I'm trying to change the default data folder of docker images, containers, etc to a different path. Snap installation of docker has such folder at /var/snap/docker/common/var-lib-docker.
Theoretically I could change that with data-root option in deamon.json. But, if I change the daemon.json adding "data-root": "/home/user/docker" docker won't start due to a conflict with flags (which always has the previously described default path on it).
I do can start docker with my custom path if I stop it and then start it like this: sudo snap start docker.dockerd --data-root=/home/user/docker. Which is not pretty but works. Is there a way to change docker snap flags on startup or make it prefers the daemon.json options?
I've read this archived post, which treats such issue on docker version 17, but it didn't helped much the same way several other material I found online. I seems that symbolic link may be a way tho...
I'm using docker 19.03.11, snap installed on Ubuntu 20.04.
P.s.: The new path is on a second HDD mounted as my home directory. Changing the path will save space in my system SSD.
Thanks for the attention.
From https://github.com/docker-snap/docker-snap/issues/3 and https://askubuntu.com/questions/550348/how-to-make-mount-bind-permanent, the not-perfect-but-working solution seems to be the bind mount between /var/snap/docker/common/var-lib-docker and /home/username/docker which is the previous docker data-root I had before installing docker with snap.
So first, clear the data-root option in daemon.json.
Then add the following at the end of /etc/fstab with the following command:
echo '/home/username/docker /var/snap/docker/common/var-lib-docker none bind' >> /etc/fstab
After reboot, your docker data root will be stored in /home/username/docker
I ran out of space on an Ubuntu VirtualBox VM and had to do the following:
Stop the VM and create a new Fixed Volume
Start the VM and make sure the new volume was mounted
Stop the docker service
sudo systemctl stop docker.service
sudo systemctl stop docker.socket
Copy /var/lib/docker to new volume
sudo rsync -aqxP /var/lib/docker/ /media/username/spare\ disk/
Update /etc/docker/daemon.json
{
"data-root": "/media/username/spare disk/docker",
"storage-driver": "overlay2"
}
Reload systemd and start docker service
sudo systemctl daemon-reload
sudo systemctl start docker
See: https://docs.docker.com/config/daemon/systemd/#runtime-directory-and-storage-driver
When I launch a container from rhel7.3 image, the default container size is 10GB. I want to increase it to 20GB. I tried the below ways but I had no luck
1) Added "DOCKER_STORAGE_OPTIONS": "--storage-opt dm.basesize=20G" in /etc/docker/daemon.json file. /etc/docker/daemon.json file is not there by default so I had to add it and tried restarting docker. Restart fails with the below error:
"unable to configure the Docker daemon with file /etc/docker/daemon.json: the following directives don't match any configuration option: DOCKER_STORAGE_OPTIONS\n"
2) Added "dm.basesize=20G" parameter while I launch the conatiner
docker run --privileged --storage-opt "dm.basesize=20G" -d IMAGE_ID
but it fails to launch with error
"docker: Error response from daemon: Unknown option dm.basesize."
Any help on how I can achieve to launch a container with 20GB instead of the default 10GB?
Thanks,
Premchand
I changed the storage type to "Overlay" by the following steps
1) Added {"storage-driver": "overlay"} in /etc/docker/daemon.json file. This file was not there in rhel 7.3 so I added it manually.
2) Restarted docker
My issue of increasing the container volume is resolved as each container get total amount of volume available on the host.
Had the same issue as you, after a lot of research i found a simple solution:
stop the docker service:
sudo systemctl stop docker
edit your docker service file, located at:
/usr/lib/systemd/system/docker.service
find the execution line:
ExecStart=/usr/bin/dockerd
and change it to: ExecStart=/usr/bin/dockerd --storage-opt dm.basesize=20G
start docker service again:
sudo systemctl start docker
all done.
You have the correct flag, --storage-opt dm.basesize=some_size, however this is an argument that should be given to dockerd, not docker.
Try reformatting your daemon.json file to contain:
"storage-opt": [ "dm.basesize=20G" ]
I am able to run a tensorflow container w/ access to the GPU from the command line w/ the following command
$ sudo docker run --runtime=nvidia --rm gcr.io/tensorflow/tensorflow:latest-gpu
I would like to be able to run this container from docker-compose. Is it possible to specify the --runtime flag from docker-compose.yml?
Currently (Aug 2018), NVIDIA container runtime for Docker (nvidia-docker2) supports Docker Compose.
Yes, use Compose format 2.3 and add runtime: nvidia to your GPU service. Docker Compose must be version 1.19.0 or higher.
