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Host Volume Mount
we already used database with web app but docker containers are ephermal. this means they are losing data once removed or re-started so somewhere need to find data persistent
create docker-compose.yml using following content
version: '3'
services:
db:
image: mysql:latest
restart: always
container_name: myphpapp-db
environment:
MYSQL_ROOT_PASSWORD: somepass
MYSQL_DATABASE: somedatabase
dbclient:
image: mysql:latest
depends_on:
- db
command: mysql -uroot -psomepass -hdb
MYSQL_DATABASE will create an empty database with the name “somedatabase” at first
depends_on waits for the container to start on the other containers
run the command
5-DC-Host-Vol-mount git:(main) ✗ docker compose up -d
[+] Running 3/3
⠿ Network 5-dc-host-vol-mount_default Created 0.1s
⠿ Container myphpapp-db St... 0.3s
⠿ Container 5-dc-host-vol-mount-dbclient-1 Started 0.5s
check docker compose process
5-DC-Host-Vol-mount git:(main) ✗ docker compose ps
NAME IMAGE COMMAND SERVICE CREATED STATUS PORTS
myphpapp-db mysql:latest "docker-entrypoint.s…" db About a minute ago Up About a minute 3306/tcp, 33060/tcp
open mariadb shell
docker compose run --rm dbclient
[+] Running 1/0
⠿ Container myphpapp-db Running 0.0s
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.32 MySQL Community Server - GPL
Copyright (c) 2000, 2023, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
enter following SQL queries
mysql> USE somedatabase;
Database changed
mysql> SHOW TABLES;
Empty set (0.01 sec)
lets create table
mysql> CREATE TABLE mytable (id INT) ;
Query OK, 0 rows affected (0.04 sec)
mysql> SHOW TABLES;
+------------------------+
| Tables_in_somedatabase |
+------------------------+
| mytable |
+------------------------+
1 row in set (0.01 sec)
mysql> exit
stop and remove container
docker-compose stop
[+] Running 2/2
⠿ Container 5-dc-host-vol-mount-dbclient-1 Stopped 0.0s
⠿ Container myphpapp-db Stopped 1.8s
5-DC-Host-Vol-mount git:(main) ✗ docker-compose rm
? Going to remove 5-dc-host-vol-mount-dbclient-1, myphpapp-db Yes
[+] Running 2/0
⠿ Container myphpapp-db Removed 0.0s
⠿ Container 5-dc-host-vol-mount-dbclient-1 Removed 0.0s
➜ 5-DC-Host-Vol-mount git:(main) ✗
lets make data persistent even we remove container ? with volumesa nd a host mounded data directory
mkdir data
lets update docker-compose.yml
version: '3'
services:
db:
image: mysql:latest
restart: always
container_name: myphpapp-db
environment:
MYSQL_ROOT_PASSWORD: somepass
MYSQL_DATABASE: somedatabase
volumes:
- ./data:/var/lib/mysql
dbclient:
image: mysql:latest
depends_on:
- db
command: mysql -uroot -psomepass -hdb
restart docker compose
docker-compose up -d
[+] Running 2/2
⠿ Container myphpapp-db Started 0.4s
⠿ Container 5-dc-host-vol-mount-dbclient-1 Started
0.7s
recreate table
➜ 5-DC-Host-Vol-mount git:(main) ✗ docker compose run --rm dbclient
[+] Running 1/0
⠿ Container myphpapp-db Running 0.0s
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.32 MySQL Community Server - GPL
Copyright (c) 2000, 2023, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> USE somedatabase;
Database changed
mysql> SHOW TABLES;
Empty set (0.01 sec)
CREATE TABLE mytable (id INT) ;
Query OK, 0 rows affected (0.04 sec)
mysql> SHOW TABLES;
+------------------------+
| Tables_in_somedatabase |
+------------------------+
| mytable |
+------------------------+
1 row in set (0.00 sec)
mysql> exit
stop and remove the container
5-DC-Host-Vol-mount git:(main) ✗ docker compose stop
[+] Running 2/2
⠿ Container 5-dc-host-vol-mount-dbclient-1 Stopped 0.0s
⠿ Container myphpapp-db Stopped 2.0s
➜ 5-DC-Host-Vol-mount git:(main) ✗ docker compose rm
? Going to remove 5-dc-host-vol-mount-dbclient-1, myphpapp-db Yes
[+] Running 2/0
⠿ Container myphpapp-db Removed 0.0s
⠿ Container 5-dc-host-vol-mount-dbclient-1 Removed 0.0s
➜ 5-DC-Host-Vol-mount git:(main) ✗
lets start db container again
docker compose run --rm dbclient
[+] Running 1/0
⠿ Container myphpapp-db Running 0.0s
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.32 MySQL Community Server - GPL
Copyright (c) 2000, 2023, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
lets data is persistent or not
USE somedatabase;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> SHOW TABLES;
+------------------------+
| Tables_in_somedatabase |
+------------------------+
| mytable |
+------------------------+
1 row in set (0.00 sec)
mysql> exit
Last updated 03 Jun 2024, 13:43 +0530 .