第3章 Docker 入门

3.1 确保 Docker 已经就绪
3.2 运行我们的第一个容器
3.3 使用第一个容器
3.4 容器命名
3.5 重新启动已经停止的容器
3.6 附着到容器上
3.7 创建守护式容器
3.8 容器内部都在干些什么
3.9 Docker 日志驱动
3.10 查看容器内的进程
3.11 Docker 统计信息
3.12 在容器内部运行进程
3.13 停止守护式容器
3.14 自动重启容器
3.15 深入容器
3.16 删除容器
3.17 小结

3.1 确保 Docker 已经就绪

$ sudo docker info

3.2 运行我们的第一个容器

$ sudo docker run -i -t ubuntu /bin/bash

-i: 保证容器中 STDIN 是开启的
-t: 为要创建的容器分配一个伪 tty 终端

新创建的容器拥有自己的:

网络
ip
和宿主机通信的桥接网络接口

3.3 使用第一个容器

root@a3fc4d76c6e9:/# hostname
a3fc4d76c6e9

root@a3fc4d76c6e9:/# cat /etc/hosts
127.0.0.1    localhost
::1    localhost ip6-localhost ip6-loopback
fe00::0    ip6-localnet
ff00::0    ip6-mcastprefix
ff02::1    ip6-allnodes
ff02::2    ip6-allrouters
172.17.0.2    a3fc4d76c6e9

我的实验环境中没有 ip 命令.

root@a3fc4d76c6e9:/# ps -aux
USER         PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root           1  0.0  0.0   4232  3468 pts/0    Ss   02:44   0:00 /bin/bash
root          17  0.0  0.0   5880  2776 pts/0    R+   02:58   0:00 ps -aux

root@a3fc4d76c6e9:/# apt-get update && apt-get install vim

root@a3fc4d76c6e9:/# exit
exit
# jdxj @ jdxj-manjaro in ~ [11:00:00] 
$ sudo docker ps -a
[sudo] jdxj 的密码：
CONTAINER ID   IMAGE                       COMMAND                  CREATED          STATUS                      PORTS     NAMES
a3fc4d76c6e9   ubuntu                      "/bin/bash"              16 minutes ago   Exited (0) 53 seconds ago             flamboyant_moser
88132fe6a04b   consul:1.4.4                "docker-entrypoint.s…"   6 days ago       Exited (1) 5 days ago                 consul
351269acdacf   rabbitmq:3.8.9-management   "docker-entrypoint.s…"   2 weeks ago      Exited (0) 2 weeks ago                myrabbit3
1c6772e4177c   rabbitmq:3.8.9-management   "docker-entrypoint.s…"   2 weeks ago      Exited (0) 2 weeks ago                myrabbit2
ce58ec2d0602   rabbitmq:3.8.9-management   "docker-entrypoint.s…"   2 weeks ago      Exited (0) 2 weeks ago                myrabbit1
614ad03e945c   swaggerapi/swagger-editor   "/docker-entrypoint.…"   7 weeks ago      Exited (0) 7 weeks ago                focused_lichterman
9e85bd65e188   mysql:5.7                   "docker-entrypoint.s…"   4 months ago     Exited (0) 2 days ago                 mysql
f483173b2aeb   587380cbba10                "docker-entrypoint.s…"   4 months ago     Exited (0) 2 days ago                 rabbitmq
22d487c89ec6   redis:6                     "docker-entrypoint.s…"   4 months ago     Exited (0) 3 days ago                 redis

3.4 容器命名

$ sudo docker run --name bob_the_container -i -t ubuntu /bin/bash
root@ef61fcc1f09c:/# exit
exit

合法的命名:

3.5 重新启动已经停止的容器

$ sudo docker start bob_the_container
bob_the_container

$ sudo docker start ef61fcc1f09c     
ef61fcc1f09c

$ sudo docker restart ...

$ sudo docker create ...