Example docker-compose.yml:
version: '2.3'
services:
nvsmi:
image: ubuntu:16.04
runtime: nvidia
environment:
- NVIDIA_VISIBLE_DEVICES=all
command: nvidia-smi
More example from NVIDIA blog uses Docker Compose to show how to launch multiple GPU containers with the NVIDIA Container Runtime.
You should edit /etc/docker/daemon.json, adding the first level key "default-runtime": "nvidia", restart docker daemon (ex. "sudo service docker restart") and then all containers on that host will run with nvidia runtime.
More info on daemon.json here
Or better: using systemd and assuming the path is /usr/libexec/oci/hooks.d/nvidia
Configure
mkdir -p /etc/systemd/system/docker.service.d/
cat > /etc/systemd/system/docker.service.d/nvidia-containers.conf <<EOF
[Service]
ExecStart=
ExecStart=/usr/bin/dockerd -D --add-runtime nvidia=/usr/libexec/oci/hooks.d/nvidia --default-runtime=nvidia
EOF
Restart
systemctl daemon-reload
systemctl restart docker
Demo
Don't need to specify --runtime=nvidia since we set default-runtime=nvidia in the configuration step.
docker run --rm gcr.io/tensorflow/tensorflow:latest-gpu
Solution Inspired from my tutorial about KATA runtime.
Every Docker container will be configured with 10 GB disk space, which is the default configuration of devicemapper in CentOS. So how can I configure every container newly created with more than 10 GB disk space in default? (The host server is installed with CentOS 6 and Docker 1.7.1)
Yes you can. Use the dm.basesize attribute when starting the Docker daemon. For example:
docker daemon --storage-opt dm.basesize=50G ...
More info can be found in the official docs.
(optional) If you have already downloaded any image via docker pull you need to clean them first - otherwise they won't be resized
docker rmi your_image_name
Edit the storage config
vi /etc/sysconfig/docker-storage
There should be something like DOCKER_STORAGE_OPTIONS="...", change it to DOCKER_STORAGE_OPTIONS="... --storage-opt dm.basesize=100G"
Restart the docker deamon
service docker restart
Pull the image
docker pull your_image_name
(optional) verification
docker run -i -t your_image_name /bin/bash
df -h
I was struggling with this a lot until I found out this link http://www.projectatomic.io/blog/2016/03/daemon_option_basedevicesize/
turns out you have to remove/pull image after enlarging the basesize.
For those who use Mac, here's an easier solution:
Click "Preference" from Docker icon in the status bar:
Then navigate to "Disk" tab, adjust the disk image size with the slider. Docker will take a moment to restart.
That's it.
Above answers properly suggest we have to edit dm.basesize attribute of devicemapper,
but proposed solutions are out of date or simply does not work in my case.
First make sure your storage dirver is a devicemapper with:
docker info | grep "Storage Driver"
you can also check current max-size of container with: (default 10 gb)
docker info | grep "Base Device Size"
From devicemapper documentation
1) edit dm.basesize in etc/docker/daemon.json file, or create new one if does not exist
{
"storage-opts": [
"dm.basesize=30G"
]
}
2) restart docker deamon
sudo systemctl stop docker
sudo systemctl start docker
3) run again command below to check if size changed
docker info | grep "Base Device Size"
4) Its important to update current images so change is applied
From what I can tell, docker images are installed to /var/lib/docker as they are pulled. Is there a way to change this location, such as to a mounted volume like /mnt?
With recent versions of Docker, you would set the value of the data-root parameter to your custom path, in /etc/docker/daemon.json
(according to https://docs.docker.com/engine/reference/commandline/dockerd/#daemon-configuration-file).
With older versions, you can change Docker's storage base directory (where container and images go) using the -goption when starting the Docker daemon. (check docker --help).
You can have this setting applied automatically when Docker starts by adding it to /etc/default/docker
Following advice from comments I utilize Docker systemd documentation to improve this answer.
Below procedure doesn't require reboot and is much cleaner.
