docker container cp
Description | Copy files/folders between a container and the local filesystem |
---|---|
Usage | docker container cp [OPTIONS] CONTAINER:SRC_PATH DEST_PATH|-
docker cp [OPTIONS] SRC_PATH|- CONTAINER:DEST_PATH |
Aliases | docker cp |
Description
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. However, if you specify the -a
option, docker cp
sets the ownership
to the user and primary group at the source.
If you specify the -L
option, docker cp
follows any symbolic link
in the SRC_PATH
. docker cp
doesn't create parent directories for
DEST_PATH
if they don't 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 exist- the file is saved to a file created at
DEST_PATH
- the file is saved to a file created at
DEST_PATH
does not exist and ends with/
- Error condition: the destination directory must exist.
DEST_PATH
exists and is a file- the destination is overwritten with the source file's contents
DEST_PATH
exists and is a directory- the file is copied into this directory using the basename from
SRC_PATH
- the file is copied into this directory using the basename from
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 directory
DEST_PATH
exists and is a file- Error condition: cannot copy a directory to a file
DEST_PATH
exists and is a directorySRC_PATH
does not end with/.
(that is: slash followed by dot)- the source directory is copied into this directory
SRC_PATH
does end with/.
(that is: slash followed by dot)- the content of the source directory is copied into this directory
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`
Options
Option | Default | Description |
---|---|---|
-a, --archive | Archive mode (copy all uid/gid information) | |
-L, --follow-link | Always follow symbol link in SRC_PATH | |
-q, --quiet | Suppress progress output during copy. Progress output is automatically suppressed if no terminal is attached |
Examples
Copy a local file into container
$ docker cp ./some_file CONTAINER:/work
Copy files from container to local path
$ docker cp CONTAINER:/var/logs/ /tmp/app_logs
Copy a file from container to stdout. Note cp
command produces a tar stream
$ docker cp CONTAINER:/var/logs/app.log - | tar x -O | grep "ERROR"
Corner cases
It isn't 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
. Both of the following examples do the same thing
in different ways (consider SRC_PATH
and DEST_PATH
are directories):
$ docker exec CONTAINER tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | tar Cxf DEST_PATH -
$ tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | docker exec -i CONTAINER 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
.