How to copy files from host to Docker container?

Question

I am trying to build a backup and restore solution for the Docker containers that we work with.

I have Docker base image that I have created, ubuntu:base, and do not want have to rebuild it each time with a Docker file to add files to it.

I want to create a script that runs from the host machine and creates a new container using the ubuntu:base Docker image and then copies files into that container.

How can I copy files from the host to the container?

Cohin

If you don't want to rebuild, why not "docker commit" ? That saves your image. – Persaud

Just a remark on a notion nobody has addressed: in general, treat containers as "ephemeral". There ARE use cases to copy files into/from a running container (testing, prototyping). But if you find yourself in a position where you can't rebuild what you need using Dockerfiles and/or compose, then you may be in a bad place. You generally don't want to be backing up containers as if they were OS or even VM objects. Generally speaking :-) – Victoir

Possible duplicate of Copying files from Docker container to host – Satinet

@BerenddeBoer's link is now outdated, here's the new URL: docs.docker.com/engine/reference/commandline/commit – Sing

Adding to @ScottPrive point: containers are designed for high availability, so in their case "backup" is another replica running simultaneously on another host and/or in another data center (one should have more than one host and ideally also multiple DC's in a single k8s cluster). – Veld

Answer 1

The cp command can be used to copy files.

One specific file can be copied TO the container like:

docker cp foo.txt container_id:/foo.txt

One specific file can be copied FROM the container like:

docker cp container_id:/foo.txt foo.txt

For emphasis, container_id is a container ID, not an image ID. (Use docker ps to view listing which includes container_ids.)

Multiple files contained by the folder src can be copied into the target folder using:

docker cp src/. container_id:/target
docker cp container_id:/src/. target

Reference: Docker CLI docs for cp

In Docker versions prior to 1.8 it was only possible to copy files from a container to the host. Not from the host to a container.

Fyke

also note this can be on the host vm or main OS and works either host to container or vm to host (or main os) – Omniscient

Is there a way to do this from within a dockerfile? – Multinational

In a Dockerfile you can use the ADD keyword to add files during build time. – Fyke

@h3nrik COPY preferred over ADD when applicable. – Murmurous

Note: You might have to use absolute paths. – Selie

use docker cp to copy from container to host works well, but when use it to copy files from host to container, no effect... anybody know why ? docker version: Docker version 1.10.3, build cb079f6-unsupported – Scevor

Can i copy multiple files using docker cp from host to container? – Deina

@Scevor I thought I had the same issue, but it was just a wrong use of cp. See this to copy the content of a directory. It's also explained in the docs of course. – Hagberry

Worth noting (at least at Docker 18.09.1) that "filesystem operations against a running Hyper-V container are not supported". – Felting

docker cp foo.txt mycontainer:/ to keep filename the same ("foo.txt") inside container – Anecdotage

sudo docker cp 6eae0949649c:/app/output.txt output.txt shows open /home/rajan/Desktop/bashapp/output.txt: permission denied. Any solution? – Juju

@Scevor For me when I did docker cp foo.txt container_id:/foo.txt ,it got copied to root directory. When I opened shell it was open in another directory specified in dockerfile's working directory. So beware, it copied to absolute path and not relative to working directory specified in dockerfile – Koy

also, it's worth mentioning about changing the owner of the copied files. use chown before using the files. It's one of the prominent issues when you copy files from windows machines. – Rodmur

Heads up: if you see 'must specify at least one container source', you probably forgot the : in container_id: – Potman

How to copy Directory from host to container? – Larousse

If you are using an old Docker <1.8, then you can learn here: https://mcmap.net/q/40960/-docker-cp-path-not-specified how to copy files into container. – Nazarius

Answer 2

1. Get container name or short container id:

   $ docker ps
   

2. Get full container id:

   $ docker inspect -f   '{{.Id}}'  SHORT_CONTAINER_ID-or-CONTAINER_NAME
   

3. Copy file:

   $ sudo cp path-file-host /var/lib/docker/aufs/mnt/FULL_CONTAINER_ID/PATH-NEW-FILE
   

EXAMPLE:

$ docker ps

CONTAINER ID      IMAGE    COMMAND       CREATED      STATUS       PORTS        NAMES

d8e703d7e303   solidleon/ssh:latest      /usr/sbin/sshd -D                      cranky_pare

