docker - 我的 Docker 容器没有 IP 地址。为什么？

Question

我使用命令启动了一个 rethinkDB docker 容器

docker pull rethinkdb:2.3
docker run --rm --name rethinkdb -v /srv/rethinkdb:/data --net host rethinkdb:2.3 rethinkdb --bind all --cache-size 8192 --no-update-check

现在容器已成功启动。我做了 docker ps

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
f288961ef376        rethinkdb:2.3       "rethinkdb --bind ..."   9 minutes ago       Up 9 minutes                            rethinkdb
1f71722698ae        sorccu/adb:latest   "/sbin/tini -- adb..."   14 minutes ago      Up 14 minutes                           adbd

现在我想找出这个容器的 IP 地址。所以我做到了

docker inspect --format '{{ .NetworkSettings.IPAddress }}' f288961ef376

它什么也没给我。我找不到这个容器的 IP 地址。

我通过转到 http://localhost:8080 检查了 rethinkDB 配置页面是否已启动，我看到它已启动并正在运行。

为什么这个容器没有 IP 地址？

docker inspect的输出如下

[
    {
        "Id": "f288961ef376531c97d2264cb8ef3c6077a6a75107905d6a47734303adfcb117",
        "Created": "2017-05-05T11:13:45.382460184Z",
        "Path": "rethinkdb",
        "Args": [
            "--bind",
            "all",
            "--cache-size",
            "8192",
            "--no-update-check"
        ],
        "State": {
            "Status": "running",
            "Running": true,
            "Paused": false,
            "Restarting": false,
            "OOMKilled": false,
            "Dead": false,
            "Pid": 8157,
            "ExitCode": 0,
            "Error": "",
            "StartedAt": "2017-05-05T11:13:45.774035358Z",
            "FinishedAt": "0001-01-01T00:00:00Z"
        },
        "Image": "sha256:c5ed876750b40cde4725ea9eb9d8503f4d1419a2f23ac2ef8e4cc1d535e2c3a2",
        "ResolvConfPath": "/var/lib/docker/containers/f288961ef376531c97d2264cb8ef3c6077a6a75107905d6a47734303adfcb117/resolv.conf",
        "HostnamePath": "/var/lib/docker/containers/f288961ef376531c97d2264cb8ef3c6077a6a75107905d6a47734303adfcb117/hostname",
        "HostsPath": "/var/lib/docker/containers/f288961ef376531c97d2264cb8ef3c6077a6a75107905d6a47734303adfcb117/hosts",
        "LogPath": "/var/lib/docker/containers/f288961ef376531c97d2264cb8ef3c6077a6a75107905d6a47734303adfcb117/f288961ef376531c97d2264cb8ef3c6077a6a75107905d6a47734303adfcb117-json.log",
        "Name": "/rethinkdb",
        "RestartCount": 0,
        "Driver": "aufs",
        "MountLabel": "",
        "ProcessLabel": "",
        "AppArmorProfile": "docker-default",
        "ExecIDs": null,
        "HostConfig": {
            "Binds": [
                "/srv/rethinkdb:/data"
            ],
            "ContainerIDFile": "",
            "LogConfig": {
                "Type": "json-file",
                "Config": {}
            },
            "NetworkMode": "host",
            "PortBindings": {},
            "RestartPolicy": {
                "Name": "no",
                "MaximumRetryCount": 0
            },
            "AutoRemove": true,
            "VolumeDriver": "",
            "VolumesFrom": null,
            "CapAdd": null,
            "CapDrop": null,
            "Dns": [],
            "DnsOptions": [],
            "DnsSearch": [],
            "ExtraHosts": null,
            "GroupAdd": null,
            "IpcMode": "",
            "Cgroup": "",
            "Links": null,
            "OomScoreAdj": 0,
            "PidMode": "",
            "Privileged": false,
            "PublishAllPorts": false,
            "ReadonlyRootfs": false,
            "SecurityOpt": null,
            "UTSMode": "",
            "UsernsMode": "",
            "ShmSize": 67108864,
            "Runtime": "runc",
            "ConsoleSize": [
                0,
                0
            ],
            "Isolation": "",
            "CpuShares": 0,
            "Memory": 0,
            "NanoCpus": 0,
            "CgroupParent": "",
            "BlkioWeight": 0,
            "BlkioWeightDevice": null,
            "BlkioDeviceReadBps": null,
            "BlkioDeviceWriteBps": null,
            "BlkioDeviceReadIOps": null,
            "BlkioDeviceWriteIOps": null,
            "CpuPeriod": 0,
            "CpuQuota": 0,
            "CpuRealtimePeriod": 0,
            "CpuRealtimeRuntime": 0,
            "CpusetCpus": "",
            "CpusetMems": "",
            "Devices": [],
            "DeviceCgroupRules": null,
            "DiskQuota": 0,
            "KernelMemory": 0,
            "MemoryReservation": 0,
            "MemorySwap": 0,
            "MemorySwappiness": -1,
            "OomKillDisable": false,
            "PidsLimit": 0,
            "Ulimits": null,
            "CpuCount": 0,
            "CpuPercent": 0,
            "IOMaximumIOps": 0,
            "IOMaximumBandwidth": 0
        },
        "GraphDriver": {
            "Data": null,
            "Name": "aufs"
        },
        "Mounts": [
            {
                "Type": "bind",
                "Source": "/srv/rethinkdb",
                "Destination": "/data",
                "Mode": "",
                "RW": true,
                "Propagation": ""
            }
        ],
        "Config": {
            "Hostname": "dev-machine",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": true,
            "AttachStderr": true,
            "ExposedPorts": {
                "28015/tcp": {},
                "29015/tcp": {},
                "8080/tcp": {}
            },
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "RETHINKDB_PACKAGE_VERSION=2.3.5~0jessie"
            ],
            "Cmd": [
                "rethinkdb",
                "--bind",
                "all",
                "--cache-size",
                "8192",
                "--no-update-check"
            ],
            "Image": "rethinkdb:2.3",
            "Volumes": {
                "/data": {}
            },
            "WorkingDir": "/data",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": {}
        },
        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "bd17bf8e1663ff18f6674a1a3a1665c4e1bf65283d358ffc97dc238ef4a79088",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {},
            "SandboxKey": "/var/run/docker/netns/default",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "",
            "Gateway": "",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "",
            "IPPrefixLen": 0,
            "IPv6Gateway": "",
            "MacAddress": "",
            "Networks": {
                "host": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "30b6150968580d33aae0e45f7d850b9e67ae2aa29e1bb837ca4fa74f2b0d4d42",
                    "EndpointID": "05e93ec514ee6694e57d344f3e4362252104347c3cc48c607708d125715ed6ec",
                    "Gateway": "",
                    "IPAddress": "",
                    "IPPrefixLen": 0,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": ""
                }
            }
        }
    }
]

