Docker Volumes: Persisting Data - docker

I have a docker-compose file below where I have a mariadb with volume. Each time i perform a docker-compose pull and docker-compose up -d i lose the data after updating the image
mariadb:
image: bitnami/mariadb:latest
container_name: mariadb-db
ports:
- 3303:3306
environment:
- "MARIADB_ROOT_PASSWORD=password"
- "MARIADB_EXTRA_FLAGS=--max-connect-errors=1000 --max_connections=300"
- "MARIADB_DATABASE=mydb"
restart: on-failure
volumes:
- mariadb-data:/var/lib/mysql
volumes:
mariadb-data:
How do i make the data persistent?

According to the readme, the database inside the container is at /bitnami/mariadb. This isn't standard, rather a feature of bitnami/mariadb image. It would be /var/lib/mysql if you had used an official one.
Thus, either change the path inside the container:
image: bitnami/mariadb:latest
volumes:
- mariadb-data:/bitnami/mariadb
or use the default path with an official image:
image: mariadb:latest
volumes:
- mariadb-data:/var/lib/mysql

Related

Docker volume not getting deleted

I have an application where I need to reset the database (wipe it completely).
I ran all the commands I could find
docker system prune
docker system prune -a -f
docker volume prune
Using docker volume ls, I copied the volume ID and then ran
docker volume rm "the volume id"
When I do docker system df nothing is shown anymore. However, once I run my app again
docker-compose up --build
the database still contains old values.
What am I doing wrong?
EDIT here is my compose file
version: "3"
services:
nftapi:
env_file:
- .env
build:
context: .
ports:
- '5000:5000'
depends_on:
- postgres
networks:
- postgres
extra_hosts:
- "host.docker.internal:host-gateway"
restart: always
postgres:
container_name: postgres
image: postgres:latest
ports:
- "5432:5432"
volumes:
- /data/postgres:/var/lib/postgresql/data
env_file:
- docker.env
networks:
- postgres
pgadmin:
links:
- postgres:postgres
container_name: pgadmin
image: dpage/pgadmin4
ports:
- "8080:80"
env_file:
- docker.env
networks:
- postgres
networks:
postgres:
driver: bridge
It seems the database in your config is mapped to a directory on your host system:
volumes:
- /data/postgres:/var/lib/postgresql/data
so the data in the containers /var/lib/postgresql/data is read from and written to your local /data/postgres directory.
If you want to delete it you should empty out that directory. (Or move it until you are sure that you can delete it)

Update in-docker-compose container with new env_file

I have the following docker-compose configuration:
version: '2'
services:
nginx:
image: 'nginx:latest'
expose:
- '80'
- '8080'
container_name: nginx
ports:
- '80:80'
- '8080:8080'
volumes:
- '/home/ubuntu/nginx.conf:/etc/nginx/nginx.conf'
networks:
- default
restart: always
inmates:
image: 'xxx/inmates:mysql'
container_name: 'inmates'
expose:
- '3000'
env_file: './inmates.env'
volumes:
- inmates_documents_images:/data
- inmates_logs:/logs.log
networks:
- default
restart: always
we19:
image: 'xxx/we19:dev'
container_name: 'we19'
expose:
- '3000'
env_file: './we19.env'
volumes:
- we19_logs:/logs.log
networks:
- default
restart: always
desktop:
image: 'xxx/desktop:dev'
container_name: 'desktop'
expose:
- '3000'
env_file: './desktop.env'
volumes:
- desktop_logs:/logs.log
networks:
- default
restart: always
volumes:
inmates_documents_images:
inmates_logs:
desktop_logs:
we19_logs:
Assume I did docker-compose up -d --buiild.
Now the 4 containers (services) are runnig.
Now, I want to update ./desktop.env file with new content. Is there any possible way to reset only desktop container with the new env file? Or docker-compose restart is neccessary?
Basically I'm trying to restart only desktop container with the new env file but keep all 3 others container up running without restarting them.
Extract from docker-compose up --help
[...]
If there are existing containers for a service, and the service's configuration or image was changed after the container's creation, docker-compose up picks up the changes by stopping and recreating the containers (preserving mounted volumes). To prevent Compose from picking up changes, use the --no-recreate flag.
[...]
Usage: up [options] [--scale SERVICE=NUM...] [SERVICE...]
[...]
The following command should do the trick in your case.
docker-compose up -d desktop
If not, see the documentation for other options you can use to meet your exact requirement (e.g. --force-recreate, --renew-anon-volumes, ...)

Possible to access files from a different docker image within a container?

I'm trying to set up a docker-compose file for running Apache Guacamole.
The compose file has 3 services, 2 for guacamole itself and 1 database image. The problem is that the database has to be initialized before the guacamole container can use it, but the files to initialize the database are in the guacamole image. The solution I came up with is this:
version: "3"
services:
init:
image: guacamole/guacamole:latest
command: ["/bin/sh", "-c", "cp /opt/guacamole/postgresql/schema/*.sql /init/" ]
volumes:
- dbinit:/init
database:
image: postgres:latest
restart: unless-stopped
volumes:
- dbinit:/docker-entrypoint-initdb.d
- dbdata:/var/lib/postgresql/data
environment:
POSTGRES_USER: guac
POSTGRES_PASSWORD: guac
depends_on:
- init
guacd:
image: guacamole/guacd:latest
restart: unless-stopped
guacamole:
image: guacamole/guacamole:latest
restart: unless-stopped
ports:
- "8080:8080"
environment:
GUACD_HOSTNAME: guacd
POSTGRES_HOSTNAME: database
POSTGRES_DATABASE: guac
POSTGRES_USER: guac
POSTGRES_PASSWORD: guac
depends_on:
- database
- guacd
volumes:
dbinit:
dbdata:
So I have one container whose job is to copy the database initialization files into a volume and then I mount that volume in the database. The problem is that this creates a race condition and is ugly. Is there some elegant solution for this? Is it possible to mount the files from the guacamole image into the database container? I would rather avoid having an extra sql file with the docker-compose file.
Thanks in advance!

Docker Compose - How to store database data?

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

Increasing docker volume size using docker-compose

I'm working on deploying a Flask web app with Docker (using docker-compose). Users upload files which can be particularly big (>1GB). My question is -- do I have to be worried about the container running out of space? I've read that containers have a default max size of 10GB, and I will definitely exceed that quickly. If I create a volume in the "flask-app/uploads" directory where all the files are stored, does that solve my problem or is the volume just another container with the same size limitations? Is there any way I can just store everything that gets uploaded to "flask-app/uploads" to the host machine so nothing get written to the container?
Here is my docker-compose.yml file for reference:
web:
restart: always
build: ./web
expose:
- "8000"
links:
- postgres:postgres
volumes:
- /usr/src/flask-app/static
- /usr/src/flask-app/uploads (??)
env_file: .env
command: /usr/local/bin/gunicorn -w 2 -b :8000 app:app
nginx:
restart: always
build: ./nginx/
ports:
- "80:80"
volumes:
- /www/static
volumes_from:
- web
links:
- web:web
data:
restart: always
image: postgres:latest
volumes:
- /var/lib/postgresql
command: "true"
postgres:
restart: always
image: postgres:latest
volumes_from:
- data
ports:
- "5432:5432"
Yes, this is a common practice, you can use a host volume. Change the volume line to - ./uploads:/usr/src/flask-app/uploads.

Resources