I am trying to determine why the cloudformation building of application fails when trying to create resources for BackgroundjobsService (Create failed in cloudformation). The only main differences from other services I have built is that it has no exposed ports and I am using ubuntu instead of php-apache image.
Dockerfile (I made it super simply (basically do nothing)
# Pulling Ubuntu image
FROM ubuntu:20.04
docker-compose.yml
services:
background_jobs:
image: 000.dkr.ecr.us-east-1.amazonaws.com/company/job-scheduler
restart: always
env_file: ../.env.${ENV}
build:
context: "."
How I deploy (I verified the enf files exist in the parent directory of job-scheduler).
cd job-scheduler
ENV=dev docker --context default compose build
docker push 000.dkr.ecr.us-east-1.amazonaws.com/company/job-scheduler:latest
ENV=dev docker --context tcetra-dev compose up
I don't know how to find any sort of error logs but the task defination gets created and all my env vars are in there.
So I need rolling-updates with docker on my single node server. Until now, I was using docker-compose but unfortunately, I can't achieve what I need with it. Reading the web, docker-swarm seems to be the way to go.
I have found how to run an app with multiple replicas on a single node using swarm:
docker service create --replicas 3 --name myapp-staging myapp_app:latest
myapp:latest being built from my docker-compose.yml:
version: "3.6"
services:
postgres:
env_file:
- ".env"
image: "postgres:11.0-alpine"
volumes:
- "/var/run/postgresql:/var/run/postgresql"
app:
build: "."
working_dir: /app
depends_on:
- "postgres"
env_file:
- ".env"
command: iex -S mix phx.server
volumes:
- ".:/app"
volumes:
postgres: {}
static:
driver_opts:
device: "tmpfs"
type: "tmpfs"
Unfortunately, this doesn't work since it doesn't get the config from the docker-compose.yml file: .env file, command entry etc.
Searching deeper, I find that using
docker stack deploy -c docker-compose.yml <name>
will create a service using my docker-compose.yml config.
But then I get the following error message:
failed to update service myapp-staging_postgres: Error response from daemon: rpc error: code = InvalidArgument desc = ContainerSpec: image reference must be provided
So it seems I have to use the registry and push my image there so that it works. I understand this need in case of a multiple node architecture, but in my case I don't want to do that. (Carrying images are heavy, I don't want my image to be public, and after all, image is here, so why should I move it to the internet?)
How can I set up my docker service using local image and config written in docker-compose.yml?
I could probably manage my way using docker service create options, but that wouldn't use my docker-compose.yml file so it would not be DRY nor maintainable, which is important to me.
docker-compose is a great tool for developers, it is sad that we have to dive into DevOps tools to achieve such common features as rolling updates. This whole swarm architecture seems too complicated for my needs at this stage.
You don't have to use registeries in your single node setup. you can build your "app" image on your node from a local docker file using this command -cd to the directory of you docker file-
docker build . -t my-app:latest
This will create a local docker image on your node, this image is only visible to your single node which is benefitial in your use case but i wouldn't recommend this in a production setup.
You can now edit the compose file to be:
version: "3.6"
services:
postgres:
env_file:
- ".env"
image: "postgres:11.0-alpine"
volumes:
- "/var/run/postgresql:/var/run/postgresql"
app:
image: "my-app:latest"
depends_on:
- "postgres"
env_file:
- ".env"
volumes:
- ".:/app"
volumes:
postgres: {}
static:
driver_opts:
device: "tmpfs"
type: "tmpfs"
And now you can run your stack from this node and it will use your local app image and benefit from the usage of the image [updates - rollbacks ...etc]
I do have a side note though on your stack file. You are using the same env file for both services, please mind that swarm will look for the ".env" file relative/next to the ".yml" file, so if this is not intentional please revise the location of your env files.
Also on a side note this solution is only feasable on a single node cluster and if you scale your cluster you will have to use a registery and registeries dont have to be public, you can deploy a private registery on your cluster and only your nodes can access it -or you can make it public- the accessibility of your registery is your choice.
Hope this will help with your issue.
Instead of docker images, you can directly use the docker file there. please check the below example.
version: "3.7"
services:
webapp:
build: ./dir
The error is because of compose unable to find an image on the Docker public registry.
Above method should solve your issue.
Basically you need to use docker images in order to make the rolling update to work in docker swarm. Also I would like to clarify that you can host a private registry and use it instead of public one.
Detailed Explanation:
When you try out rolling update how docker swarm works is that it sees whether there is a change in the image which is used for the service if so then docker swarm schedules service updation based on the updation criteria's set up and will work on it.
Let us say there is no change to the image then what happens? Simply docker will not apply the rolling update. Technically you can specify --force flag to make it force update the service but it will just redeploy the service.
Hence create a local repo and store the images into that and use that image name in docker-compose file to be used for a swarm. You can secure the repo by using SSL, user credentials, firewall restrictions which is up to you. Refer this for more details on deploying docker registry server.
Corrections in your compose file:
Since docker stack uses the image to create service you need to specify image: "<image name>" in app service like done in postgres service. AS you have mentioned build instruction image-name is mandatory as docker-compose doesn't know what tho name the image as.Reference.