Answer 1

您正在使用 --net host 选项启动您的容器，这意味着您的容器将在您的主机网络上运行。查看 here了解更多信息。因此，您的容器将可以在您的主机的 IP 上访问。

一个非常基本的例子:

$ docker run --net=host -d jenkins

这将在您的真实主机网络上运行 jenkins。因此，当您打开防火墙(jenkins 在 8080 上运行)时，您将立即访问您的容器。于是我打开了防火墙:

$ sudo iptables -I INPUT 5 -p tcp -m tcp --dport 8080 -j ACCEPT

我使用 ifconfig 检查我的 eth0(主机网络)的真实 IP。 (我在虚拟机上做这个)。它是 inet 192.168.140.7。我在浏览器中进入 192.168.140.7:8080 并看到 Jenkins 。所以你的容器没有自己的IP。它在您的主机网络和主机 IP 上运行。

如果您保留 --net host 选项，容器将在默认的 docker bridge 网络中创建，范围为 "172.17.0.0/16"。现在您的容器将从该网络范围内获得一个 IP。要从外部访问容器，您必须在主机网络上映射端口(请参阅更多信息)。您可以使用 -p 选项来做到这一点。

所以对于 Jenkins 的例子:

$ docker run -d -p 8888:8080 jenkins

当我执行 docker inspect 我看到:

"IPAddress": "172.17.0.4",

所以我的容器在 172.17.0.4:8080 的桥接网络中运行。现在使用 -p 选项，我将桥接网络的端口 8080 映射到主机网络的 8888 上:所以 host-IP:8888。现在它可以从外部访问了。