$ docker inspect -f   '{{.Id}}' cranky_pare

or

$ docker inspect -f   '{{.Id}}' d8e703d7e303

d8e703d7e3039a6df6d01bd7fb58d1882e592a85059eb16c4b83cf91847f88e5

$ sudo cp file.txt /var/lib/docker/aufs/mnt/**d8e703d7e3039a6df6d01bd7fb58d1882e592a85059eb16c4b83cf91847f88e5**/root/file.txt

Grum

For me the host's mounting path didn't contain aufs but a devicemapper. Easiest way to check the containers mounting path (while it is running) is to run the command mount. – Betrothed

I tried the above solution. It copied the files into the docker specific directory. However, when I use bash for docker container, the files dont show up there. Is there something I am missing ? – Lennox

The new path is /var/lib/docker/devicemapper/mnt/<<id>>/rootfs/ – Hokkaido

For me, on Docker 1.4.1 (current latest), it's /var/lib/docker/aufs/diff/<id>/ – Kathernkatheryn

Why not just use docker inspect -f '{{.Volumes}}' gitlab_app_7.10 to get the answer from docker itself? – Lowelllowenstein

@Lennox I had a similar problem with the file not showing up in the container when I used this method. This was because the target location was in a volume. So I had to use docker inspect to find the location of the volumes to copy the file directly into there instead. Then it showed up in the container. The volumes were under /var/lib/docker/vfs/dir/ – Willyt

You can use docker inspect -f '{{.Mounts}}' d8e703d7e303 – Mesdemoiselles

what about for poor MacOS users? The mount directory is in /var/lib for me. find / -name docker was not helpful either. – Leenaleeper

Answer 3

Typically there are three types:

1. From a container to the host

   docker cp container_id:./bar/foo.txt .
   

Also docker cp command works both ways too.

2. From the host to a container

   docker exec -i container_id sh -c 'cat > ./bar/foo.txt' < ./foo.txt
   

3. Second approach to copy from host to container:

   docker cp foo.txt mycontainer:/foo.txt
   

4. From a container to a container mixes 1 and 2

   docker cp container_id1:./bar/foo.txt .
   
   docker exec -i container_id2 sh -c 'cat > ./bar/foo.txt' < ./foo.txt
   

Maus

docker cp works both ways. No need to exec, cat, and redirect. docker cp host_file.txt container:/path/ – Whale

And if the requirements is to copy more than just one file, tar comes pretty handy, something like the following: tar -czvf tmp.tar.gz *.* && docker exec -i container_id2 sh -c 'cat > ./bar/tmp.tar.gz && tar -xzvf tmp.tar.gz' < ./tmp.tar.gz – Aestival

This is actually gold! – Lindesnes

When copying a whole directory: the command described by @Aestival may have a performance advantage, but for the sake of simplicity, you could also use the -r or -a flags : docker cp -a ... – Inconspicuous

Answer 4

The cleanest way is to mount a host directory on the container when starting the container:

{host} docker run -v /path/to/hostdir:/mnt --name my_container my_image
{host} docker exec -it my_container bash
{container} cp /mnt/sourcefile /path/to/destfile

Bear

how can you run container? i thought you can do that only with an image. – Rodolphe

I can't get it work when container is existing aka has run before. Tar below works nice. – Eb

The only way this worked for me was attaching the volume alongside running the image (instantiating the container). Ended up with: docker run -d -p -v /host/path:/mnt --name container_name image_name – Wilburnwilburt

This doesnt work for me. Atleast cannot run a container. Can run only image – Harts

I'm amazed that docker cp is a one-way operation! – Keos

Answer 5

The following is a fairly ugly way of doing it but it works.

docker run -i ubuntu /bin/bash -c 'cat > file' < file

Yulandayule

This works great! But don't forget to commit the change: docker commit `docker ps -l -q` ubuntu-with-file. Else the change will be lost (use whatever name you want instead of ubuntu-with-file) – Ginnygino

In adition, we can use new docker exec feature to work with running container: docker exec -it <container_id> bash -c 'cat > /path/to/container/file' < /path/to/host/file/ – Cough

@Cough I think it should be docker exec -i ... instead of -it, because there's no TTY when piping in from a file. – Sweetandsour

I've managed to implement this in Java with Remote API github.com/highel/docker-rest-file-upload/blob/master/… – Nominative

This really seems like simplest solution for a single file. – Gebhardt

If you are still stuck on an old version of Docker (as I am) and want to copy a whole directory, you could do this: tar -c -v -f - /path/to/host/directory | docker exec -i <container-name> bash -c 'tar -x -v --strip-components 1 -f - -C /path/to/container/directory' – Cas

Hmm, this did not work for me with Docker 19.03.8, host Centos 8, ubuntu:18.04 image. It did create file on the container, but it was blank. – Neona

Answer 6

If you need to do this on a running container you can use docker exec (added in 1.3).

