I want to get the manifest file of a docker image but unfortunately I cannot use docker. Is it possible to download it using curl?
The equivalent command with docker would be:
docker manifest inspect <image_name>
Related
I have upgraded to a new server and am trying to migrate my Docker containers over.
Most of the containers that I am running are made up of multiple image files
I used the docker commit appID appname command to create my own images of each
and then saved all of the images to a .tar file using
docker save image1 image2 image3 > backup.tar
Then transfered the tar file to my new server and ran
docker load -i backup.tar
Which added the backup images as wel as associated volumes on to my new server...
The problem I now have is, there are 7 image files and I cannot find a way to create the docker container using these image files.
When I use the YAML file and change the image to represent the locally stored image rather than the image from the docker repository, it still pulls the image from the repository
Is there a recommended way to launch the container from the local images exported from the tar file?
Maybe you can use something like this:
docker save -o backup.tar $(docker images --format "{{.Repository}}:{{.Tag}}")
Alternatively:
docker save $(docker images --format "{{.Repository}}:{{.Tag}}") > backup.tar
This will tag your images with the name and tags.
Once you do
docker load -i backup.tar
and perform:
docker images -a
you will be able to use the images based on the name:tag
I have docker desktop on C drive also as WSL. I started ubuntu terminal on F drive in specific folder by making it starting location. After executing docker run -d -p 80:80 docker/getting-started it says me ```unable to find image <image_name> and starts container.
After that when container is created I can see it in docker.
It also creates image but the problem is I can't find it and where image and container are stored.
How can I find files of docker and so on and create, run container with its image on F drive in wsl folder (in this example)?
well i can't understand your problem well, but here an answer for your question
It also creates image but the problem is I can't find it and where image and container are stored.
to find images downloaded locally
run
docker images
to find the metadata which include path of stored image
docker inspect <image_name>
Now I have such a requirement，firstly I need export a container’s filesystem as a tar archive, then I need push this tar to my own docker registry.So could I push a tar file which is exported by using docker export image_name to my private registry.Before this I only know I could push a local image to registry by using docker push image_name. Thanks!
If you don't want to use any external tools, you can use a combination of:
docker image load --input image.tar.gz # this will output the original image name
docker image tag original-registry.example.org/original-image-name:0.0.1 new-registry.example.com/new-image-name:0.0.1
docker push new-registry.example.com/new-image-name
The crane tool seems to have this functionality:
crane pull - Pull a remote image by reference and store its contents in a tarball
crane push - Push image contents as a tarball to a remote registry
I've just released the following library:
https://pypi.org/project/dockertarpusher/0.16/
I've also struggled with volume the docker socket into container that needs only to repush tar image, so that was the reason for this library
The three tools I know of for working with registries without a docker engine are crane from Google, skopeo from RedHat, and regclient from myself.
The workflow that's needed is to extract the tar, push each layer and config, and then push the manifests. OCI's distribution-spec includes details on the registry API, but realize that the authentication doesn't have a spec over there (at least not yet), and there are different tar files whether you are talking about a docker export, docker save, or an OCI layout. There's also whether the tar file has been compressed.
For the latter two formats, you can use regctl image import from the regclient project. E.g.:
regctl image import localhost:5000/project:tag image.tar
Or to go the other way and create an export (that is a merge of the docker save and OCI layouts):
regctl image export localhost:5000/project:tag image.tar
I have created a container using the following command: docker container run -i ubuntu. However, when I try to run a command within the container, such as cd, I get the following error: bash: line 1: cd: $'bin\r': No such file or directory. What could be the issue?
When you docker run an image, or use an image in a Dockerfile FROM line, or name an image: in a Docker Compose setup, Docker first checks to see if you have that image locally. If you have that image, Docker just uses it without checking Docker Hub or the other upstream registry.
Meanwhile, you can docker build or docker tag an image with any name you want...even a name that matches an official Docker Hub image.
You mention in a comment that you at some point did run docker build -t ubuntu .... That replaces the ubuntu image with what you built, so when you later docker run ubuntu, it's running your modified image and not the official Docker Hub Ubuntu image.
This is straightforward to fix. If you
docker rmi ubuntu
it will delete your local (modified) copy, and the next time you use it, Docker will automatically pull it from Docker Hub. It should also work to
# Explicitly get the Docker Hub copy of the image
docker pull ubuntu
# Build a custom image, pulling whatever's in the FROM line
docker build --pull -t my/image .
(You can also hit this in a Docker Compose setup if you specify both image: and build:; this instructs Compose on an explicit name to use for the built image. You do not need to repeat the FROM line in image:, and it causes trouble if you do. The resolution is the same as described above. I might leave image: out entirely unless you're planning to push the image to a registry.)
I have a docker image. I want to analyze the docker image history, for this I can use docker image history command in the docker installed environment.
But when am working in a Openshift cluster, I may not have the access to the docker command here. So here I want get the docker history command result for the given image.
So basically I have a docker image and I don't have docker installed there. In this case how can we get the history of that docker image?
Can anyone please help me on this?
You can get the registry info either via curl or skopeo inspect. But the rest of the metadata is stored inside the image itself so you do have to download at least the final layer.