First create directory and file for custom configuration:
sudo mkdir -p /etc/systemd/system/docker.service.d
sudo $EDITOR /etc/systemd/system/docker.service.d/docker-storage.conf
For docker version before 17.06-ce paste:
[Service]
ExecStart=
ExecStart=/usr/bin/docker daemon -H fd:// --graph="/mnt"
For docker after 17.06-ce paste:
[Service]
ExecStart=
ExecStart=/usr/bin/dockerd -H fd:// --data-root="/mnt"
Alternative method through daemon.json
I recently tried above procedure with 17.09-ce on Fedora 25 and it seem to not work. Instead of that simple modification in /etc/docker/daemon.json do the trick:
{
"graph": "/mnt",
"storage-driver": "overlay"
}
Despite the method you have to reload configuration and restart Docker:
sudo systemctl daemon-reload
sudo systemctl restart docker
To confirm that Docker was reconfigured:
docker info|grep "loop file"
In recent version (17.03) different command is required:
docker info|grep "Docker Root Dir"
Output should look like this:
Data loop file: /mnt/devicemapper/devicemapper/data
Metadata loop file: /mnt/devicemapper/devicemapper/metadata
Or:
Docker Root Dir: /mnt
Then you can safely remove old Docker storage:
rm -rf /var/lib/docker
For new docker versions we need to use data-root as graph is deprecated in v17.05.0: official deprecated docs
Edit /etc/docker/daemon.json (if it doesn’t exist, create it) and include:
{
"data-root": "/new/path/to/docker-data"
}
Then restart Docker with:
sudo systemctl daemon-reload
sudo systemctl restart docker
A more detailed step-by-step explanation (including moving data) using Docker Storage with data-root can be found in: Blog post
In case of Windows a similar post Windows specific
Much easier way to do so:
Stop docker service
sudo systemctl stop docker
Move existing docker directory to new location
sudo mv /var/lib/docker/ /path/to/new/docker/
Create symbolic link
sudo ln -s /path/to/new/docker/ /var/lib/docker
Start docker service
sudo systemctl start docker
Since I haven't found the correct instructions for doing this in Fedora (EDIT: people pointed in comments that this should also work on CentOS and Suse) (/etc/default/docker isn't used there), I'm adding my answer here:
You have to edit /etc/sysconfig/docker, and add the -g option in the OPTIONS variable. If there's more than one option, make sure you enclose them in "". In my case, that file contained:
OPTIONS=--selinux-enabled
so it would become
OPTIONS="--selinux-enabled -g /mnt"
After a restart (systemctl restart docker) , Docker should use the new directory
Don't use a symbolic Link to move the docker folder to /mnt (for example).
This may cause in trouble with the docker rm command.
Better use the -g Option for docker.
On Ubuntu you can set it permanently in /etc/default/docker.io. Enhance or replace the DOCKER_OPTS Line.
Here an example:
`DOCKER_OPTS="-g /mnt/somewhere/else/docker/"
This solution works on Red Hat 7.2 & Docker 1.12.0
Edit the file
/lib/systemd/system/docker.service in your text editor.
add -g /path/to/docker/ at the end of ExecStart directive. The complete line should look like this.
ExecStart=/usr/bin/dockerd -g /path/to/docker/
Execute the below command
systemctl daemon-reload
systemctl restart docker
Execute the command to check docker directory
docker info | grep "loop file\|Dir"
If you have /etc/sysconfig/docker file in Red Hat or docker 1.7.1 check this answer.
In CentOS 6.5
service docker stop
mkdir /data/docker (new directory)
vi /etc/sysconfig/docker
add following line
other_args=" -g /data/docker -p /var/run/docker.pid"
then save the file and start docker again
service docker start
and will make repository file in /data/docker
Copy-and-paste version of the winner answer :)
Create this file with only this content:
$ sudo vi /etc/docker/daemon.json
{
"graph": "/my-docker-images"
}
Tested on Ubuntu 16.04.2 LTS in docker 1.12.6
The official way of doing this based on this Post-installation steps for Linux guide and what I found while web-crawling is as follows:
Override the docker service conf:
sudo systemctl edit docker.service
Add or modify the following lines, substituting your own values.
[Service]
ExecStart=
ExecStart=/usr/bin/dockerd --graph="/mnt/docker"
Save the file. (It creates: /etc/systemd/system/docker.service.d/override.conf)
Reload the systemctl configuration.
sudo systemctl daemon-reload
Restart Docker.
sudo systemctl restart docker.service
After this if you can nuke /var/lib/docker folder if you do not have any images there you care to backup.
For Debian/Ubuntu or Fedora, you can probably use the other answers. But if you don't have files under /etc/default/docker or /etc/sysconfig/docker, and your system is running systemd, you may want to follow this answer by h3nrik. I am using Arch, and this works for me.
Basically, you need to configure systemd to read the new docker image location as an environment variable, and pass that environment variable into the Docker daemon execution script.
For completeness, here is h3nrick's answer:
Do you have a /lib/systemd/system/docker.service file?
If so, edit it so that the Docker service uses the usual /etc/default/docker as an environment file: EnvironmentFile=-/etc/default/docker.
In the /etc/default/docker file then add DOCKER_OPTS="-g /home/rseixas/Programs/Docker/images".