Registry server is needed if you are going to deploy the application in multi-server. Since you have mentioned it's a single node deployment just having the image pulled/built on the server is enough. But private registry approach is the recommended.
My recommendation is that don't club all the services into a single docker-compose file. The reason is that when you deploy/destroy using docker-compose file all the services will be taken down. This is a kind of tight coupling. Of course, I understand that all the other services depend on DB. in such cases make sure DB service is brought up first before other services.
Instead of specifying the env file make it as a part of Docker file instruction. either copy the env file and source it in entry point or use ENV variable to define it.
Also just an update:
Stack is just to group the services in swarm.
So your compose file should be:
version: "3.6"
services:
postgres:
env_file:
- ".env"
image: "postgres:11.0-alpine"
volumes:
- "/var/run/postgresql:/var/run/postgresql"
app:
build: "."
image: "image-name:tag" #the image built will be tagged as image-name:tag
working_dir: /app # note here I've removed .env file
depends_on:
- "postgres"
command: iex -S mix phx.server
volumes:
- ".:/app"
volumes:
postgres: {}
static:
driver_opts:
device: "tmpfs"
type: "tmpfs"
Dockerfile:
from baseimage:tag
COPY .env /somelocation
# your further instructions go here
RUN ... & \
... & \
... && chmod a+x /somelocation/.env
ENTRYPOINT source /somelocation/.env && ./file-to-run
Alternative Dockerfile:
from baseimage:tag
ENV a $a
ENV b $b
ENV c $c # here a,b,c has to be exported in the shell befire building the image.
ENTRYPOINT ./file-to-run
And you may need to run
docker-compose build
docker-compose push (optional needed to push the image into registry in case registry is used)]
docker stack deploy -c docker-compose.yml <stackname>
NOTE:
Even though you can create the services as mentioned here by #M.Hassan I've explained the ideal recommended way.
I have a docker-compose.yml file which takes the image svka4019/notes2:latest from the docker hub.
However, if I change the image build it and push it, when I run docker-compose it just uses the one it has already downloaded before.
Here is the docker-compose.yml:
springboot-docker-compose-app-container:
image: svka4019/notes2:latest
ports:
- "80:5001"
depends_on:
- friendservice
networks:
- mynet
container_name: base_notes
friendservice:
build: ./Pirmas
command: python app.py
ports:
- 5000:5000
container_name: friend
networks:
- mynet
networks:
mynet:
And the command I use for building and running: docker-compose up --build -d.
For updating the image in docker-hub I use:
docker build -t svka4019/notes2
docker push svka4019/notes2
If I use methods as no-cache it just rebuilds friendService container and skips the base one.
As #DazWilkin pointed out in the comments, using latest tag should be used carefully. Not only can it introduce bugs in your app if latest comes with BC breaks, but it also doesn't indicate that a new update must be performed on your machine if you already have an image 'latest'.
In your case, what you have to do should you want to keep using latest, is to simply call:
docker-compose pull
In case you are building your own image, then you must do:
docker-compose build --pull
The latter will tell docker-compose to first pull the base image before building your custom image.
I want to run docker-compose up on a remote docker daemon:
DOCKER_HOST=tcp://...:2375 docker-compose up
In docker-compose.yml, I have a volume binding to a local file:
version: "3"
services:
nginx:
image: nginx:latest
ports:
- 80:80
volumes:
- ./etc/nginx/nginx.conf:/etc/nginx/nginx.conf:ro
This won't work, as the remote docker daemon will be unable to locate ./etc/nginx/nginx.conf.
What is the best approach to handle this?
Extend the existing docker image by creating your own docker image.
Ref : How to extend existing docker container?
Copy the relevant files (from docker build-context) to appropriate directory and then it will be available in docker image and hence will also be available in remote docker demon as well.
The following command fails, trying to pull image from the Docker Hub:
$ docker-compose up -d
Pulling web-server (web-server:staging)...
ERROR: repository web-server not found: does not exist or no pull access
But I just want to use a local version of the image, which exists:
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
web-server staging b94573990687 7 hours ago 365MB
Why Docker doesn't search among locally stored images?
This is my Docker Compose file:
version: '3'
services:
chat-server:
image: chat-server:staging
ports:
- "8110:8110"
web-server:
image: web-server:staging
ports:
- "80:80"
- "443:443"
- "8009:8009"
- "8443:8443"
and my .env file:
DOCKER_HOST=tcp://***.***.**.**:2376
DOCKER_TLS_VERIFY=true
DOCKER_CERT_PATH=/Users/Victor/Documents/Development/projects/.../target/docker
In general, this should work as you describe it. Tried to reproduce it, but it simply worked...
Folder structure:
.
├── docker-compose.yml
└── Dockerfile
Content of Dockerfile:
FROM alpine
CMD ["echo", "i am groot"]
Build and tag image:
docker build -t groot .
docker tag groot:latest groot:staging
with docker-compose.yml:
version: '3.1'
services:
groot:
image: groot:staging
and start docker-compose:
$ docker-compose up
Creating groot_groot ...
