Ubuntu 上的 Docker 无法连接到本地主机，但可以连接到其 IP

我运行的是 Ubuntu 18.04

$ uname -r
5.3.0-46-generic

我已经安装了docker

$ docker --version
Docker version 19.03.8, build afacb8b7f0

我有一个简单的 docker 映像，它公开端口 80。生成它的 Dockerfile 是

FROM mcr.microsoft.com/dotnet/core/aspnet:3.1
COPY publish .
EXPOSE 80
ENTRYPOINT ["dotnet", "SampleWebApp.dll"]

当我为此图像运行容器时，我可以看到以下内容：

$ docker run myimage:latest -p 8080:80
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://[::]:80
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
      Content root path: /

如果我看到容器正在运行：

$ docker ps
CONTAINER ID        IMAGE                                                                              COMMAND                  CREATED             STATUS              PORTS               NAMES
6f5bea7b329d        registry.gitlab.com/whatever/myimage:latest   "dotnet SampleWebApp…"   4 seconds ago       Up 2 seconds        80/tcp              dreamy_leavitt

所以我可以看到它正在端口 80/tcp 上运行。 不知道为什么它不在端口 8080 上运行，这是我想映射它的地方。

另外，http://[::]:80 http://%5B::%5D:80看起来很混乱。我读过一些关于 IPv6 的内容。不知道这会产生什么后果，也不知道为什么普通的 IPv4 不起作用。

我的界面信息：

$ ifconfig
docker0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.17.0.1  netmask 255.255.0.0  broadcast 172.17.255.255
        inet6 fe80::42:71ff:fe7f:305  prefixlen 64  scopeid 0x20<link>
        ether 02:42:71:7f:03:05  txqueuelen 0  (Ethernet)
        RX packets 131843  bytes 105630866 (105.6 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 201439  bytes 268197990 (268.1 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

enp3s0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 1c:1b:0d:a4:83:16  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 118628  bytes 17999594 (17.9 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 118628  bytes 17999594 (17.9 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

vethca5fd09: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet6 fe80::3c56:d6ff:fe0c:846  prefixlen 64  scopeid 0x20<link>
        ether 3e:56:d6:0c:08:46  txqueuelen 0  (Ethernet)
        RX packets 7  bytes 533 (533.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 52  bytes 7342 (7.3 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

wlp6s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.1.135  netmask 255.255.255.0  broadcast 192.168.1.255
        inet6 fe80::8a58:c682:3833:3bb1  prefixlen 64  scopeid 0x20<link>
        ether e4:be:ed:4f:0f:21  txqueuelen 1000  (Ethernet)
        RX packets 519710  bytes 524989683 (524.9 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 439859  bytes 165781721 (165.7 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

所以..docker接口似乎有地址172.17.0.1.

但是我无法使用以下网址访问我的容器：

$ curl http://localhost:8080
curl: (7) Failed to connect to localhost port 8080: Connection refused

$ curl http://localhost:80
curl: (7) Failed to connect to localhost port 80: Connection refused

$ curl http://0.0.0.0:80
curl: (7) Failed to connect to 0.0.0.0 port 80: Connection refused

$ curl http://0.0.0.0:8080
curl: (7) Failed to connect to 0.0.0.0 port 8080: Connection refused

$ curl http://172.17.0.1:8080
curl: (7) Failed to connect to 172.17.0.1 port 8080: Connection refused

$ curl http://172.17.0.1:80
curl: (7) Failed to connect to 172.17.0.1 port 80: Connection refused

$ curl http://127.0.0.1:8080
curl: (7) Failed to connect to 127.0.0.1 port 8080: Connection refused

$ curl http://127.0.0.1:80
curl: (7) Failed to connect to 127.0.0.1 port 80: Connection refused

