docker容器映射ip（端口映射与容器互联）

Docker除了通过网络访问外，还提供了两个很方便的功能来满足服务访问的基本需求：

1. 允许映射容器内应用的服务端口到本地宿主主机；

1.从外部访问容器应用

从外部访问容器应用在启动容器的时候，如果不指定对应参数，在容器外部是无法通过网络来访问容器内的网络应用和服务的。当容器中运行一些网络应用，要让外部访问这些应用时，可以通过-P或-p参数来指定端口映射。 当使用-P（大写的）标记时，Docker会随机映射一个49000～49900的端口到内部容器开放的网络端口； 当使用-p（小写的）则可以指定要映射的端口，并且，在一个指定端口上只可以绑定一个容器。支持的格式有IP:HostPort:ContainerPort |IP::ContainerPort | HostPort:ContainerPort

2.映射所有接口地址:

$ docker run -d -p 5000:5000 resource/webapp python test.py 同时也可以映射多个地址： $ docker run -d -p 5000:5000 -p 3000:3000 resource/webapp python test.py

3.映射到指定地址的指定端口:

$ docker run -d -p 127.0.0.1:5000:5000 resource/webapp python test.py

4.映射到指定地址的任意端口:

$ docker run -d -p 127.0.0.1::5000 resource/webapp python test.py

5.查看映射端口配置:

使用docker port命令来查看当前映射的端口配置，同时也可以查看到绑定的地址信息 $ docker port adoring_mendeleev 9000/tcp -> 0.0.0.0:9000 如果想查看容器自己内部的网络和IP地址信息，可以使用docker inspect 容器id:如下： docker inspect 4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140 [ { "Id": "4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140", "Created": "2020-08-13T09:59:13.359463861Z", "Path": "/portainer", "Args": [], "State": { "Status": "running", "Running": true, "Paused": false, "Restarting": false, "OOMKilled": false, "Dead": false, "Pid": 13948, "ExitCode": 0, "Error": "", "StartedAt": "2020-08-30T08:40:01.205520719Z", "FinishedAt": "2020-08-14T03:48:35.028588902Z" }, "Image": "sha256:62771b0b9b0973a3e8e95595534a1240d8cfd968d30ec82dc0393ce0a256c5f3", "ResolvConfPath": "/var/lib/docker/containers/4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140/resolv.conf", "HostnamePath": "/var/lib/docker/containers/4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140/hostname", "HostsPath": "/var/lib/docker/containers/4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140/hosts", "LogPath": "/var/lib/docker/containers/4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140/4a775b0ef021e95c8968dc83d244b77261038e184e351b23f626323bcee37140-json.log", "Name": "/adoring_mendeleev", "RestartCount": 0, "Driver": "overlay2", "Platform": "linux", "MountLabel": "", "ProcessLabel": "", "AppArmorProfile": "", "ExecIDs": null, "HostConfig": { "Binds": [ "/var/run/docker.sock:/var/run/docker.sock", "portainer_data:/data" ], "ContainerIDFile": "", "LogConfig": { "Type": "json-file", "Config": {} }, "NetworkMode": "default", "PortBindings": { "9000/tcp": [ { "HostIp": "", "HostPort": "9000" } ] }, "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/overlay2/4895973fcda8eabffc390b0dfc5a0d22d1d23d7b71256eacfa4dc0c7d662f0cb-init/diff:/var/lib/docker/overlay2/469ee91de1602d2fbfe9e6c56f842a07e31361057c7258d578ef591ec625931a/diff:/var/lib/docker/overlay2/736ee2442a49627b384a170b28053add1894f67b6015760d9e03d66882ab5ea8/diff", "MergedDir": "/var/lib/docker/overlay2/4895973fcda8eabffc390b0dfc5a0d22d1d23d7b71256eacfa4dc0c7d662f0cb/merged", "UpperDir": "/var/lib/docker/overlay2/4895973fcda8eabffc390b0dfc5a0d22d1d23d7b71256eacfa4dc0c7d662f0cb/diff", "WorkDir": "/var/lib/docker/overlay2/4895973fcda8eabffc390b0dfc5a0d22d1d23d7b71256eacfa4dc0c7d662f0cb/work" }, "Name": "overlay2" }, "Mounts": [ { "Type": "volume", "Name": "portainer_data", "Source": "/var/lib/docker/volumes/portainer_data/_data", "Destination": "/data", "Driver": "local", "Mode": "z", "RW": true, "Propagation": "" }, { "Type": "bind", "Source": "/var/run/docker.sock", "Destination": "/var/run/docker.sock", "Mode": "", "RW": true, "Propagation": "rprivate" } ], "Config": { "Hostname": "4a775b0ef021", "Domainname": "", "User": "", "AttachStdin": false, "AttachStdout": false, "AttachStderr": false, "ExposedPorts": { "9000/tcp": {} }, "Tty": false, "OpenStdin": false, "StdinOnce": false, "Env": [ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" ], "Cmd": null, "Image": "portainer/portainer", "Volumes": { "/data": {} }, "WorkingDir": "/", "Entrypoint": [ "/portainer" ], "OnBuild": null, "Labels": {} }, "NetworkSettings": { "Bridge": "", "SandboxID": "136752f95fa8558d98d40336b7c2ad4362f4a554adbdd52045a6b628d148df1b", "HairpinMode": false, "LinkLocalIPv6Address": "", "LinkLocalIPv6PrefixLen": 0, "Ports": { "9000/tcp": [ { "HostIp": "0.0.0.0", "HostPort": "9000" } ] }, "SandboxKey": "/var/run/docker/netns/136752f95fa8", "SecondaryIPAddresses": null, "SecondaryIPv6Addresses": null, "EndpointID": "b45fabb881cb54f5fda7fa1369571ff86e0a63c9c844381e4f2602be468c5679", "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": "d61dbdb3a5311f546b09cbc5e2f5b0448e14d197133e7992d1fa4c9433014396", "EndpointID": "b45fabb881cb54f5fda7fa1369571ff86e0a63c9c844381e4f2602be468c5679", "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 } } } }