First, find the container's name or ID:

$ docker ps
CONTAINER ID        IMAGE                        COMMAND             CREATED             STATUS              PORTS                   NAMES
b9b7400ddd8f        ubuntu:latest                "/bin/bash"         2 seconds ago       Up 2 seconds                                elated_hodgkin

In the example above we can either use b9b7400ddd8f or elated_hodgkin.

If you wanted to copy everything in /tmp/somefiles on the host to /var/www in the container:

$ cd /tmp/somefiles
$ tar -cv * | docker exec -i elated_hodgkin tar x -C /var/www

We can then exec /bin/bash in the container and verify it worked:

$ docker exec -it elated_hodgkin /bin/bash
root@b9b7400ddd8f:/# ls /var/www
file1  file2

Coverture

Works great on on docker 1.16 on Centos 7.4 Great innovative idea. – Sansculotte

Answer 7

1. Create a new dockerfile and use the existing image as your base.

   FROM myName/myImage:latest
   
   ADD myFile.py bin/myFile.py
   

2. Then build the container:

   docker build .
   

Euratom

It will create a new image, not directly a new container. If you reuse this image while myFile.py as changed, it will use the older version of the file, unless you rebuild the image. – Health

I find this the fastest way only if you're testing on a remote server. – Corell

According to this most people should use COPY rather than ADD. But for local files (as in this example) they're equivalent. – Conversant

Answer 8

The solution is given below,

From the Docker shell,

root@123abc:/root#  <-- get the container ID

From the host

cp thefile.txt /var/lib/docker/devicemapper/mnt/123abc<bunch-o-hex>/rootfs/root

The file shall be directly copied to the location where the container sits on the filesystem.

Thrall

Great answer. In newer docker releases the path has been renamed to /var/lib/docker/aufs/mnt/ – Palaeozoic

the devicemapper path doesn't seem to be work on fedora with docker 1.6. Have put it up as a separate Q, #29939919, any comments would be appreciated. – Eckman

The file /var/lib/docker does not exist.... – Gadgeteer

Renamed to /var/lib/docker/overlay2/e0cRANDOMe05/diff/home/ although it is better to stop container before any changes – Gotten

Answer 9

Another solution for copying files into a running container is using tar:

tar -c foo.sh | docker exec -i theDockerContainer /bin/tar -C /tmp -x

Copies the file foo.sh into /tmp of the container.

Edit: Remove reduntant -f, thanks to Maartens comment.

Bencion

This is good if you need to send a whole directory. For a single file, Erik's answer is simpler. – Gebhardt

@Kelvin: But tar also preserves file attributes and name. Amongst others that means you only have to type the name once (and there you get tab completion from your shell). So I'd say tar is actually simpler, as long as it is installed in the container. – Nievelt

The -f - is a bit redundant though, default behaviour is to write to stdout anyway. – Nievelt

this means there is a host dependency on tar – Medea

You are right - you need tar to be installed on the host and within the container. Nowadays using docker cp is the better solution. – Bencion

Answer 10

This is a direct answer to the question 'Copying files from host to Docker container' raised in this question in the title.

Try docker cp. It is the easiest way to do that and works even on my Mac. Usage:

docker cp /root/some-file.txt some-docker-container:/root

This will copy the file some-file.txt in the directory /root on your host machine into the Docker container named some-docker-container into the directory /root. It is very close to the secure copy syntax. And as shown in the previous post, you can use it vice versa. I.e., you also copy files from the container to the host.

And before you downlink this post, please enter docker cp --help. Reading the documentation can be very helpful, sometimes...

If you don't like that way and you want data volumes in your already created and running container, then recreation is your only option today. See also How can I add a volume to an existing Docker container?.

Isotope

Answer 11

To copy a file from host to running container

docker exec -i $CONTAINER /bin/bash -c "cat > $CONTAINER_PATH" < $HOST_PATH

---

Based on Erik's answer and Mikl's and z0r's comments.