所以无法访问使用localhost, 127.0.0.1或 docker 接口 IP。

If I inspect容器：

sasw@Z3:~$ docker inspect 6f5bea7b329d
[
    {
        "Id": "6f5bea7b329d05bcb534953745f376da9c7efbe54de5532f8648b618152b722a",
        "Created": "2020-04-20T13:06:37.883347676Z",
        "Path": "dotnet",
        "Args": [
            "SampleWebApp.dll",
            "-p",
            "8080:80"
        ],
        "State": {
            "Status": "running",
            "Running": true,
            "Paused": false,
            "Restarting": false,
            "OOMKilled": false,
            "Dead": false,
            "Pid": 30636,
            "ExitCode": 0,
            "Error": "",
            "StartedAt": "2020-04-20T13:06:38.295411125Z",
            "FinishedAt": "0001-01-01T00:00:00Z"
        },
        "Image": "sha256:e00403d6c5eb3ccbe3c5c7b6ec8cf8289158e4c9fbe6ff5872ea932e69d60f38",
        "ResolvConfPath": "/var/lib/docker/containers/6f5bea7b329d05bcb534953745f376da9c7efbe54de5532f8648b618152b722a/resolv.conf",
        "HostnamePath": "/var/lib/docker/containers/6f5bea7b329d05bcb534953745f376da9c7efbe54de5532f8648b618152b722a/hostname",
        "HostsPath": "/var/lib/docker/containers/6f5bea7b329d05bcb534953745f376da9c7efbe54de5532f8648b618152b722a/hosts",
        "LogPath": "/var/lib/docker/containers/6f5bea7b329d05bcb534953745f376da9c7efbe54de5532f8648b618152b722a/6f5bea7b329d05bcb534953745f376da9c7efbe54de5532f8648b618152b722a-json.log",
        "Name": "/dreamy_leavitt",
        "RestartCount": 0,
        "Driver": "overlay2",
        "Platform": "linux",
        "MountLabel": "",
        "ProcessLabel": "",
        "AppArmorProfile": "docker-default",
        "ExecIDs": null,
        "HostConfig": {
            "Binds": null,
            "ContainerIDFile": "",
            "LogConfig": {
                "Type": "json-file",
                "Config": {}
            },
            "NetworkMode": "default",
            "PortBindings": {},
            "RestartPolicy": {
                "Name": "no",
                "MaximumRetryCount": 0
            },
            "AutoRemove": false,
            "VolumeDriver": "",
            "VolumesFrom": null,
            "CapAdd": null,
            "CapDrop": null,
            "Capabilities": null,
            "Dns": [],
            "DnsOptions": [],
            "DnsSearch": [],
            "ExtraHosts": null,
            "GroupAdd": null,
            "IpcMode": "private",
            "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": [],
            "BlkioDeviceReadBps": null,
            "BlkioDeviceWriteBps": null,
            "BlkioDeviceReadIOps": null,
            "BlkioDeviceWriteIOps": null,
            "CpuPeriod": 0,
            "CpuQuota": 0,
            "CpuRealtimePeriod": 0,
            "CpuRealtimeRuntime": 0,
            "CpusetCpus": "",
            "CpusetMems": "",
            "Devices": [],
            "DeviceCgroupRules": null,
            "DeviceRequests": null,
            "KernelMemory": 0,
            "KernelMemoryTCP": 0,
            "MemoryReservation": 0,
            "MemorySwap": 0,
            "MemorySwappiness": null,
            "OomKillDisable": false,
            "PidsLimit": null,
            "Ulimits": null,
            "CpuCount": 0,
            "CpuPercent": 0,
            "IOMaximumIOps": 0,
            "IOMaximumBandwidth": 0,
            "MaskedPaths": [
                "/proc/asound",
                "/proc/acpi",
                "/proc/kcore",
                "/proc/keys",
                "/proc/latency_stats",
                "/proc/timer_list",
                "/proc/timer_stats",
                "/proc/sched_debug",
                "/proc/scsi",
                "/sys/firmware"
            ],
            "ReadonlyPaths": [
                "/proc/bus",
                "/proc/fs",
                "/proc/irq",
                "/proc/sys",
                "/proc/sysrq-trigger"
            ]
        },
        "GraphDriver": {
            "Data": {
                "LowerDir": "/var/lib/docker/overlay2/8f56c544522ccb6556358601706cb900c405c19b47e54c25d8b3dac979100e5b-init/diff:/var/lib/docker/overlay2/81bfee49e33d9761a6ca78dfd6f3f9a54a9333b4d4fc9986e8084f6b45232f04/diff:/var/lib/docker/overlay2/c2add2cb2d687126c6826c7dd9e1c85be1473a53d6b878554aa87615701344a0/diff:/var/lib/docker/overlay2/ebd0b92c5111423fb8d1219f757e41013a1473bdbe5cf3553cecbd4337f76766/diff:/var/lib/docker/overlay2/9197af6ebe4c70f0a84c7c267b1ba069aa710d917abe9fb3fee13320a17ab765/diff:/var/lib/docker/overlay2/1f463e8667b6eecc7c251ac05316b8d5d32840bff13d9f5cb7853c88e6f1f40e/diff:/var/lib/docker/overlay2/b7c9450f53334bef02f50cc854b33140b97f4ff3d2343b3fcac7b20f647c454e/diff",
                "MergedDir": "/var/lib/docker/overlay2/8f56c544522ccb6556358601706cb900c405c19b47e54c25d8b3dac979100e5b/merged",
                "UpperDir": "/var/lib/docker/overlay2/8f56c544522ccb6556358601706cb900c405c19b47e54c25d8b3dac979100e5b/diff",
                "WorkDir": "/var/lib/docker/overlay2/8f56c544522ccb6556358601706cb900c405c19b47e54c25d8b3dac979100e5b/work"
            },
            "Name": "overlay2"
        },
        "Mounts": [],
        "Config": {
            "Hostname": "6f5bea7b329d",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": true,
            "AttachStderr": true,
            "ExposedPorts": {
                "80/tcp": {}
            },
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "ASPNETCORE_URLS=http://+:80",
                "DOTNET_RUNNING_IN_CONTAINER=true"
            ],
            "Cmd": [
                "-p",
                "8080:80"
            ],
            "Image": "registry.gitlab.com/ddd-malaga/continuous-deployment-gitlab-docker-dotnet:latest",
            "Volumes": null,
            "WorkingDir": "",
            "Entrypoint": [
                "dotnet",
                "SampleWebApp.dll"
            ],
            "OnBuild": null,
            "Labels": {}
        },
        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "4e53bd2bc6cb83b7c0cba9fcdf07eb564a11ca6b955514670ba3f464aa0a96b7",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {
                "80/tcp": null
            },
            "SandboxKey": "/var/run/docker/netns/4e53bd2bc6cb",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "83976112bb202b79880777563cd1b06ef27781fd288b210b19fb499e3bf51c90",
            "Gateway": "172.17.0.1",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "172.17.0.2",
            "IPPrefixLen": 16,
            "IPv6Gateway": "",
            "MacAddress": "02:42:ac:11:00:02",
            "Networks": {
                "bridge": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "7589efd57cea8d2b04823657fcfc54225991bc58c93ff0e463b6f12acb28b853",
                    "EndpointID": "83976112bb202b79880777563cd1b06ef27781fd288b210b19fb499e3bf51c90",
                    "Gateway": "172.17.0.1",
                    "IPAddress": "172.17.0.2",
                    "IPPrefixLen": 16,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "02:42:ac:11:00:02",
                    "DriverOpts": null
                }
            }
        }
    }
]