1. 2.实现多个容器间通过容器名来快速访问

容器的互联（linking）是一种让多个容器中的应用进行快速交互的方式。它会在源和接收容器之间创建连接关系，接收容器可以通过容器名快速访问到源容器，而不用指定具体的IP地址

1．自定义容器命名

连接系统依据容器的名称来执行。因此，首先需要自定义一个好记的容器命名。虽然当创建容器的时候，系统默认会分配一个名字，但自定义命名容器有两个好处：❑ 自定义的命名，比较好记，比如一个Web应用容器我们可以给它起名叫web，一目了然；❑ 当要连接其他容器时候（即便重启），也可以使用容器名而不用改变，比如连接web容器到db容器。使用--name标记可以为容器自定义命名： $ docker run -d -p 5000:5000 --name web resource/webapp python test.py 容器的名称是唯一的。如果已经命名了一个叫web的容器，当你要再次使用web这个名称的时候，需要先用docker rm命令删除之前创建的同名容器 在执行docker [container] run的时候如果添加--rm标记，则容器在终止后会立刻删除。注意，--rm和-d参数不能同时使用

2．容器互联

使用--link参数可以让容器之间安全地进行交互。

先创建一个新的数据库容器： $ docker run -d --name db test/mysql 创建一个web容器并且连接到db容器： $ docker run -d -p 8888:8888 --name web --link db:db resource/webapp python test.py --link参数的格式为--link name:alias，其中name是要链接的容器的名称，alias是别名 Docker相当于在两个互联的容器之间创建了一个虚机通道，而且不用映射它们的端口到宿主主机上。在启动db容器的时候并没有使用-p和-P标记，从而避免了暴露数据库服务端口到外部网络上。 Docker通过两种方式为容器公开连接信息： ❑ 更新环境变量； ❑ 更新/etc/hosts文件。 使用env命令来查看web容器的环境变量：