I'm starting to learn about docker and I want to run a nextcloud using the docker-compose file.
The docker-compose file I am using. I only specified the volumes which are folders I have created.
version: ‘2’
volumes:
nextcloud:/home/ahmed/Desktop/docker-storage/nextcloud
db:/home/ahmed/Desktop/docker-storage/db
services:
db:
image: mariadb
restart: always
volumes:
- db:/var/lib/mysql
environment:
- MYSQL_ROOT_PASSWORD= anha1985
- MYSQL_PASSWORD= anha1985
- MYSQL_DATABASE=nextcloud
- MYSQL_USER=nextcloud
app:
image: nextcloud
ports:
- 8080:80
links:
- db
volumes:
- nextcloud:/var/www/html
restart: always
The error message that I have is.
ERROR: In file ‘./docker-compose.yml’, volume must be a mapping, not a string.
Please advice me.
The volume section at the top of the compose file is for defining named volumes. If you only have host volumes with an absolute or relative path, then you would only define the volume within each service. For a named volume, you would define it both at the top level and within each service that needs access to the named volume. These two sections, while named similarly, have a different syntax.
See this documentation for the volume section at the top level of the yml file: https://docs.docker.com/compose/compose-file/#volume-configuration-reference
And this documentation applies to the volume section within each service: https://docs.docker.com/compose/compose-file/#volumes
Related
I am using docker to run prometheus, grafana and node exporter. I am trying to use named volumes and I am having some issues with that. My docker-compose code is:
version: "3.7"
volumes:
grafana_ini:
prometheus_data:
grafana_data:
dashboards_data:
services:
grafana:
build: ./grafana
volumes:
- grafana_ini:/etc/grafana/grafana.ini
- grafana_data:/etc/grafana/provisioning/datasources/datasource.yml
- dashboards_data:/etc/grafana/provisioning/dashboards
- ./dashboards/linux_dashboard.json:/etc/grafana/provisioning/dashboards/linux_dashboard.json
ports:
- 3000:3000
links:
- prometheus
prometheus:
build: ./prometheus
volumes:
- prometheus_data:/etc/prometheus/prometheus.yml
ports:
- 9090:9090
node-exporter:
image: prom/node-exporter:latest
container_name: node_exporter
restart: unless-stopped
expose:
- 9100
and my dockerfile for grafana is:
FROM grafana/grafana:latest
COPY ./Ini/grafana.ini /etc/grafana/grafana.ini
COPY datasource.yml /etc/grafana/provisioning/datasources/datasource.yml
COPY ./dashboards/dashboard.yml /etc/grafana/provisioning/dashboards
COPY ./dashboards/server/linux_dashboard.json /etc/grafana/provisioning/dashboards
COPY ./dashboards/server/windows_dashboard.json /etc/grafana/provisioning/dashboards
EXPOSE 3000:3000
and I am getting this error while building it
ERROR: for 2022_grafana_1 Cannot create container for service grafana: source /var/lib/docker/overlay2/4ac5b487fd7fd52491b250c4afaa433801420cd907ac4a70ddb4589fdb99368b/merged/etc/grafana/grafana.ini is not directory
ERROR: for grafana Cannot create container for service grafana: source /var/lib/docker/overlay2/4ac5b487fd7fd52491b250c4afaa433801420cd907ac4a70ddb4589fdb99368b/merged/etc/grafana/grafana.ini is not directory
Can anybody please help me.
It looks like there are some problems with the volume configuration in your Grafana container:
First, I think this was simply a typo in your question:
- grafana_ini:/etc/grafana/grafana.inianticipated location in container
I suspect that you were actually intending this:
- grafana_ini:/etc/grafana/grafana.ini
Which doesn't make any sense: grafana.ini is a file, but a volume is
a directory. Docker won't allow you to mount a directory on top of a
file, hence the error:
ERROR: .../etc/grafana/grafana.ini is not directory
You have the same problem with the grafana_data volume, which you're
attempting to mount on top of datasource.yml:
- grafana_data:/etc/grafana/provisioning/datasources/datasource.yml
I think you may be approaching this configuration in the wrong way;
you may want to read through these documents:
https://grafana.com/docs/grafana/latest/installation/docker/
https://grafana.com/docs/grafana/latest/administration/configure-docker/
https://grafana.com/docs/grafana/latest/administration/provisioning/
It is possible to configure Grafana (and Prometheus!) using only bind
mounts and environment variables (this includes installing plugin,
data sources, and dashboards), so you don't need to build your own
custom images.