Sullen

The accepted solutions sometimes disturbs the indentation of files when transferring to running containers. This works perfect for such cases – Keilakeily

Answer 12

I tried most of the (upvoted) solutions here but in docker 17.09 (in 2018) there is no longer /var/lib/docker/aufs folder.

This simple docker cp solved this task.

docker cp c:\path\to\local\file container_name:/path/to/target/dir/

How to get container_name?

 docker ps 

There is a NAMES section. Don't use aIMAGE.

Sesqui

Answer 13

With Docker 1.8, docker cp is able to copy files from host to container. See the Docker blog post Announcing Docker 1.8: Content Trust, Toolbox, and Updates to Registry and Orchestration.

Bencion

here is an example docker cp foo.txt mycontainer:/foo.txt – Entasis

Answer 14

To copy files/folders between a container and the local filesystem, type the command:

docker cp {SOURCE_FILE} {DESTINATION_CONTAINER_ID}:/{DESTINATION_PATH}

For example,

docker cp /home/foo container-id:/home/dir

To get the contianer id, type the given command:

docker ps

The above content is taken from docker.com.

Leenaleeper

Answer 15

Assuming the container is already running, type the given command:

# cat /path/to/host/file/ | docker exec -i -t <container_id> bash -c "/bin/cat > /path/to/container/file"

To share files using shared directory, run the container by typing the given command:

# docker run -v /path/to/host/dir:/path/to/container/dir ...

Note: Problems with permissions might arise as container's users are not the same as the host's users.

Methaemoglobin

In addition: docker exec -it <container_id> bash -c 'cat > /path/to/container/file' < /path/to/host/file/ – Cough

Note that cat will not be terminated once it exits. If it matters to you (if you are copying bash scripts, bash will refuse to run them), you should run lsof | grep yourfilename and kill the cat process that holds the said file. – Methaemoglobin

Thx! Great tip. Can you pls tell me how to kill this process with one command? Something like kill $(lsof | grep /path/to/file | sed ...). I'll be grateful for your help – Cough

kill $(docker top CONTAINERNAME | sed -n '/cat$/p' | sed 's/^root[^0-9]\+\([0-9]\+\).*$/\1/') – Cough

Answer 16

Container Up Syntax:

docker run -v /HOST/folder:/Container/floder 

In docker File

COPY hom* /myFolder/        # adds all files starting with "hom"
COPY hom?.txt /myFolder/    # ? is replaced with any single character, e.g., "home.txt"

Pricking

How would you copy more than 1, but specific files to the container? e.g. files: alpha.txt and bravo.txt – Delrio

Answer 17

docker cp [OPTIONS] SRC_PATH CONTAINER:DEST_PATH

The destination path must be pre-exist

Agripinaagrippa

Answer 18

This is the command to copy data from Docker to Host:

docker cp container_id:file path/filename /hostpath

docker cp a13fb9c9e674:/tmp/dgController.log /tmp/

Below is the command to copy data from host to docker:

docker cp a.txt ccfbeb35116b:/home/

Lo

Answer 19

In a docker environment, all containers are found in the directory:

/var/lib/docker/aufs/required-docker-id/

To copy the source directory/file to any part of the container, type the given command:

sudo cp -r mydir/ /var/lib/docker/aufs/mnt/required-docker-id/mnt/

Gurtner

Answer 20

Docker cp command is a handy utility that allows to copy files and folders between a container and the host system.

If you want to copy files from your host system to the container, you should use docker cp command like this:

docker cp host_source_path container:destination_path

List your running containers first using docker ps command:

abhishek@linuxhandbook:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              
  PORTS               NAMES
  8353c6f43fba        775349758637        "bash"              8 seconds ago       Up 7 
  seconds                            ubu_container

You need to know either the container ID or the container name. In my case, the docker container name is ubu_container. and the container ID is 8353c6f43fba.

If you want to verify that the files have been copied successfully, you can enter your container in the following manner and then use regular Linux commands:

docker exec -it ubu_container bash

Copy files from host system to docker container Copying with docker cp is similar to the copy command in Linux.

I am going to copy a file named a.py to the home/dir1 directory in the container.

docker cp a.py ubu_container:/home/dir1

If the file is successfully copied, you won’t see any output on the screen. If the destination path doesn’t exist, you would see an error:

abhishek@linuxhandbook:~$ sudo docker cp a.txt ubu_container:/home/dir2/subsub
        Error: No such container:path: ubu_container:/home/dir2

If the destination file already exists, it will be overwritten without any warning.

