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
Related
I want to store docker data on an external disk following the documentation on daemon.json configuration.
Error:
unable to configure the Docker daemon with file /etc/docker/daemon.json: the following directives don't match any configuration option: data-root
Using the documentation from docker, the "data-root" configuration option is used to move the data directory.
Using the documentation from docker, the new disk satisfies the prerequisites of xfs format,ftype=1 as per the output from xfs_info /path/to/disk |grep ftype
Using Centos7.9;
Stop docker
systemctl stop docker
Edit /etc/docker/daemon.json to include:
{
"data-root": "/var/lib/test"
}
Note; I found a source suggesting to add "storage-driver": "overlay2" to daemon.json - this has the same error at the top of this post
Sync the old and new directory
sudo rsync -axPSv /var/lib/docker/ /var/lib/test/
Start docker
systemctl start docker
Observe the error
systemctl status docker.service -l
localhost.localdomain dockerd-current[3615]: unable to configure the Docker daemon with file /etc/docker/daemon.json: the following directives don't match any configuration option: data-root
I also tried using the --bind as suggested here, and also this info for centos and SELinux all resulting in the error posted here.
I am using Docker 18.09 and I am trying to build some images for my work. The problem is that the images are always inside the root directory, precisely the /var/lib/docker/overlay2 are in /var/docker/. As there isn't enough space in my root directory, so I want to change this default directory to my other disk but none of the solutions I have looked upon the internet have worked for me.
I have gone through these already but none of them are working:
https://forums.docker.com/t/how-do-i-change-the-docker-image-installation-directory/1169
https://medium.com/#ibrahimgunduz34/how-to-change-docker-data-folder-configuration-33d372669056
How to change the docker image installation directory?
The default directory to store docker related data (containers, images and so on) is /var/lib/docker.
To override this default location use -g option.
While starting docker deamon use -g option.
dockerd -g /mnt/path/to/docker/dir
In your case, the best option is to attach some external storage to machine at some mountpoint. And mention that mountpoint in -g option.
Hope this helps.
Update:
-g option is deprecated. Use --data-root option. Check this.
I also faced similar issue with containerd used with rke2, I am using RKE2 with containerd and its storing all the images on /var/lib/rancher/rke2, which was causing VMs'/' partition getting full all the time.
I wanted to move containerd root directory to custom directory
I changed rke agent start command in rke service file and it worked.
Created a new FS /containerdata/containerd and configured rke service to point to this directory for containerd data
change /usr/local/lib/systemd/system/rke2-agent.service
ExecStart=/usr/local/bin/rke2 agent --data-dir /containerdata/containerd/
Reload and retart rke2-agent.service
systemctl daemon-reload
systemctl restart rke2-agent.service
This may cause pods to be unstable, but system gets stable over time.
I used the following technique when i too ran into this problem and using a different filesystem which had a larger size was the only available option left.
Stop the docker service.
sudo systemctl stop docker.service
Edit the docker.service file to include the new directory in the ExecStart line as below.
ExecStart=/usr/bin/dockerd -g /u01/docker -H fd:// --containerd=/run/containerd/containerd.sock
Reload daemon
sudo systemctl daemon reload
Restart docker
sudo systemctl start docker.service
Note: the docker.service file path is shown when you ran the systemctl stop docker.service
A much simpler and straightforward way out for this problem is to simply create a symbolic link to the new path once you move the existing folder like below.
sudo systemctl stop docker.service
sudo mv /var/lib/docker/ /
sudo ln -s / /var/lib/docker
sudo systemctl start docker.service
Purpose - What do I want to achieve?
I want to access systemctl from inside a container running a kubernetes node (ami: running debian stretch)
Working setup:
Node AMI: kope.io/k8s-1.10-debian-jessie-amd64-hvm-ebs-2018-08-17
Node Directories Mounted in the container to make systemctl work:
/var/run/dbus
/run/systemd
/bin/systemctl
/etc/systemd/system
Not Working setup:
Node AMI: kope.io/k8s-1.11-debian-stretch-amd64-hvm-ebs-2018-08-17
Node Directories Mounted in the container to make systemctl work:
/var/run/dbus
/run/systemd
/bin/systemctl
/etc/systemd/system
Debugging in an attempt to solve the problem
To debug this issue with the debian-stretch image not supporting systemctl with the same mounts as debian-jessie
1) I began by spinning up a nginx deployment by mounting the above mentioned volumes in it
kubectl apply -f https://k8s.io/examples/application/deployment.yaml
kubectl exec -it nginx-deployment /bin/bash
root#nginx-deployment-788f65877d-pzzrn:/# systemctl
systemctl: error while loading shared libraries: libsystemd-shared-
232.so: cannot open shared object file: No such file or directory
2) As the above issue showed the file libsystemd-shared-232.so not found. I found the actual path by looking into the node.