3.6 附着到容器上

$ sudo docker attach bob_the_container
root@ef61fcc1f09c:/#

$ sudo docker attach ef61fcc1f09c
root@ef61fcc1f09c:/#

3.7 创建守护式容器

交互式容器 (interactive container)
守护式容器 (daemonized container)

$ sudo docker run --name daemon_dave -d ubuntu /bin/sh -c "while true; do echo hello world; sleep 1; done"
5b01d58127a7799b028714e73f0e40bef58afb8fbb1a638f25c4a0d8f9a2c8be

-d

$ sudo docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED              STATUS              PORTS     NAMES
5b01d58127a7   ubuntu    "/bin/sh -c 'while t…"   About a minute ago   Up About a minute             daemon_dave

3.8 容器内部都在干些什么

$ sudo docker logs daemon_dave
hello world
hello world
hello world
...

跟踪 -f :

$ sudo docker logs -f daemon_dave
hello world
hello world
hello world
...
^C

docker logs --tail 10 daemon_dave # 获取最后10行
docker logs --tail 0 -f daemon_dave # 跟踪最新日志而不是整个日志文件

时间戳 -t :

$ sudo docker logs -ft daemon_dave
2021-01-12T03:15:47.131583739Z hello world
2021-01-12T03:15:48.133284530Z hello world
2021-01-12T03:15:49.135542050Z hello world
...
^C

3.9 Docker 日志驱动

—log-driver:

json-file
syslog
none

syslog:

none:

禁用所有容器中的日志
docker logs 命名被禁用

其它日志驱动:

Graylog GELF 协议
Fluentd
日志轮转

3.10 查看容器内的进程

$ sudo docker top daemon_dave
UID                 PID                 PPID                C                   STIME               TTY                 TIME                CMD
root                14807               14787               0                   11:15               ?                   00:00:03            /bin/sh -c while true; do echo hello world; sleep 1; done
root                25954               14807               0                   13:31               ?                   00:00:00            sleep 1

3.11 Docker 统计信息

$ sudo docker stats daemon_dave
CONTAINER ID   NAME          CPU %     MEM USAGE / LIMIT     MEM %     NET I/O       BLOCK I/O    PIDS
5b01d58127a7   daemon_dave   0.20%     2.664MiB / 7.564GiB   0.03%     63.2kB / 0B   348kB / 0B   2
^C

3.12 在容器内部运行进程

启动后台任务:

$ sudo docker exec -d daemon_dave touch /etc/new_config_file

启动交互式任务:

$ sudo docker exec -it daemon_dave /bin/bash

3.13 停止守护式容器

$ sudo docker stop daemon_dave
daemon_dave

docker ps -n x # 显示最后 x 个容器

3.14 自动重启容器

—restart:

always
on-failure

$ sudo docker run --restart=always --name daemon_dave -d ubuntu /bin/sh -c "while true; do echo hello world; sleep 1; done"
e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a

