How can we make nginx image available in my local/private repository in kubernetes?
Lets say i am using nginx image tag version x.x. I have tested it in my dev and test env and want to move it to prod.
What if the image is not present in nginx repository?
Is there a way to pull the x.x version of nginx to our local/private repository?
There is a high risk if the image is not available. So it would be helpful if anyone guide me how we handle this.
If you have docker installed in your machine, pull docker image
$ docker pull nginx:x.x
Now, you can't use this local docker image inside Kubernetes. You need to do additional thing
Push this image into your docker registry in cloud.
$ docker tag nginx:x.x <your-registry>/nginx:x.x
$ docker push <your-registry>/nginx:x.x
And then use <your-registry>/nginx:x.x from your registry.
Related
I was wondering is it possible to use cached docker images in gitlab registry for gitlab-ci?
for example, I want to use node:16.3.0-alpine docker image, can I cache it in my gitlab registry and pull it from that and speed up my gitlab ci instead of pulling it from docker hub?
Yes, GitLab's dependency proxy features allow you to configure GitLab as a "pull through cache". This is also beneficial for working around rate limits of upstream sources like dockerhub.
It should be faster in most cases to use the dependency proxy, but not necessarily so. It's possible that dockerhub can be more performant than a small self-hosted server, for example. GitLab runners are also remote with respect to the registry and not necessarily any "closer" to the GitLab registry than any other registry over the internet. So, keep that in mind.
As a side note, the absolute fastest way to retrieve cached images is to self-host your GitLab runners and hold images directly on the host. That way, when jobs start, if the image already exists on the host, the job will start immediately because it does not need to pull the image (depending on your pull configuration). (that is, assuming you're using images in the image: declaration for your job)
I'm using a corporate Gitlab instance where for some reason the Dependency Proxy feature has been disabled. The other option you have is to create a new Docker image on your local machine, then push it into the Container Registry of your personal Gitlab project.
# First create a one-line Dockerfile containing "FROM node:16.3.0-alpine"
docker pull node:16.3.0-alpine
docker build . -t registry.example.com/group/project/image
docker login registry.example.com -u <username> -p <token>
docker push registry.example.com/group/project/image
where the image tag should be constructed based on the example given on your project's private Container Registry page.
Now in your CI job, you just change image: node:16.3.0-alpine to image: registry.example.com/group/project/image. You may have to run the docker login command (using a deploy token for credentials, see Settings -> Repository) in the before_script section -- I think maybe newer versions of Gitlab will have the runner authenticate to the private Container Registry using system credentials, but that could vary depending on how it's configured.
I have some services running when I run docker-compose up command. Now I want to make an image from the current environment and share it with docker hub so that every time I can use docker pull/run my_own_image command from the docker hub.
Is there any way to do that?
Pretty much anything that you can do with images or containers with Docker, you can do with Compose. In your case, since you can push your custom image to your Docker Hub registry using docker image push (or docker push) command, you can do the same with Compose.
As for Compose, you use docker-compose push (no surprises there – consistency between APIs/CLIs).
Tip: when in doubt, use --help. It's the best way (next to Google) to explore CLI. If not sure what are available commands/options for Compose, just type docker-compose --help. If you want to see available options for push command (for example), use docker-compose push --help.
I have something on my mind that is bugging me. When running docker images I see a list of my local images I have in my docker environment. When pulling Images I pull it from a registry and more specific pull the specified tag managed by the repository.
so there is the registry as the big hub to store all image
repositories
and the repository is storing commits/tagged versions of a specific image
But what is docker images then? It's a registry as well isn't it? It holds all images that I've built locally or pulled.
If my claim is valid:
How does it comply with running a private registry (mentioned here https://docs.docker.com/registry/deploying/)
Running this docker run -d -p 5000:5000 --restart=always --name registry registry:2
Would deploy this new registry into my docker images...
So now I have a registry within my registry... registception?
What is the difference besides the custom registry is deployable?
