docker - how to keep the data after docker down and up? - docker

Question

i run this command to pull images, up services
docker-compose -f dc-all.yml up
but i noticed the data keep in the images e.g. database data is gone once i down and up the docker
the command i tried to down the docker.
docker-compose -f dc-all.yml down
what is the best practice to keep the data?
or how to keep docker running without restart? e.g. windows restart does not
sample yml file
networks:
test:
services:
db:
networks:
- pm
image: microsoft/mssql-server-linux:2017-latest
container_name: mssql
hostname: mssql
volumes:
- ./.db:/var/opt/mssql/
- /var/opt/mssql/data
- ./sqlinit.sql:/scripts/sqlinit.sql
ports:
- 8010:1433
environment:
- ACCEPT_EULA=Y
- MSSQL_SA_PASSWORD=Test123!
command:
- /bin/bash
- -c
- |
# Launch MSSQL and send to background
/opt/mssql/bin/sqlservr &
# Wait for it to be available
echo "Waiting for MS SQL to be available"
/opt/mssql-tools/bin/sqlcmd -l 30 -S mssql -h-1 -V1 -U sa -P Test123! -Q "SET NOCOUNT ON SELECT \"YAY WE ARE UP\" , ##servername"
is_up=$$?
while [ $$is_up -ne 0 ] ; do
echo -e $$(date)
/opt/mssql-tools/bin/sqlcmd -l 30 -S mssql -h-1 -V1 -U sa -P Test123! -Q "SET NOCOUNT ON SELECT \"YAY WE ARE UP\" , ##servername"
is_up=$$?
sleep 5
done
# Run every script in /scripts
# TODO set a flag so that this is only done once on creation,
# and not every time the container runs
#for foo in /scripts/*.sql
/opt/mssql-tools/bin/sqlcmd -S mssql -U sa -P Test123! -l 30 -e -i /scripts/sqlinit.sql
#done
# So that the container doesn't shut down, sleep this thread
sleep infinity
zookeeper:
networks:
- pm
image: wurstmeister/zookeeper
hostname: zookeeper
container_name: zookeeper
ports:
- "2181:2181"
environment:
ZOOKEEPER_CLIENT_PORT: 2181
ZOOKEEPER_TICK_TIME: 2000
ALLOW_ANONYMOUS_LOGIN: 1
kafka:
networks:
- pm
image: wurstmeister/kafka
hostname: kafka
container_name: kafka
depends_on:
- zookeeper
ports:
- "9092:9092"
environment:
KAFKA_ZOOKEEPER_CONNECT: 'zookeeper:2181'
KAFKA_AUTO_CREATE_TOPICS_ENABLE: 'true'
ALLOW_PLAINTEXT_LISTENER: 'yes'
KAFKA_ADVERTISED_HOST_NAME: kafka
schema-registry:
networks:
- pm
image: confluentinc/cp-schema-registry:5.2.1
hostname: schema-registry
container_name: schema-registry
depends_on:
- zookeeper
- kafka
ports:
- "8081:8081"
environment:
SCHEMA_REGISTRY_HOST_NAME: 'schema-registry'
SCHEMA_REGISTRY_KAFKASTORE_CONNECTION_URL: 'zookeeper:2181'
rest-proxy:
networks:
- pm
image: confluentinc/cp-kafka-rest:5.2.1
depends_on:
- zookeeper
- kafka
- schema-registry
ports:
- "8082:8082"
hostname: rest-proxy
container_name: rest-proxy
environment:
KAFKA_REST_HOST_NAME: 'rest-proxy'
KAFKA_REST_BOOTSTRAP_SERVERS: 'kafka:9092'
KAFKA_REST_LISTENERS: "http://rest-proxy:8082"
KAFKA_REST_SCHEMA_REGISTRY_URL: 'http://schema-registry:8081'
KAFKA_REST_ZOOKEEPER_CONNECT: 'zookeeper:2181'
katalon:
networks:
- pm
image: katalonstudio/katalon:latest
container_name: katalon
hostname: katalon
depends_on:
- db
- zookeeper
- kafka
- schema-registry
- rest-proxy
volumes:
- ../katalon-service:/katalon/katalon/source
entrypoint: katalon-execute.sh
command:
- -browserType=Web Service
- -retry=0
- -statusDelay=15
- -testSuitePath=Test Suites/TS_IntegrationTestSuites_SQL

Answer 1

You can either mount the docker host directory as below in compose -
volumes:
- /data:/app
Using above, all the data generated inside your /app directory will show up in /data of your docker host.
OR
Use docker logical volumes -
volumes:
- mydata:/data
volumes:
mydata:
Above will create a new volume which can be shared with other services and will not be destroyed once you do a docker-compose down. The data on this logical volume stays on your host itself. You can get the directory details using below command -
docker inspect mydata
Sample output -
[
{
"CreatedAt": "2018-09-24T05:40:37Z",
"Driver": "local",
"Labels": {
"com.docker.compose.project": "mydata",
"com.docker.compose.version": "1.22.0",
"com.docker.compose.volume": "data"
},
"Mountpoint": "/var/lib/docker/volumes/mydata/_data",
"Name": "mydata",
"Options": null,
"Scope": "local"
}
]
Mountpoint is where your data exists on the host.
Ref - https://docs.docker.com/compose/compose-file/#volume-configuration-reference

Answer 2

You use volumes like you do in Docker. See the full doc for all the details.
but basically you want:
services:
some_service:
volumes:
- $PWD/data:/path/to/data