -L
option, for example:
$ ln -s /tmp/somefile /tmp/somefile.ln $ docker cp -L /tmp/somefile.ln myappcontainer:/tmp/
This command copies content of the local /tmp/somefile
into the file /tmp/somefile.ln
in the container. Without -L
option, the /tmp/somefile.ln
preserves its symbolic link but not its content.
April 2014, Originally compiled by William Henry (whenry at redhat dot com) based on docker.com source material and internal work. June 2014, updated by Sven Dowideit SvenDowideit@home.org.au May 2015, updated by Josh Hawn josh.hawn@docker.com