我可以看到IP地址172.17.0.2。再说一遍，我不知道这是从哪里来的。

但现在我可以尝试在我告诉它映射的端口访问容器 IP：

$ curl http://172.17.0.2:8080
curl: (7) Failed to connect to 172.17.0.2 port 8080: Connection refused

出奇，如果我访问相同的容器 IP 但暴露端口 80 它可以工作

sasw@Z3:/$ curl http://172.17.0.2:80
Hello World!

如果我停止并删除完整的容器和图像，然后使用以下随机端口重试：

$ docker run myimage:latest -p 1234:1234
Status: Downloaded newer image for registry.gitlab.com/myimage:latest
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://[::]:80
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
      Content root path: /

似乎这些端口被完全忽略，它仍然监听容器 IP 和端口 80

$ curl http://172.17.0.2:80
Hello World!

很明显，我在这里缺少一些知识，并且我发现的链接不是很有用，也没有向我指出有关 IPv6 的内容，如下所示https://docs.docker.com/config/daemon/ipv6/ https://docs.docker.com/config/daemon/ipv6/其中提到了一些关于/etc/docker/daemon.json我什至没有。

有人能指出正确的方向来了解正在发生的事情及其原因吗？谢谢！

问题似乎是我的论据都没有docker run正在生效，因为我将它们放在图像之后。疯狂的！

So this:

docker run myimage:latest -p 8080:80 --name whatever

将运行容器，完全忽略端口映射和容器分配的名称。

然而这个：

docker run -p 8080:80 --name whatever myimage:latest

将端口 80 映射到我的 localhost:8080，以便 Web 应用程序可以在https://本地主机:8080 https://localhost:8080