--restart=on-failure:5 # 指定次数

3.15 深入容器

$ sudo docker inspect daemon_dave
[
    {
        "Id": "e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a",
        "Created": "2021-01-12T05:45:58.997841821Z",
        "Path": "/bin/sh",
        "Args": [
            "-c",
            "while true; do echo hello world; sleep 1; done"
        ],
        "State": {
            "Status": "exited",
            "Running": false,
            "Paused": false,
            "Restarting": false,
            "OOMKilled": false,
            "Dead": false,
            "Pid": 0,
            "ExitCode": 137,
            "Error": "",
            "StartedAt": "2021-01-12T05:45:59.378960863Z",
            "FinishedAt": "2021-01-12T05:48:03.603102775Z"
        },
        "Image": "sha256:4e2eef94cd6b93dd4d794c18b45c763f72edc22858e0da5b6e63a4566a54c03c",
        "ResolvConfPath": "/var/lib/docker/containers/e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a/resolv.conf",
        "HostnamePath": "/var/lib/docker/containers/e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a/hostname",
        "HostsPath": "/var/lib/docker/containers/e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a/hosts",
        "LogPath": "/var/lib/docker/containers/e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a/e4be0a1dc144e5993d1d5ca56e8d9f2faf36918b9d37c3f13e3bc8dc48fa9e6a-json.log",
        "Name": "/daemon_dave",
        "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": "always",
                "MaximumRetryCount": 0
            },
            "AutoRemove": false,
            "VolumeDriver": "",
            "VolumesFrom": null,
            "CapAdd": null,
            "CapDrop": null,
            "CgroupnsMode": "host",
            "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/c0a02e5389777c9503b706c4d47610b1fc63305315f1794e28daa5a1ca2c0092-init/diff:/var/lib/docker/overlay2/ac744ee943866cd0be76ee79f366fd892afdc4088ddf37a77453dc3336e9aaf5/diff:/var/lib/docker/overlay2/3d9270cbd9affd9d7802c5ea3064aaf94f65698dfdc9d1e78b265d7ab5886334/diff:/var/lib/docker/overlay2/2e4be4e4aa62ab5dede3ed77261a6a2d9490df614a3fb748f448f38028d27e7e/diff:/var/lib/docker/overlay2/78ac84782a0c925d8e62ae32ab677268ea7055e81844805bee9974a2486b3039/diff",
                "MergedDir": "/var/lib/docker/overlay2/c0a02e5389777c9503b706c4d47610b1fc63305315f1794e28daa5a1ca2c0092/merged",
                "UpperDir": "/var/lib/docker/overlay2/c0a02e5389777c9503b706c4d47610b1fc63305315f1794e28daa5a1ca2c0092/diff",
                "WorkDir": "/var/lib/docker/overlay2/c0a02e5389777c9503b706c4d47610b1fc63305315f1794e28daa5a1ca2c0092/work"
            },
            "Name": "overlay2"
        },
        "Mounts": [],
        "Config": {
            "Hostname": "e4be0a1dc144",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
            ],
            "Cmd": [
                "/bin/sh",
                "-c",
                "while true; do echo hello world; sleep 1; done"
            ],
            "Image": "ubuntu",
            "Volumes": null,
            "WorkingDir": "",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": {}
        },
        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "dfdb27203f768d4614e0b8a1c4b8fc5fda34fb820dc03d01ad1dbddb3631f994",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {},
            "SandboxKey": "/var/run/docker/netns/dfdb27203f76",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "",
            "Gateway": "",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "",
            "IPPrefixLen": 0,
            "IPv6Gateway": "",
            "MacAddress": "",
            "Networks": {
                "bridge": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "f5b93ac2e1eec82ca7f04a1b000ae39dd8c97929301bb544c0ed18baa0f91ffb",
                    "EndpointID": "",
                    "Gateway": "",
                    "IPAddress": "",
                    "IPPrefixLen": 0,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "",
                    "DriverOpts": null
                }
            }
        }
    }
]

格式化选项:

$ sudo docker inspect --format='{{ .State.Running }}' daemon_dave
false

存放容器的目录:

/var/lib/docker/containers

3.16 删除容器

sudo docker rm ...

sudo docker rm -f ... # 删除运行中的容器

删除全部容器:

-q: 只需返回容器 ID

$ sudo docker rm `sudo docker ps -a -q`

3.1 确保 Docker 已经就绪

3.2 运行我们的第一个容器

3.3 使用第一个容器

3.4 容器命名

3.5 重新启动已经停止的容器

3.6 附着到容器上

3.7 创建守护式容器

3.8 容器内部都在干些什么

3.9 Docker 日志驱动

3.10 查看容器内的进程

3.11 Docker 统计信息

3.12 在容器内部运行进程

3.13 停止守护式容器

3.14 自动重启容器

3.15 深入容器

3.16 删除容器

3.17 小结