Unrelated to this particular problem, there are some other things in
your docker-compose.yml that are worth changing. You should no
longer be using the links directive...
links:
- prometheus
...because Docker maintains DNS for you automatically; your containers
can refer to each other by name with no additional configuration.
I am trying to understand - maybe I already did maybe not - the differences between volumes_from and volumes usage in a docker-compose.yml file. I have read docs already but from there is not so clear to me so I am doing a real exercise.
I have the following setup:
a root directory
a directory named php-apache with a Dockerfile under root
a directory named mongo with a Dockerfile under root
a docker-compose.yml file under root
Note: If it's not clear to you, take a look here and everything exposed down below is right there as well (mongodb-test branch)
At php-apache/Dockerfile I have the following entry:
VOLUME /data /data
At mongo/Dockerfile I have the following entry:
VOLUME /data/db /data/configdb
At docker-compose.yml I have the following:
version: '2'
services:
php-apache:
container_name: "php55-dev"
image: reynierpm/php55-dev
ports:
- "80:80"
environment:
PHP_ERROR_REPORTING: 'E_ALL & ~E_DEPRECATED & ~E_NOTICE'
volumes:
- ~/mmi:/var/www
volumes_from:
- volumes_data
mongo:
container_name: "mongodb"
image: reynierpm/mongodb
ports:
- "27017:27017"
volumes_from:
- volumes_data
volumes_data:
image: tianon/true
volumes:
- ~/data/mongo:/data/db
- ~/data:/data
This is what I am understanding from that setup:
The image reynierpm/php55-dev will expose a /data directory and this will be mapped to ~data:/data in tianon/true image
The image reynierpm/mongodb will expose a /data/db to the outside and mapped to /data/configdb internally then the /data/db is mapped to ~/data/mongo:/data/db in tianon/true image.
Is a mess in my head right now because what do I want to achieve is the following:
Keep mapped the code on the host to the container (this line <path_on_host>:/var/www on docker-compose.yml)
Keep data stored on a local directory in the host
So, it's fine what I am doing? Feel free to made any modification at this setup since I am still learning.
The image reynierpm/php55-dev will expose a /data directory and this will be mapped to ~data:/data in tianon/true image
It's better to say it will mapped to your ~/data on docker host. Please note that there will be a /data/db from the second volume too.
The image reynierpm/mongodb will expose a /data/db to the outside and mapped to /data/configdb internally then the /data/db is mapped to ~/data/mongo:/data/db in tianon/true image.
This container will be the same as php-apache in terms of volumes from
volume_data container.
In case of your objectives:
If your code is in ~/mni/ you are fine. You are mounting mongoDB database directory to php-apache container, I don't think you need that.
You need to create a user defined network for your container connectivity or link containers (legacy). To create user defined network:
docker network create --driver bridge <yournetwork name>
You don't need a DOC. Thats why I removed the third container. I also fixed the unnecessary volume mappings.
Updated Docker file:
version: '2'
services:
php-apache:
container_name: "php55-dev"
image: reynierpm/php55-dev
ports:
- "80:80"
environment:
PHP_ERROR_REPORTING: 'E_ALL & ~E_DEPRECATED & ~E_NOTICE'
volumes:
- ~/mmi:/var/www
volumes_from:
- volumes_data
mongo:
container_name: "mongodb"
image: reynierpm/mongodb
ports:
- "27017:27017"
volumes_from:
- volumes_data
volumes_data:
image: tianon/true
volumes:
- ~/data/mongo:/data/db
- ~/data:/data
networks:
default:
external:
name: <your network name>
Please note you have to call your mongo container from your web application by its name, in your case mongodb.
I am new to docker and developing a project using docker compose. From the documentation I have learned that I should be using data only containers to keep data persistant but I am unable to do so using docker-compose.
Whenever I do docker-compose down it removes the the data from db but by doing docker-compose stop the data is not removed. May be this is because that I am not creating named data volume and docker-compose down hardly removes all the containers. So I tried naming the container but it threw me errors.
Please have a look at my yml file:
version: '2'
services:
data_container:
build: ./data
#volumes:
# - dataVolume:/data
db:
build: ./db
ports:
- "5445:5432"
environment:
- POSTGRES_USER=postgres
- POSTGRES_DB=postgres
# - PGDATA=/var/lib/postgresql/data/pgdata
volumes_from:
# - container:db_bus
- data_container
geoserver:
build: ./geoserver
depends_on:
- db
ports:
- "8004:8080"
volumes:
- ./geoserver/data:/opt/geoserverdata_dir
web:
build: ./web
volumes:
- ./web:/code
ports:
- "8000:8000"
depends_on:
- db
command: python manage.py runserver 0.0.0.0:8000
nginx:
build: ./nginx
ports:
- "83:80"
depends_on:
- web
The Docker file for the data_container is:
FROM stackbrew/busybox:latest
MAINTAINER Tom Offermann <tom#offermann.us>
# Create data directory
RUN mkdir /data
# Create /data volume
VOLUME /data
I tried this but by doing docker-compose down, the data is lost. I tried naming the data_container as you can see the commented line, it threw me this error:
ERROR: Named volume "dataVolume:/data:rw" is used in service "data_container" but no declaration was found in the volumes section.