Its not a local image registry as other questions have pointed. It is an image cache. The purpose of the image cache is to avoid having every time to download the same image whenever you do a docker run.
docker images simply lists all the cached images on the machine. Whenever there is newer image on the registry, the image(some layers) are downloaded and cached when doing docker pull .... Also, when a layer exists in the local cache, docker tells you that, example:
Step 2/2 : CMD /bin/bash
---> Using cache
On the other hand, a docker registry is a central repository to store images. It provide a remote api to pull and push images. The local image cache does not have this feature. Images in the local cache are read and stored used local docker commands that simply read files under /var/lib/docker/...
To make things clear, think of Docker remote registries (such as Docker Hub) as the remote Git repositories. You pull Docker images (like git repositories) that you need and you play with it.
Like remote Git repositories such as GitHub\BitBucket, Docker registries are also public and private. Public registries are for public usage and open-source projects. Examples include in like Docker Hub. Where as private registries are for organizational use or for your own. Examples for private registries include Azure Container Registry, EC2 Container Registry etc.
The official Docker Registry image is just a Docker registry image for your own system, you can't share them with others unless you have a server or a public Internet IP address. Think of it as Bonobo Private Git Server for Windows.
Your local image registry as you mentioned are all those images that you have build locally or pulled from a registry public or private you can see it like a local cache of images that you can re use without download or rebuild each time.
Running the registry what actually does is to spin up a server that implements the Docker Registry API which allows users to push, pull, delete and handles the storage of this images and their layers. See it like a central repository like npm, nexus
For example if you run the registry in your.registry.com:5000
You can do things like
docker build -t your.registry.com:5000/my-image:tag .
docker push your.registry.com:5000/my-image:tag
So others that have access to your server can pull it
docker pull your.registry.com:5000/my-image:tag
A colleague find out Docker and want to use it for our project. I start to use Docker for test. After reading an article about Docker swarm I want to test it.
I have installed 3 VM (ubuntu server 14.04) with docker and swarm. I followed some How To ( http://blog.remmelt.com/2014/12/07/docker-swarm-setup/ and http://devopscube.com/docker-tutorial-getting-started-with-docker-swarm/). My cluster work. I can launch for exemple a basic apache container (the image was pull in the Docker hub) but I want to use my own image (an apache server with my web site).
I tested to load an image (after save it in a .tar) but this option isn't supported by the clustering mode, same thing with the import option.
So my question is : Can I use my own image without to push it in the Docker hub and how I do this ?
If your own image is based on a Dockerfile that you build you can execute the build command on your project while targeting the swarm.
However if the image wasn't built, but created manually you need to have a registry in between that you can push to, either docker hub or some other registry solution like https://github.com/docker/docker-registry
I was wondering if there was a way to clone images from a local server.
The servers running containers will be hosted behind a bandwidth constrained connection. It would be great if there was a way to pull given containers for one server and then pull from that initial local server to update the containers on the remaining servers.
You could pull those images you want, give hem a new tag, and put them in your own registry.
For instance, let's say you pulled down the official registry image and stood it up at myregistry.internal.mycompany.com. Now, if you wanted to have a CentOS image available for all of your servers but didn't want to pull them all from the official repo (incurring the bandwitch charges) then you could pull a CentOS image (let's say centos:latest - docker pull centos) and then give that image a new tag, like this:
docker tag centos:latest myregistry.internal.mycompany.com/centos:latest
Now from your other servers you just pull 'myregistry.internal.mycompany.com/centos:latest'
Setting up your own repo is really easy as a docker container itself. You can pull the image and learn more at https://registry.hub.docker.com/_/registry/
I think you have a few options. If what you actually want to manage is images rather than containers:
You could set up a private Docker registry, and then push to/pull from that local repository. This may ultimately be the easiest if that is something that you want to do fairly often, because you're just using standard docker push/docker pull commands.
You could use docker save to save images on one server and docker load to load the images on another server.
If you are actually trying to move containers around:
You could use docker export on one server and docker import on another server.