cat docker-compose.yml 
version: '3'
services: 
 test1:
  image: busybox:latest     # 镜像为 busybox
  entrypoint:          # 容器启动后执行 top 命令，使容器没法立即退出
   - top
  networks:
   backend:     # 使用指定的网络 backend, 并且设置网络别名为 test1，
    aliases:    # 设置网络别名后，可以在其他容器中 ping test1 访问到该容器
     - test1

 test2:
  image: busybox:latest
  entrypoint:
   - top
  networks:
   backend:
    aliases:
     - test2

networks:
 backend:

docker-compose up -d

docker ps -a
CONTAINER ID    IMAGE        COMMAND       CREATED       STATUS       PORTS        NAMES
4d05ceb2088d    busybox:latest   "top"        5 seconds ago    Up 4 seconds              ibaboss_test2_1
f4ccafa24664    busybox:latest   "top"        5 seconds ago    Up 4 seconds              ibaboss_test1_1

docker exec -it 4d05ceb2088d /bin/sh
/ # ping test1
PING test1 (172.19.0.2): 56 data bytes
64 bytes from 172.19.0.2: seq=0 ttl=64 time=0.061 ms
64 bytes from 172.19.0.2: seq=1 ttl=64 time=0.062 ms

ping ibaboss_test1_1
PING ibaboss_test1_1 (172.19.0.2): 56 data bytes
64 bytes from 172.19.0.2: seq=0 ttl=64 time=0.045 ms
64 bytes from 172.19.0.2: seq=1 ttl=64 time=0.056 ms
64 bytes from 172.19.0.2: seq=2 ttl=64 time=0.061 ms

# 在网络中可以通过 容器名字或者网络的别名 进行通信

container_name: app
cat docker-compose_v1.yml 
version: '3'
services: 
 test1:
  image: busybox:latest
  entrypoint:
   - top
  container_name: test1
  networks:
   - backend

 test2:
  image: busybox:latest
  entrypoint:
   - top
  container_name: test2
  networks:
   - backend

networks:
 backend:

docker-compose -f docker-compose_v1.yml up -d

docker ps -a
CONTAINER ID    IMAGE        COMMAND       CREATED       STATUS       PORTS        NAMES
132859fc77c2    busybox:latest   "top"        About a minute ago  Up About a minute            test2
cd0a78dc9bd4    busybox:latest   "top"        About a minute ago  Up About a minute            test1

docker exec -it 132859fc77c2 ping test1
PING test1 (172.19.0.2): 56 data bytes
64 bytes from 172.19.0.2: seq=0 ttl=64 time=0.070 ms
64 bytes from 172.19.0.2: seq=1 ttl=64 time=0.068 ms
64 bytes from 172.19.0.2: seq=2 ttl=64 time=0.059 ms

version: '3.3'
services:
nginx:
image: "lnp_php"
# container_name: "lnmp_nginx"
ports:
- "80:80"
- "443:443"
- "3306:3306"
expose:
- "3306"
volumes:
- /home/www/php:/home/www:rw
# depends_on:
# - mysql
# links:
# - mysql
mysql:
image: "mysql"
# container_name: "lnmp_mysql"
# ports:
# - "3306:3306"
# expose:
# - "3306"
volumes:
- /home/docker/conf/mysql_w:/etc/mysql:rw
environment:
- MYSQL_ROOT_PASSWORD=123456
depends_on:
- nginx
network_mode: "service:nginx"