So right now what I am doing is I created a stand alone data only named container and put that in the volumes_from value of the db. It worked fine and didn't remove any data even after doing docker-compose down.
My queries:
What is the best approach to make containers that can store database's data using the docker-compose and to use them properly ?
My conscious is not agreeing with me on approach that I have opted, the one by creating a stand alone data container. Any thoughts?
docker-compose down
does the following
Stops containers and removes containers, networks, volumes, and images
created by up
So the behaviour you are experiencing is expected.
Use docker-compose stop to shutdown containers created with the docker-compose file but not remove their volumes.
Secondly you don't need the data-container pattern in version 2 of docker compose. So remove that and just use
db:
...
volumes:
- /var/lib/postgresql/data
docker-compose down stops containers but also removes them (with everything: networks, ...).
Use docker-compose stop instead.
I think the best approach to make containers that can store database's data with docker-compose is to use named volumes:
version: '2'
services:
db: #https://hub.docker.com/_/mysql/
image: mysql
volumes:
- "wp-db:/var/lib/mysql:rw"
env_file:
- "./conf/db/mysql.env"
volumes:
wp-db: {}
Here, it will create a named volume called "wp-db" (if it doesn't exist) and mount it in /var/lib/mysql (in read-write mode, the default). This is where the database stores its data (for the mysql image).
If the named volume already exists, it will be used without creating it.
When starting, the mysql image look if there are databases in /var/lib/mysql (your volume) in order to use them.
You can have more information with the docker-compose file reference here:
https://docs.docker.com/compose/compose-file/#/volumes-volume-driver
To store database data make sure your docker-compose.yml will look like
if you want to use Dockerfile
version: '3.1'
services:
php:
build:
context: .
dockerfile: Dockerfile
ports:
- 80:80
volumes:
- ./src:/var/www/html/
db:
image: mysql
command: --default-authentication-plugin=mysql_native_password
restart: always
environment:
MYSQL_ROOT_PASSWORD: example
volumes:
- mysql-data:/var/lib/mysql
adminer:
image: adminer
restart: always
ports:
- 8080:8080
volumes:
mysql-data:
your docker-compose.yml will looks like
if you want to use your image instead of Dockerfile
version: '3.1'
services:
php:
image: php:7.4-apache
ports:
- 80:80
volumes:
- ./src:/var/www/html/
db:
image: mysql
command: --default-authentication-plugin=mysql_native_password
restart: always
environment:
MYSQL_ROOT_PASSWORD: example
volumes:
- mysql-data:/var/lib/mysql
adminer:
image: adminer
restart: always
ports:
- 8080:8080
volumes:
if you want to store or preserve data of mysql then
must remember to add two lines in your docker-compose.yml
volumes:
- mysql-data:/var/lib/mysql
and
volumes:
mysql-data:
after that use this command
docker-compose up -d
now your data will persistent and will not be deleted even after using this command
docker-compose down
extra:- but if you want to delete all data then you will use
docker-compose down -v
to verify or check database data list by using this command
docker volume ls
DRIVER VOLUME NAME
local 35c819179d883cf8a4355ae2ce391844fcaa534cb71dc9a3fd5c6a4ed862b0d4
local 133db2cc48919575fc35457d104cb126b1e7eb3792b8e69249c1cfd20826aac4
local 483d7b8fe09d9e96b483295c6e7e4a9d58443b2321e0862818159ba8cf0e1d39
local 725aa19ad0e864688788576c5f46e1f62dfc8cdf154f243d68fa186da04bc5ec
local de265ce8fc271fc0ae49850650f9d3bf0492b6f58162698c26fce35694e6231c
local phphelloworld_mysql-data
I am looking for guidance on how what is the cleanest way to make a docker-compose.yml version 2 that:
Has container state clearly separated from the container.
Has container state mounted to the host for simplicity (single data point, simply backup /data on the host and you're done). I'm open to be wrong about this, see questions below).
The app is a classic web app with a mysql & redis database for the backend, and with a webserver that is behind a proxy that serves static assets directly. Some details like depends_on, environment variables and the networks are intentionally left out.
