Management of Docker Containers Network

docker network ls
docker network inspect bridge

[
    {
        "Name": "bridge",
        "Id": "3c95bc2a2477f0b36d9bd9f932a3809876d68423546c8f393b48e75ccfbfc236",
        "Created": "2021-09-24T16:16:58.135121591Z",
        "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": {},
        "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": {}
    }
]

## create
docker network create --driver bridge sample-net
docker network inspect sample-net | grep Subnet

docker network create --driver bridge --subnet "10.1.0.0/16" test-net
docker network ls

NETWORK ID     NAME         DRIVER    SCOPE
3c95bc2a2477   bridge       bridge    local
7169b9c2108d   host         host      local
b550e8d7e9df   none         null      local
d68a81e0b468   sample-net   bridge    local
12732e64089b   test-net     bridge    local

docker container run --name c1 -it --rm alpine:latest /bin/sh
    # ip addr show eth0
    # ip route
docker container inspect c1

docker container run --name c2 -d alpine:latest ping 127.0.0.1
docker container inspect --format "{{.NetworkSettings.IPAddress}}" c2

docker network inspect bridge
## could see c1 c2 in bridge

docker container run --name c3 -d --network test-net \
    alpine:latest ping 127.0.0.1
docker container run --name c4 -d --network test-net \
    alpine:latest ping 127.0.0.1

docker network inspect test-net
## could see c3 c4 in test-net

docker container exec -it c3 /bin/sh
    ### could ping c4
    # ping c4
    ### but cannot ping c2, neither ip nor hostname
    # ping c2
    # ping 172.17.0.3

docker container run --name c5 -d \
    --network sample-net \
    --network test-net \
    alpine:latest ping 127.0.0.1

docker container rm -f $(docker container ls -aq)
docker network rm sample-net
docker network rm test-net

## or
docker network prune --force

docker container run --rm -it --network host alpine:latest /bin/sh
    ### could see host ip in container
    # ip addr show eth0

docker network create --driver bridge test-net
docker container run --name web -d \
    --network test-net nginx:alpine

## create a new container and put in the same network as web
docker container run -it --rm --network container:web \
    alpine:latest /bin/sh
    # curl localhost

## clean up
docker container rm --force web
docker network rm test-net

## -P means let Docker decide which host port shall be mapped to
docker container run --name web -P -d nginx:alpine
docker container port web
docker container inspect web | grep HostPort

## user define port mapping
docker container run --name web2 -p 8910:80 -d nginx:alpine