You may also use container ID instead of the container name:

docker cp a.py 8353c6f43fba:/home/dir1

Agra

Answer 21

Try docker cp.

Usage:

docker cp CONTAINER:PATH HOSTPATH

It copies files/folders from PATH to the HOSTPATH.

Gad

He asks from host to container, not the other way round. – Catafalque

Actually, it works with docker cp: https://mcmap.net/q/40963/-how-to-copy-files-from-local-machine-to-docker-container-on-windows – Commoner

From host to container: docker cp HOSTPATH CONTAINER:PATH works for me. – Heeltap

Answer 22

If the host is CentOS or Fedora, there is a proxy NOT in /var/lib/docker/aufs, but it is under /proc:

cp -r /home/user/mydata/* /proc/$(docker inspect --format "{{.State.Pid}}" <containerid>)/root

This cmd will copy all contents of data directory to / of container with id "containerid".

Windpipe

This is not unique to Redhat: it also works on Debian. (maybe all Gnu/Linux with /proc). Also extend path to put file somewhere else, not just root. – Efficiency

Answer 23

Many that find this question may actually have the problem of copying files into a Docker image while it is being created (I did).

In that case, you can use the COPY command in the Dockerfile that you use to create the image.

See the documentation.

Hughs

Answer 24

tar and docker cp are a good combo for copying everything in a directory.

Create a data volume container

docker create --name dvc --volume /path/on/container cirros

To preserve the directory hierarchy

tar -c -C /path/on/local/machine . | docker cp - dvc:/path/on/container

Check your work

docker run --rm --volumes-from dvc cirros ls -al /path/on/container

Cutcheon

Answer 25

In case it is not clear to someone like me what mycontainer in @h3nrik answer means, it is actually the container id. To copy a file WarpSquare.mp4 in /app/example_scenes/1440p60 from an exited docker container to current folder I used this.

docker cp `docker ps -q -l`:/app/example_scenes/1440p60/WarpSquare.mp4 .

where docker ps -q -l pulls up the container id of the last exited instance. In case it is not an exited container you can get it by docker container ls or docker ps

Exhilarative

You can list ids of exited containers with docker ps -a or docker container ls -a. – Fyke

Answer 26

docker cp SRC_PATH CONTAINER_ID:DEST_PATH

For example, I want to copy my file xxxx/download/jenkins to tomcat

I start to get the id of the container Tomcat

docker ps

CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                    NAMES
63686740b488        tomcat              "catalina.sh run"   12 seconds ago      Up 11 seconds       0.0.0.0:8080->8080/tcp   peaceful_babbage

docker cp xxxx/download/jenkins.war  63686740b488:usr/local/tomcat/webapps/

Melancon

Answer 27

docker cp [OPTIONS] SRC_PATH CONTAINER:DEST_PATH to copy from host machine to container.

docker cp [OPTIONS] CONTAINER:SRC_PATH DEST_PATH to copy from the container to the host machine.

Prolegomenon

Answer 28

This is a onliner for copying a single file while running a tomcat container.

docker run -v /PATH_TO_WAR/sample.war:/usr/local/tomcat/webapps/myapp.war -it -p 8080:8080 tomcat

This will copy the war file to webapps directory and get your app running in no time.

Necessarian

-v will mount (i.e. create a link), not copy – Prothallus

the difference in the result is that mounting hides the previous container content, e.g. if you mount a host folder on a container folder you cannot see anymore the previous container folder content – Edaedacious

Answer 29

This is what worked for me

#Run the docker image in detached mode 
$docker run -it -d test:latest bash

$ docker ps
CONTAINER ID        IMAGE               COMMAND
a6c1ff6348f4        test:latest     "bash"

#Copy file from host to container
sudo docker cp file.txt a6c1ff6348f4:/tmp

#Copy the file from container to host
docker cp test:/tmp/file.txt /home

Kairouan

Answer 30

The best way for copying files to the container I found is mounting a directory on host using -v option of docker run command.

Howie

Answer 31

There are good answers, but too specific. I find out docker ps is good way to get container id you're interested in. Then do

mount | grep <id>

to see where the volume is mounted. That's

/var/lib/docker/devicemapper/mnt/<id>/rootfs/

for me, but it might be a different path depending on the OS and configuration. Now simply copy files to that path.

Using -v is not always practical.