At the end just do a systemctl daemon-reload && systemctl restart docker.
For further information please also have a look at the documentation.
As recommneded by #mbarthelemy this can be done via the -g option when starting the docker daemon directly.
However, if docker is being started as a system service, it is not recommended to modify the /etc/default/docker file. There is a guideline to this located here.
The correct approach is to create an /etc/docker/daemon.json file on Linux (or Mac) systems or %programdata%\docker\config\daemon.json on Windows. If this file is not being used for anything else, the following fields should suffice:
{
"graph": "/docker/daemon_files"
}
This is assuming the new location where you want to have docker persist its data is /docker/daemon_files
A much simpler solution is to create a soft link point to whatever you want, such as
link -s /var/lib/docker /mnt/whatever
It works for me on my CentOS 6.5 server.
I was having docker version 19.03.14. Below link helped me.
Check this Link
in /etc/docker/daemon.json file I added below section:-
{
"data-root": "/hdd2/docker",
"storage-driver": "overlay2"
}
On openSUSE Leap 42.1
$cat /etc/sysconfig/docker
## Path : System/Management
## Description : Extra cli switches for docker daemon
## Type : string
## Default : ""
## ServiceRestart : docker
#
DOCKER_OPTS="-g /media/data/installed/docker"
Note that DOCKER_OPTS was initially empty and all I did was add in the argument to make docker use my new directory
On Fedora 26 and probably many other versions, you may encounter an error after moving your base folder location as described above. This is particularly true if you are moving it to somewhere under /home. This is because SeLinux kicks in and prevents the docker container from running many of its programs from under this location.
The short solution is to remove the --enable-selinux option when you add the -g parameter.
On an AWS Ubuntu 16.04 Server I put the Docker images on a separate EBS, mounted on /home/ubuntu/kaggle/, under the docker dir
This snippet of my initialization script worked correctly
# where are the images initially stored?
sudo docker info | grep "Root Dir"
# ... not where I want them
# modify the configuration files to change to image location
# NOTE this generates an error
# WARNING: Usage of loopback devices is strongly discouraged for production use.
# Use `--storage-opt dm.thinpooldev` to specify a custom block storage device.
# see https://stackoverflow.com/questions/31620825/
# warning-of-usage-of-loopback-devices-is-strongly-discouraged-for-production-use
sudo sed -i ' s##DOCKER_OPTS=.*#DOCKER_OPTS="-g /home/ubuntu/kaggle/docker"# ' /etc/default/docker
sudo chmod -R ugo+rw /lib/systemd/system/docker.service
sudo cp /lib/systemd/system/docker.service /etc/systemd/system/
sudo chmod -R ugo+rw /etc/systemd/system/
sudo sed -i ' s#ExecStart.*#ExecStart=/usr/bin/dockerd $DOCKER_OPTS -H fd://# ' /etc/systemd/system/docker.service
sudo sed -i '/ExecStart/a EnvironmentFile=-/etc/default/docker' /etc/systemd/system/docker.service
sudo systemctl daemon-reload
sudo systemctl restart docker
sudo docker info | grep "Root Dir"
# now they're where I want them
For Mac users in the 17.06.0-ce-mac19 version you can simply move the Disk Image location from the user interface in the preferences option Just change the location of the disk image and it will work (by clicking Move disk Image) and restarting the docker. Using this approach I was able to use my external hardisk for storing docker images.
For Those looking in 2020. The following is for Windows 10 Machine:
In the global Actions pane of Hyper-V Manager click Hyper-V
Settings…
Under Virtual Hard Disks change the location from the
default to your desired location.
Under Virtual Machines change the
location from the default to your desired location, and click apply.
Click OK to close the Hyper-V Settings page.
This blog post helps me
Here are the steps to change the directory even after you’ve created Docker containers etc.
Note, you don’t need to edit docker.service or init.d files, as it will read the change from the .json file mentioned below.
Edit /etc/docker/daemon.json (if it doesn't exist, create it)
Add the following
{
"data-root": "/new/path/to/docker-data"
}
Stop docker
sudo systemctl stop docker
Check docker has been stopped
ps aux | grep -i docker | grep -v grep
Copy the files to the new location
sudo rsync -axPS /var/lib/docker/ /new/path/to/docker-data
Start Docker back up
sudo systemctl start docker
Check Docker has started up using the new location
docker info | grep 'Docker Root Dir'
Check everything has started up that should be running
docker ps
Leave both copies on the server for a few days to make sure no issues arise, then feel free to delete it.
sudo rm -r /var/lib/docker