admin#ip-10-0-20-11:~$ sudo find / -iname 'libsystemd-shared-232.so'
/lib/systemd/libsystemd-shared-232.so
3) Mounted the /lib/systemd in the nginx pod and ran the systemctl again
kubectl exec -it nginx-deployment /bin/bash
root#nginx-deployment-587d866f54-ghfll:/# systemctl
systemctl: error while loading shared libraries: libcap.so.2:cannot
open shared object file: No such file or directory
4) Now the systemctl was failing with a new so missing error
root#nginx-deployment-587d866f54-ghfll:/# systemctl
systemctl: error while loading shared libraries: libcap.so.2: cannot
open shared object file: No such file or directory
5) To solve the above error i again searched the node for libcap.so.2 Found it in the below path.
admin#ip-10-0-20-11:~$ sudo find / -iname 'libcap.so.2'
/lib/x86_64-linux-gnu/libcap.so.2
6) Seeing the above directory not mounted in my pod. I mounted the below path in the nginx pod.
/lib/x86_64-linux-gnu mounted in the nginx pod(deployment)
7) The nginx pod is not able to come up after adding the above mount. Getting the below error:
$ k logs nginx-deployment-f9c5ff956-b9wn5
standard_init_linux.go:178: exec user process caused "no such file
or directory"
Please suggest how to debug further. And what all mounts are required to make systemctl work from inside a container in a debian stretch environment.
Any pointers to take the debugging further could be helpful.
Rather than mounting some of the library files from the host you can just install systemd in the container.
$ apt-get -y install systemd
Now, that won't necessarily make systemctl run. You will need systemd to be running in your container which is spawned by /sbin/init on your system. /sbin/init needs to run as root so essentially you would have to run this with the privileged flag in the pod or container security context on Kubernetes. Now, this is insecure and there is a long history about running systemd in a container where the Docker folks were mostly against it (security) and the Red Hat folks said that it was needed.
Nevertheless, the Red Hat folks figured out a way to make it work without the unprivileged flag. You need:
/run mounted as a tmpfs in the container.
/sys/fs/cgroup mounted as read-only is ok.
/sys/fs/cgroup/systemd/ mounted as read/write.
Use for STOPSIGNAL SIGRTMIN+3
In Kubernetes you need an emptyDir to mount a tmpfs. The others can be mounted as host volumes.
After mounting your host's /lib directory into the container, your Pod most probably will not start because the Docker image's /lib directory contained some library needed by the Nginx server that should start in that container. By mounting /lib from the host, the libraries required by Nginx will not be accessible any more. This will result in a No such file or directory error when trying to start Nginx.
To make systemctl available from within the container, I would suggest simply installing it within the container, instead of trying to mount the required binaries and libraries into the container. This can be done in your container's Dockerfile:
FROM whatever
RUN apt-get update && apt-get install systemd
No need to mount /bin/systemd or /lib/ with this solution.
I had a similar problem where one of the lines in my Dockerfile was:
RUN apt-get install -y --reinstall systemd
but after docker restart, when I tried to use systemctl command. The output was:
Failed to connect to bus: No such file or directory.
I solved this issue by adding following to my docker-compose.yml:
volumes:
- "/sys/fs/cgroup:/sys/fs/cgroup:ro"
It can be done also by:
sudo docker run -d -v /sys/fs/cgroup:/sys/fs/cgroup:ro {other options}
I get this error when I try to build a docker file
error creating aufs mount to /var/lib/docker/aufs/mnt
/6c1b42ce1a98b1c0f2d2a7f17c196221445f1054566065d4c607e4f1b99930eb-init:
invalid argument
What does it mean? How do I fix it?
I had some unresolved errors after removing /var/lib/docker/aufs, which a couple extra steps cleared up.
To add to #benwalther answer, since I lack the reputation to comment:
# Cleaning up through docker avoids these errors
# ERROR: Service 'master' failed to build:
# open /var/lib/docker/aufs/layers/<container_id>: no such file or directory
# ERROR: Service 'master' failed to build: failed to register layer:
# open /var/lib/docker/aufs/layers/<container_id>: no such file or directory
docker rm -f $(docker ps -a -q)
docker rmi -f $(docker images -a -q)
# As per #BenWalther's answer above
sudo service docker stop
sudo rm -rf /var/lib/docker/aufs
# Removing the linkgraph.db fixed this error:
# Conflict. The name "/jenkins_data_1" is already in use by container <container_id>.
# You have to remove (or rename) that container to be able to reuse that name.
sudo rm -f /var/lib/docker/linkgraph.db
sudo service docker start
If you try to use docker inside a persistent enable Live CD, you may encounter this error. I guess, it is due to the fact that you can't mount aufs inside overlayfs mounts, which is the persistent layer.