Creating groot_groot_1 ... done
Attaching to groot_groot_1
groot_1 | i am groot
groot_groot_1 exited with code 0
Version >1.23 (2019 and newer)
Easiest way is to change image to build: and reference the Dockerfile in the relative directory, as shown below:
version: '3.0'
services:
custom_1:
build:
context: ./my_dir
dockerfile: Dockerfile
This allows docker-compose to manage the entire build and image orchestration in a single command.
# Rebuild all images
docker-compose build
# Run system
docker-compose up
In your docker-compose.yml, you can specify build: . instead of build: <username>/repo> for local builds (rather than pulling from docker-hub) - I can't verify this yet, but I believe you may be able to do relative paths for multiple services to the docker-compose file.
services:
app:
build: .
Reference: https://github.com/gvilarino/docker-workshop
March-09-2020 EDIT:
(docker version 18.09.9-ce build 039a7df,
dockercompose version 1.24.0, build 0aa59064)
I found that to just create a docker container, you can just docker-compose 'up -d' after tagging the container with a fake local registry server tag (localhost:5000/{image}).
$ docker tag {imagename}:{imagetag} localhost:5000/{imagename}:{imagetag}
You don't need to run the local registry server, but need to change the image url in dockercompose yaml file with the fake local registry server url:
version: '3'
services:
web-server:
image: localhost:5000/{your-image-name} #change from {imagename}:{imagetag} to localhost:5000/{imagename}:{imagetag}
ports:
- "80:80"
from {imagename}:{imagetag} to localhost:5000/{imagename}:{imagetag}
and just up -d
$ docker-compose -f {yamlfile}.yaml up -d
This creates the container if you already have the image (localhost:5000/{imagename}) in your local machine.
Adding to #Tom Saleeba's response,
I still got errors after tagging the container with "/"
(for ex: victor-dombrovsky/docker-image:latest)
It kept looking for the image from remote docker.io server.
registry_address/docker-image
It seems the url before "/" is the registry address and after "/" is the image name. and without "/" provided, docker-compose by default looks for the image from the remote docker.io.
It guess it's a known bug with docker-compose
I finally got it working by running the local registry, pushing the image to the local registry with the registry tag, and pulling the image from the local registry.
$ docker run -d -p 5000:5000 --restart=always --name registry registry:2
$ docker tag your-image-name:latest localhost:5000/your-image-name
$ docker push localhost:5000/your-image-name
and then change the image url in the dockerfile:
version: '3'
services:
chat-server:
image: chat-server:staging
ports:
- "8110:8110"
web-server:
image: localhost:5000/{your-image-name} #####change here
ports:
- "80:80"
- "443:443"
- "8009:8009"
- "8443:8443"
Similarly for the chat-server image.
You might need to change your image tag to have two parts separated by a slash /. So instead of
chat-server:staging
do something like:
victor-dombrovsky/chat-server:staging
I think there's some logic behind Docker tags and "one part" tags are interpreted as official images coming from DockerHub.
For me putting "build: ." did the trick. My working docker compose file looks like this,
version: '3.0'
services:
terraform:
build: .
image: tf:staging
env_file: .env
working_dir: /opt
volumes:
- ~/.aws:/.aws
You have a DOCKER_HOST entry in your .env 👀
From the looks of your .env file you seem to have configured docker-compose to use a remote docker host:
DOCKER_HOST=tcp://***.***.**.**:2376
Moreover, this .env is only loaded by docker-compose, but not docker. So in this situation your docker images output doesn't represent what images are available when running docker-compose.
When running docker-compose you're actually running Docker on the remote host tcp://***.***.**.**:2376, yet when running docker by itself you're running Docker locally.
When you run docker images, you're indeed seeing a list of the images that are stored locally on your machine. But docker-compose up -d is going to attempt to start the containers not on your local machine, but on ***.***.**.**:2376. docker images won't show you what images are available on the remote Docker host unless you set the DOCKER_HOST environment variable, like this for example:
DOCKER_HOST=tcp://***.***.**.**:2376 docker images
Evidently the remote Docker host doesn't have the web-server:staging image stored there, nor is the image available on Docker hub. That's why Docker complains it can't find the image.
Solutions
Run the container locally
If your intention was to run the container locally, then simply remove the DOCKER_HOST=... line from your .env and try again.
Push the image to a repository.
However if you plan on running the image remotely on the given DOCKER_HOST, then you should probably push it to a repository. You can create a free repository at Docker Hub, or you can host your own repository somewhere, and use docker push to push the image there, then make sure your docker-compose.yml referenced the correct repository.
Save the image, load it remotely.
If you don't want to push the image to Docker Hub or host your own repository you can also transfer the image using a combination of docker image save and docker image load:
docker image save web-server:staging | DOCKER_HOST=tcp://***.***.**.**:2376 docker image load
Note that this can take a while for big images, especially on a slow connection.
You can use pull_policy:
image: img:tag
pull_policy: if_not_present
My issue when getting this was that I had built using docker without sudo, and ran docker compose with sudo. Running docker images and sudo docker images gave me two different sets of images, where sudo docker compose up gave me access only to the latter.