Frisette

Answer 32

My favorite method:

CONTAINERS:

CONTAINER_ID=$(docker ps | grep <string> | awk '{ print $1 }' | xargs docker inspect -f '{{.Id}}')

file.txt

mv -f file.txt /var/lib/docker/devicemapper/mnt/$CONTAINER_ID/rootfs/root/file.txt

or

mv -f file.txt /var/lib/docker/aufs/mnt/$CONTAINER_ID/rootfs/root/file.txt

Lipp

the devicemapper path doesn't seem to be work on fedora with docker 1.6. Have put it up as a separate Q, #29939919, any comments would be appreciated. – Eckman

Answer 33

I just started using docker to compile VLC, here's what you can do to copy files back and forth from containers:

su -
cd /var/lib/docker
ls -palR > /home/user/dockerfilelist.txt

Search for a familiar file in that txt and you'll have the folder, cd to it as root and voila! copy all you want.

There might be a path with "merged" in it, I guess you want the one with "diff" in it.

Also if you exit the container and want to be back where you left off:

docker ps -a
docker start -i containerid

I guess that's usefull when you didn't name anything with a command like

docker run -it registry.videolan.org:5000/vlc-debian-win64 /bin/bash

Sure the hacker method but so what!

Tohubohu

Answer 34

You can use below commands

1. Copy file from host machine to docker container

   docker cp /hostfile container_id:/to_the_place_you_want_the_file_to_be

2. Copy file from docker container to host machine

   docker cp container_id:src_path to_the_place_you_want_the_file_to_be

Alicaalicante

Answer 35

You can just trace the IP address of your local machine using

ifconfig

Then just enter into your Docker container and type

scp user_name@ip_address:/path_to_the_file destination

In any case if you don't have an SSH client and server installed, just install it using:

sudo apt-get install openssh-server

Cerecloth

This is a horrible solution in terms of security. – Planetstruck

Answer 36

In my opinion you have not to copy files inside image but you can use GIT or SVN for your files and then set a volume synchronized with a local folder. Use a script while runing container who can check if data already exist in local folder if not copy it from GIT repository. That make your image very lightweight.

Godiva

This seems like a security risk and access nightmare waiting to happen. How do you provide access to the git repository from within your image? Even assuming it's a public repository you're going to assume the host your container runs on has access to that repo. – Whale

I'm agree with you if git is used inside docker container. But in our case, the script is running from the host machine – Godiva

Answer 37

The simpliest way to achieve this is,

1. Find the container id
2. docker cp <filename> <container-id>:<path>

Hetaerism

What would a valid Windows path be in a Docker container? do I use C:\ or C:/ – Transformism

For windows I think it is C:\ but if this doesn't work then try C:\\ since single \ is used as espace character. – Hetaerism

Answer 38

If you're able to use a container registry, the appendlayer Python package does what you're asking for:

Assume that ubuntu:base is already available in the registry.

You can then add a new layer consisting of some local files on top of it using the script, saving the whole thing as a new image (i.e. ubuntu:test).

$ pip install appendlayer
$ tar cvf - test.txt | appendlayer <host> <repository> <old-tag> <new-tag>

All without having to rebuild or even download any of the image data to your local machine.

Casto

Answer 39

I wanted to have a build process happen in the container without files like the .git folder, but I want those files when I run the container interactively to debug problems. Like Ben Davis's answer, this executes the file copy within the container. But I don't want to have to actually run that command myself when I enter the container. Thus the following script will do the trick:

# mount the current [project] directory as read only
docker run --name my_container -v $(pwd):/mnt/application:ro -itd my_image /bin/bash
# copy the missing project files from the mounted directory
docker exec -it my_container /bin/bash -c 'cp -rnT /mnt/application $HOME/application'
# interactively use the container
docker attach my_container

This leaves behind a my_container container instance. To run the command again, you would have to write docker rm my_container. Or instead, if you wanted to get into that container instance again, you could execute docker start my_container && docker attach my_container.

Note the cp -n flag, which prevents overwriting files if they already exist in the destination. The :ro portion does not allow the host files to be changed. And you could change $(pwd) to a specific directory, like /home/user/dev/application.

Zobias

Answer 40

As of now (2024), Docker Desktop provides a clear UI application to make things like file changes much easier and intuitive.

Simply open the Container details page, go to the 'Files' tab and 'right-click' on a particular folder/file to save or import.

