CentOS 7
Sponsored Link

Docker : Use Docker Compose2015/12/17
 
To Install Docker Compose, it's easy to configure and run multiple containers as a Docker application.
[1] Install Docker Compose.
[root@dlp ~]#
curl -L https://github.com/docker/compose/releases/download/1.27.4/docker-compose-$(uname -s)-$(uname -m) -o /usr/local/bin/docker-compose
[root@dlp ~]#
chmod 755 /usr/local/bin/docker-compose
[root@dlp ~]#
docker-compose --version

docker-compose version 1.27.4, build 40524192
[2] For example, Configure an application that has Web and DB services with Docker Compose.
# define Web service container

[root@dlp ~]#
vi Dockerfile 
FROM centos
MAINTAINER ServerWorld <admin@srv.world>

RUN yum -y install nginx

EXPOSE 80
CMD ["/usr/sbin/nginx", "-g", "daemon off;"]
# define application configuration

[root@dlp ~]#
vi docker-compose.yml 
version: '3'
services:
  db:
    image: mariadb
    volumes:
      - /var/lib/docker/disk01:/var/lib/mysql
    environment:
      MYSQL_ROOT_PASSWORD: password
      MYSQL_USER: cent
      MYSQL_PASSWORD: password
      MYSQL_DATABASE: cent_db
    ports:
      - "3306:3306"
  web:
    build: .
    ports:
      - "80:80"
    volumes:
      - /var/lib/docker/disk02:/usr/share/nginx/html
# buid and run

[root@dlp ~]#
docker-compose up -d 

Creating network "root_default" with the default driver
Building web
Step 1/5 : FROM centos
 ---> 300e315adb2f
Step 2/5 : MAINTAINER ServerWorld <admin@srv.world>
 ---> Using cache
 ---> 3b1af99319a3
Step 3/5 : RUN yum -y install nginx
 ---> Running in 55c877260a34

.....
.....

Creating root_web_1 ... done
Creating root_db_1  ... done
[root@dlp ~]#
docker ps 

CONTAINER ID   IMAGE      COMMAND                  CREATED         STATUS         PORTS                                       NAMES
fa286dd17bdb   mariadb    "docker-entrypoint.s…"   9 seconds ago   Up 6 seconds   0.0.0.0:3306->3306/tcp, :::3306->3306/tcp   root_db_1
8a0181ea0c35   root_web   "/usr/sbin/nginx -g …"   9 seconds ago   Up 6 seconds   0.0.0.0:80->80/tcp, :::80->80/tcp           root_web_1
# verify accesses

[root@dlp ~]#
mysql -h 127.0.0.1 -u root -p -e "show variables like 'hostname';" 

Enter password:
+---------------+--------------+
| Variable_name | Value        |
+---------------+--------------+
| hostname      | fa286dd17bdb |
+---------------+--------------+
[root@dlp ~]#
mysql -h 127.0.0.1 -u cent -p -e "show databases;" 

Enter password:
+--------------------+
| Database           |
+--------------------+
| cent_db            |
| information_schema |
+--------------------+
[root@dlp ~]#
echo "Hello Docker Compose World" > /var/lib/docker/disk02/index.html

[root@dlp ~]#
curl 127.0.0.1

Hello Docker Compose World
[3] Other basic operations of Docker Compose are follows.
# verify state of containers

[root@dlp ~]#
docker-compose ps 

   Name                 Command               State                    Ports
----------------------------------------------------------------------------------------------
root_db_1    docker-entrypoint.sh mysqld      Up      0.0.0.0:3306->3306/tcp,:::3306->3306/tcp
root_web_1   /usr/sbin/nginx -g daemon off;   Up      0.0.0.0:80->80/tcp,:::80->80/tcp
# show logs of containers

[root@dlp ~]#
docker-compose logs 

Attaching to root_db_1, root_web_1
db_1   | 2021-05-24 04:13:36+00:00 [Note] [Entrypoint]: Entrypoint script for MariaDB Server 1:10.5.10+maria~focal started.
db_1   | 2021-05-24 04:13:36+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
db_1   | 2021-05-24 04:13:36+00:00 [Note] [Entrypoint]: Entrypoint script for MariaDB Server 1:10.5.10+maria~focal started.
.....
.....
db_1   | 2021-05-24  4:13:47 0 [Note] mysqld: ready for connections.
db_1   | Version: '10.5.10-MariaDB-1:10.5.10+maria~focal'  socket: '/run/mysqld/mysqld.sock'  port: 3306  mariadb.org binary distribution
# run any commands inside a container

# container name is just the one set in [docker-compose.yml]

[root@dlp ~]#
docker-compose exec db /bin/bash 

root@fa286dd17bdb:/#
# stop application and also shutdown all containers

[root@dlp ~]#
docker-compose stop 

Stopping root_web_1 ... done
Stopping root_db_1  ... done
# start a service alone in application

# if set dependency, other container starts

[root@dlp ~]#
docker-compose up -d web 

Starting root_web_1 ... done
[root@dlp ~]#
docker-compose ps 

   Name                 Command               State                 Ports
---------------------------------------------------------------------------------------
root_db_1    docker-entrypoint.sh mysqld      Exit 0
root_web_1   /usr/sbin/nginx -g daemon off;   Up       0.0.0.0:80->80/tcp,:::80->80/tcp
# remove all containers in application

# if a container is running, it won't be removed

[root@dlp ~]#
docker-compose rm 

Going to remove root_db_1
Are you sure? [yN] y
Removing root_db_1 ... done
Matched Content