Here is what I use at the moment:
version: "2"
services:
proxy:
build:
context: ./apps/nginx
ports:
- "80:80"
- "443:443"
volumes:
- /etc/localtime:/etc/localtime:ro
- ./data/web/assets:/var/www/assets:ro
- ./data/web/puma:/var/run/puma
web:
build:
context: ./apps/rails
volumes:
- /etc/localtime:/etc/localtime:ro
- ./data/web/assets:/srv/app/public/assets
- ./data/web/puma:/var/run/puma
db:
image: mysql:5.7
volumes:
- /etc/localtime:/etc/localtime:ro
- ./data/mysql:/var/lib/mysql
redis:
image: redis
volumes:
- /etc/localtime:/etc/localtime:ro
- ./data/redis:/data
Here is what I plan to use for the next release:
version: "2"
services:
proxy:
build:
context: ./apps/nginx
ports:
- "80:80"
- "443:443"
volumes_from:
- localtime
- web-assets-data:ro
- web-puma-data
web:
build:
context: ./apps/rails
volumes_from:
- localtime
- web-assets-data
- web-puma-data
db:
image: mysql:5.7
volumes_from:
- localtime
- db-data
redis:
image: redis
volumes_from:
- localtime
- redis-data
web-assets-data:
image: ubuntu:14.04
volumes:
- ./data/web/assets:/srv/app/public/assets
web-puma-data:
image: ubuntu:14.04
volumes:
- ./data/web/puma:/var/run/puma
db-data:
image: ubuntu:14.04
volumes:
- ./data/mysql:/var/lib/mysql
redis-data:
image: ubuntu:14.04
volumes:
- ./data/redis:/data
localtime:
image: ubuntu:14.04
volumes:
- /etc/localtime:/etc/localtime:ro
I think the benefits of the new version are:
It's more clear where the data is.
It's easier to share data among multiple containers (no need to remember the exact paths like in the current version).
So, my questions are:
Is it problematic to use different images between the container and it's container-data? for example, should db-data use mysql:5.7 instead of ubuntu:14.04?
Is it correct to say that there's no way of having "data stored at a specific path on the host" with a top level volumes: key?
What are the advantages and inconvenients of using a named volume (with a top-level "volumes" key)? Should I prefer using a named volume over a host mount? Workflow comparisons would be nice.
Is it problematic to use different images between the container and it's container-data
Not at all, this is normal.
Is it correct to say that there's no way of having "data stored at a specific path on the host" with a top level volumes: key?
Correct. The top level volumes key is for named volumes, but you can't name host volumes.
What are the advantages and inconveniences of using a named volume (with a top-level "volumes" key)? Should I prefer using a named volume over a host mount? Workflow comparisons would be nice.
Named volumes let you use volume drivers, so you could have the data stored somewhere other than the local filesystem. However named volumes need to be initialized with data, so you might have to add a script or something to do so.
I'm trying to create a docker-compose.yml file that contains a --volumes-from instruction. Does anyone know the syntax?
I have been looking online for some time now, and it appears that the --volumes-from command is only available as a docker command. I hope I'm wrong.
Aug. 2022:
brandt points out in the comments to the updated docker-compose documentation.
Note August 2017: with docker-compose version 3, regarding volumes:
The top-level volumes key defines a named volume and references it from each service’s volumes list.
This replaces volumes_from in earlier versions of the Compose file format. See Use volumes and Volume Plugins for general information on volumes.
Example:
version: "3.2"
services:
web:
image: nginx:alpine
volumes:
- type: volume
source: mydata
target: /data
volume:
nocopy: true
- type: bind
source: ./static
target: /opt/app/static
db:
image: postgres:latest
volumes:
- "/var/run/postgres/postgres.sock:/var/run/postgres/postgres.sock"
- "dbdata:/var/lib/postgresql/data"
volumes:
mydata:
dbdata:
This example shows a named volume (mydata) being used by the web service, and a bind mount defined for a single service (first path under db service volumes).
The db service also uses a named volume called dbdata (second path under db service volumes), but defines it using the old string format for mounting a named volume.
Named volumes must be listed under the top-level volumes key, as shown.
February 2016:
The docs/compose-file.md mentions:
Mount all of the volumes from another service or container, optionally specifying read-only access(ro) or read-write(rw).
(If no access level is specified, then read-write will be used.)
volumes_from:
- service_name
- service_name:ro
- container:container_name
- container:container_name:rw
For instance (from this issue or this one)
version: "2"
services:
...
db:
image: mongo:3.0.8
volumes_from:
- dbdata
networks:
- back
links:
- dbdata
dbdata:
image: busybox
volumes:
- /data/db