本文我们简单说一下，容器之间是怎么相互他通讯的，假设我们一个容器只有php，一个容器只有nginx，一个容器只有mysql或者redis，我们想要php容器去链接mysql或者redis应该怎么做呢
首先，如果我们在没有指定网络的情况一下，一般容器是会使用默认的网络，也就是bridge ,
我们看下docker网络列表
[root@work home]# docker network list
NETWORK ID NAME DRIVER SCOPE
5927b735123e bridge bridge local
c71ab2fd1bcf host host local
707911944ab8 none null local
然后启动3个docker
[root@work home]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4e18e2880b5e centos:7.6.1810 "/bin/bash" 27 minutes ago Up 27 minutes centostest
fbfd416582a0 nginx:latest "/docker-entrypoint.…" 37 minutes ago Up 37 minutes 80/tcp nginxtest
c3e05f45b3a1 php:7.4.27-fpm "docker-php-entrypoi…" 48 minutes ago Up 48 minutes 9000/tcp test
我们随意进入一个容器里面
[root@work home]# docker exec -it centostest /bin/bash
[root@4e18e2880b5e /]# ping nginxtest
ping: nginxtest: Name or service not known
发现是无法识别的，我们可以通过一下操作来创建一个网络（因为默认网络不带dns）
#创建网络
docker network create jinan
#将容器nginxtest加入到网络中
docker network connect jinan nginxtest
#将容器centostest加入到网络中
docker network connect jinan centostest
#将容器test加入到网络中
docker network connect jinan test
现在可以先看下网络列表
[root@work home]# docker network list
NETWORK ID NAME DRIVER SCOPE
5927b735123e bridge bridge local
c71ab2fd1bcf host host local
b48d23bb5492 jinan bridge local
707911944ab8 none null local
可以查看下使用该网络的有哪些容器
[root@work home]# docker network inspect jinan
[
{
"Name": "jinan",
"Id": "b48d23bb5492d6fa2b02042dabbca54715d4e0070b8104bff6ece718f8b5a29d",
"Created": "2022-01-14T17:57:39.983008369+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "172.18.0.0/16",
"Gateway": "172.18.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"4e18e2880b5e31b6f1cc4f1fbcf837a52f311e8d5b71d516f964701ae0fba7ad": {
"Name": "centostest",
"EndpointID": "9ce4e741a8ac48f5d58d85819da2b68dc8cce7820a714ba39f0daa7e555e198f",
"MacAddress": "02:42:ac:12:00:03",
"IPv4Address": "172.18.0.3/16",
"IPv6Address": ""
},
"c3e05f45b3a16d77d98c57feaff9e5a9fd7e3ca6e4a9d4af0853fc2538cab82f": {
"Name": "test",
"EndpointID": "6594cd35fa6594027ea229ee93f32e39c1e0bd02d8050c65af8a0c98e319671a",
"MacAddress": "02:42:ac:12:00:04",
"IPv4Address": "172.18.0.4/16",
"IPv6Address": ""
},
"fbfd416582a011079813442553b3b9e5bfdc97aeda4d1da5100adaa0813c681e": {
"Name": "nginxtest",
"EndpointID": "701387ca6762be60cef0702ff0dc0e4c51230f7d80c2dae3870b64224eae8ec6",
"MacAddress": "02:42:ac:12:00:02",
"IPv4Address": "172.18.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]
从Containers可以看到刚加入的三个容器都在这个网络里
进入任意一个容器中
[root@work home]# docker exec -it centostest /bin/bash
[root@4e18e2880b5e /]# ping nginxtest
PING nginxtest (172.18.0.2) 56(84) bytes of data.
64 bytes from nginxtest.jinan (172.18.0.2): icmp_seq=1 ttl=64 time=0.043 ms
64 bytes from nginxtest.jinan (172.18.0.2): icmp_seq=2 ttl=64 time=0.050 ms
64 bytes from nginxtest.jinan (172.18.0.2): icmp_seq=3 ttl=64 time=0.051 ms
64 bytes from nginxtest.jinan (172.18.0.2): icmp_seq=4 ttl=64 time=0.061 ms
64 bytes from nginxtest.jinan (172.18.0.2): icmp_seq=5 ttl=64 time=0.052 ms
OK 已经实现了容器之间的通讯了，已经创建了网络的，以后启动容器可以通过 --network=jinan来直接加入到jinan网络中
