Docker Network

建立兩容器

$ docker container run -d --rm --name box1 busybox /bin/sh -c "while true; do sleep 3600; done"
$ docker container run -d --rm --name box2 busybox /bin/sh -c "while true; do sleep 3600; done"
$ docker container ls
CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS     NAMES
4f3303c84e53   busybox   "/bin/sh -c 'while t…"   49 minutes ago   Up 49 minutes             box2
03494b034694   busybox   "/bin/sh -c 'while t…"   49 minutes ago   Up 49 minutes             box1

容器間的通信->使用bridge

$ docker network ls
NETWORK ID     NAME      DRIVER    SCOPE
1847e179a316   bridge    bridge    local
a647a4ad0b4f   host      host      local
fbd81b56c009   none      null      local
$ docker network inspect bridge
[
    {
        "Name": "bridge",
        "Id": "1847e179a316ee5219c951c2c21cf2c787d431d1ffb3ef621b8f0d1edd197b24",
        "Created": "2021-07-01T15:28:09.265408946Z",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": [
                {
                    "Subnet": "172.17.0.0/16",
                    "Gateway": "172.17.0.1"
                }
            ]
        },
        "Internal": false,
        "Attachable": false,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {
            "03494b034694982fa085cc4052b6c7b8b9c046f9d5f85f30e3a9e716fad20741": {
                "Name": "box1",
                "EndpointID": "072160448becebb7c9c333dce9bbdf7601a92b1d3e7a5820b8b35976cf4fd6ff",
                "MacAddress": "02:42:ac:11:00:02",
                "IPv4Address": "172.17.0.2/16",
                "IPv6Address": ""
            },
            "4f3303c84e5391ea37db664fd08683b01decdadae636aaa1bfd7bb9669cbd8de": {
                "Name": "box2",
                "EndpointID": "4cf0f635d4273066acd3075ec775e6fa405034f94b88c1bcacdaae847612f2c5",
                "MacAddress": "02:42:ac:11:00:03",
                "IPv4Address": "172.17.0.3/16",
                "IPv6Address": ""
            }
        },
        "Options": {
            "com.docker.network.bridge.default_bridge": "true",
            "com.docker.network.bridge.enable_icc": "true",
            "com.docker.network.bridge.enable_ip_masquerade": "true",
            "com.docker.network.bridge.host_binding_ipv4": "0.0.0.0",
            "com.docker.network.bridge.name": "docker0",
            "com.docker.network.driver.mtu": "1500"
        },
        "Labels": {}
    }
]

"IPAM": {
    "Driver": "default",
    "Options": null,
    "Config": [
    {
         "Subnet": "172.17.0.0/16",
        "Gateway": "172.17.0.1"
    }
    ]
},

"com.docker.network.bridge.name": "docker0",

# brctl 顯示bridge tool
$ brctl show
bridge name     bridge id               STP enabled     interfaces
docker0         8000.0242759468cf       no              veth8c9bb82
                                                        vethd8f9afb

容器對外通訊->iptables nat

$ ip route
default via 10.0.2.2 dev eth0 proto dhcp metric 100
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15 metric 100
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1
192.168.200.0/24 dev eth1 proto kernel scope link src 192.168.200.10 metric 101

$ sudo iptables --list -t nat
Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination
DOCKER     all  --  anywhere             anywhere             ADDRTYPE match dst-type LOCAL

Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
DOCKER     all  --  anywhere            !loopback/8           ADDRTYPE match dst-type LOCAL

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination
MASQUERADE  all  --  172.17.0.0/16        anywhere

Chain DOCKER (2 references)
target     prot opt source               destination
RETURN     all  --  anywhere             anywhere

docker network create --help

docker network create -d {driver} --gateway {gateway} --subnet {subnet} {name}
docker network create -d bridge --gateway 127.200.0.1 -subnet 172.200.0.0/16 demo

[tomcat@docker-qc html-doc]$ docker network create -d bridge mybridge
65c5ba6cbea2fa677e8dd0623a510f3461e24ccac196b7374fc5e8d03803ec9e

[tomcat@docker-qc html-doc]$  docker network ls
NETWORK ID          NAME                DRIVER              SCOPE
780162e5fe57        bridge              bridge              local
3c5b59c8a708        host                host                local
65c5ba6cbea2        mybridge            bridge              local

[tomcat@docker-qc html-doc]$ docker network inspect mybridge
[
    {
        "Name": "mybridge",
        "Id": "65c5ba6cbea2fa677e8dd0623a510f3461e24ccac196b7374fc5e8d03803ec9e",
        "Created": "2022-01-18T18:44:39.95740673+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": {},
        "Options": {},
        "Labels": {}
    }
]

# 建立連接mybridge的container (--network 不設定會用預設的)
$ docker container run -d --rm --name box3 --network mybridge busybox /bin/sh -c "while true; do sleep 3600; done"
# 既有container 連接mybridge
$ docker network connect mybridge box1
# container 中斷 mybridge
$ docker network disconnect mybridge box1