Hope it helps

Hundredpercenter

Answer 41

Where you don't have a directory defined as a volume in the Dockerfile, the /var/lib/docker/aufs/mnt// will work. But there are cases where the directory within the container is defined as a volume. In this case, the contents under aufs/mnt/*/ and the contents seen by the container are different.

You will need to inspect the container using docker inspect and then, look for volumes. There you will find a mention for something like /var/lib/docker/vfs/dir/fe940b... (the id). You will need to add/modify the files here instead of under aufs/mnt/*.

The confusing part is that the files also appear under /aufs/mnt/*. I spent quite a while scratching my head why changes here didn't work for me. Hope this helps someone.

Belen

Answer 42

I'd mount and then run the image with a daemon, just any as given here;

docker run -d -v /blah1/blah2:/mnt --name mntcontainer ubuntu /bin/sh -c "while true; do echo hello world; sleep 1; done"

then

docker exec -it mntcontainer bash

Cranmer

Answer 43

Another workaround is using the good old scp. This is useful in the case you need to copy a directory.

From your host run:

scp FILE_PATH_ON_YOUR_HOST IP_CONTAINER:DESTINATION_PATH
scp foo.txt 172.17.0.2:foo.txt

In the case you need to copy a directory:

scp -r DIR_PATH_ON_YOUR_HOST IP_CONTAINER:DESTINATION_PATH
scp -r directory 172.17.0.2:directory

be sure to install ssh into your container too.

apt-get install openssh-server

Harrier

I had no issue using docker cp to copy folders as well. As a side note for others, I normally don't like to read the docs because they are often times hard to understand but the docs on the docker cp command are simple. – Sower

Answer 44

If using Windows as host, you can use WinSCP to connect to Docker and transfer files through the GUI.

If on Linux, the scp command would also work through the terminal.

Maclaine

Answer 45

One thing which I tried and it worked

Once you spin up your docker container and if you create any file under that container; You can easily access that file from below location of your docker host:-

cd /var/lib/docker/aufs/containers/container_id/tmp

Try once!

Willemstad

Answer 46

real deal is:

docker volume create xdata
docker volume inspect xdata

so you see its mount poit dir.
just copy your stuff there
then

docker run  --name=example1 --mount source=xdata,destination=/xdata -it yessa bash

where yessa is image name

Maggi

Answer 47

Using the following command from outside the container, I was able to copy file from my host machine to the container.

 487b00c94dd4 = Container ID
D:\demo\demo.tar= Source Url
/myfolder= Container Url

 
docker cp "D:\demo\demo.tar" 487b00c94dd4:/myfolder

Blancablanch

Answer 48

I simply copy the file directly from where the container is located from the host machine.

For example:

First find out the container id:

root@**3aed62678d54**:/home#

And then from the host, let's say the file is in the home directory:

root@saasdock:/home/dnepangue# cp cheering_nasa.gif /var/lib/docker/aufs/mnt/**3aed62678d54**a5df47a4a00a58bb0312009c2902f8a37498a1427052e8ac454b/home/

Back to the container...

root@**3aed62678d54**:/home# ls cheering_nasa.gif

Dolerite

Answer 49

I usually create python server using this command

python -m SimpleHTTPServer

in the particular directory and then just use wget to transfer file in the desired location in docker. I know it is not the best way to do it but I find it much easier.

Vulnerary

docker cp --help – Whale

Answer 50

Copy from container to host dir

docker cp [container-name/id]:./app/[index.js] index.js

(assume you have created a workdir /app in your dockerfile)

Copy from host to container

docker cp index.js [container-name/id]:./app/index.js

Inexecution

Answer 51

Bring dotfile into shell session (using base64 escape)

There are times when executing a separate interactive command to the shell launch is cumbersome. Here's what I do when I want to copy a dotfile into my container so my shell will contain my customizations

docker exec -u root -it mycontainername bash -c "echo "$(cat ~/.bashrc | base64 -w 0)" | base64 --decode > /tmp/.bashrc_inside_container; bash --rcfile /tmp/.bashrc_inside_container"

Ader

Answer 52

I would highly recommend that you do not copy any files to any container, instead use a docker volume. This will allow you to persist files on your host. If you do not do it this way, then when its time to upgrade your docker image/container (you should do this on any release that contains any CVE's) then you would be removing the files you just uploaded.

I SFTP to my Docker Host (Linux Server usually), uploading the file there.

Kerbela