docker 容器中访问宿主机或者其他容器

1. 首先可以用命令查看桥接模式下的所有网络

docker network inspect bridge

[
    {
        "Name": "bridge",
        "Id": "587fe8337798f3f26e590f9a6b8f67d98641077412924e5c7a48f088cd27f48d",
        "Created": "2020-06-28T16:07:26.189913852+08:00",
        "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": {
            "057c865e764d2965e6bb65161d14f42956755921058e844eadb8f60e854bb5b9": {
                "Name": "some-redmine2",
                "EndpointID": "1fc4f99867419fd5c6cf76cba7b8d60601b1ddcb6e6ae8b97c137db21c3f76d4",
                "MacAddress": "02:42:ac:11:00:03",
                "IPv4Address": "172.17.0.3/16",
                "IPv6Address": ""
            },
            "08e9b1bcc06bff2a14de1ed167fdba16a814b8fdd2fe50f83ca7b5ca92808298": {
                "Name": "pgadmin4",
                "EndpointID": "601b35110e30272fda12e7c8f3a2c62fe15752b7322019a1da87971c79a07ebe",
                "MacAddress": "02:42:ac:11:00:04",
                "IPv4Address": "172.17.0.4/16",
                "IPv6Address": ""
            },
            "2290b60f3ac6fc6796beb5ad59838f6c8af5258d8a44213bfb0470eb03767b89": {
                "Name": "db",
                "EndpointID": "b69debde9c98562686bb21dc28a7df064579619dd5cf43265077ee5fc413c206",
                "MacAddress": "02:42:ac:11:00:02",
                "IPv4Address": "172.17.0.2/16",
                "IPv6Address": ""
            },
            "88f3588039234bad40b020e000fe33d70265741d091fd057d95512fd0c01beb1": {
                "Name": "odoo12-test",
                "EndpointID": "5496fc9922090053943641c97f6ef7ed1a2811cc12666f8c89fffccdf85b9dab",
                "MacAddress": "02:42:ac:11:00:05",
                "IPv4Address": "172.17.0.5/16",
                "IPv6Address": ""
            },
            "96282a47e1cd91c9f8b1ecb41eb8e92f79dcd310aefef5b0fc34aeac369031e2": {
                "Name": "vscode",
                "EndpointID": "e10e2bbc423ef21d5a6538656ff27a66bc4d9d1707437d41e62c992573903969",
                "MacAddress": "02:42:ac:11:00:0a",
                "IPv4Address": "172.17.0.10/16",
                "IPv6Address": ""
            },
            "e39fa67e7a7e11e97b0305c9ca7c73e94c4b27bc5446414b553ad46cf6ebb1d1": {
                "Name": "odoo14",
                "EndpointID": "07220b6cc2ce860d6ce6781fc3409f4498df9339bd082606a00c39053966d8bd",
                "MacAddress": "02:42:ac:11:00:07",
                "IPv4Address": "172.17.0.7/16",
                "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": {}
    }
]

2. 可以得到的信息:
   • docker 网络名称:bridge
   • 子网掩码:172.17.0.0/16
   • 在该网段下的所有容器名称,以及对应的IP地址
3. 在同一个网段下,容器之间的连接就畅通无阻了.
4. 宿主机的主机号默认为1,即 172.17.0.1