The solution was simply using different driver. I've used vfs in /etc/docker/daemon.json
Here it is
{
"storage-driver": "vfs"
}
I have removed /var/lib/docker/aufs/diff and got the same problem:
error creating aufs mount to /var/lib/docker/aufs/mnt/blah-blah-init: invalid argument
It solved by running the following commands:
docker stop $(docker ps -a -q);
docker rm $(docker ps -a -q);
docker rmi -f $(docker images -a -q)
AUFS is unable to mount the docker container filesystem.
This is either because: the path is already mounted - or - there's a race condition in docker's interaction with AUFS, due to the large amount of existing volumes.
To solve this, try the following:
restart the docker service or daemon and try again.
check mount for aufs mounted on any paths under /var/lib/docker/aufs/. If found, stop docker, then umount them (need sudo).
example:
mount
none on /var/lib/docker/aufs/mnt/55639da9aa959e88765899ac9dc200ccdf363b2f09ea933370cf4f96051b22b9 type aufs (rw,relatime,si=5abf628bd5735419,dio,dirperm1)
then
sudo umount /var/lib/docker/aufs/mnt/55639da9aa959e88765899ac9dc200ccdf363b2f09ea933370cf4f96051b22b9
If that doesn't work, stop docker, then sudo rm -rf /var/lib/docker/aufs. You will lose any existing stopped containers and all images. But this is just about guaranteed to solve the problem.
Unfortunately on my system I could not resolve this with the above answers. The docker administration kept remembering a certain file in the aufs layer that it couldn't reach anymore. Other solutions didn't work either. So if this is an option for you, you could try the following fix: uninstall/purge docker and docker-engine:
apt-get purge docker docker-engine
Then make sure everything from /var/lib/docker is removed.
rm -rf /var/lib/docker
After that install docker again.
I'm using Raspbian with Raspberry 4
Best way to do it..
Check your docker version with:
sudo docker info and check "Storage Driver"
sudo systemctl stop docker
sudo nano /etc/docker/daemon.json
write this code below and save it
{
"storage-driver": "vfs"
}
sudo systemctl start docker
altought vfs... has a performance issue and could not be the best choice... :)
I just had a similar issue on Lubuntu (Ubuntu 4.15.0-20-generic) with Docker CE 18.03. None of the described options helped.
It appears that latest docker versions use the overlay2 storage driver. However some applications require aufs. Thus a possible fix might be to simply use this docker guide to change the storage driver to aufs (simply replace "overlay2" with "aufs") as in this guide.
I am running a container inside another container(also installed docker in that container) and is trying to create an aufs storage on top of an overlayfs mount, which is not possible. So, I also change the host overlyfs storage to aufs. It's solve my issue. To check storage driver use below command.
docker info
The solution was simply using different driver. I've used aufs in /etc/docker/daemon.json
Here it is
{
"storage-driver": "aufs"
}
For detailed explanation read below documentation.
Docker storage documentation
A similar issue arose while I was using Docker in Windows:
ERROR: Service 'daemon' failed to build: error creating overlay mount
to /var/lib/docker/overlay2/83c98f716020954420e8b89e6074b1af6
1b2b86cd51ac6a54724ed263b3663a2-init/merged: no such file or directory
The problem occurred after having removed a volume from the image's Dockerfile, rebuilding the image and then rebooting the PC. Maybe this is a common cause?
I managed to solve the problem by clicking Docker -> Settings -> Reset -> Reset to factory defaults...
All my images were subsequently lost but that didn't matter for me. I also figured that removing the VM disk image (the path to which can be found under the Advanced tab in Settings) could solve the issue. I haven't tried this approach however.
In windows after a restart, docker machine problem is solved for me.
Use these commands:
docker-machine stop
docker-machine start
docker-compose up
I put this answer also here, as the google search lead me here since the #whitebrow's answer contains what term I searched for in google
ERROR: Service '***' failed to build: error creating overlay mount
to /var/lib/docker/overlay2/***/merged: no such file or directory
In my case, the working workaround surprisingly was to restrict the number of 'RUN' docker building commands/layers, since if the number surpassed 60 layers/commands, it always ended up with that missing 'merged' folder error, no matter what was the contents of the command, even simple command such as RUN ls -la ended up with that error, if the total number of such/any commands was higher than about 60, strange. Merged subfolder was always missing, though even when I automatically generated all the merged subfolders, always was created on the fly a new layer with a new hash, which was missing that subfolder.
I faced the same issue.I resolved it by adding the storage driver to /etc/docker/daemon.json
you can refer this link as well to see other driver options.
Visit https://docs.docker.com/storage/storagedriver/select-storage-driver/
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