Docker命令行介绍
docker + 管理的对象(比如容器,镜像) + 具体操作(比如创建,启动,停止,删除)
示例:
docker image pull nginx
拉取一个叫nginx的docker image镜像。docker container stop web
停止一个叫web的docker container容器。
镜像 vs 容器
image镜像
- Docker image是一个
read-only
文件。 - 这个文件包含文件系统,源码,库文件,依赖,工具等一些运行application所需要的文件。
- 可以理解成一个模板。
- Docker image具有分层的概念。
container容器
- 一个运行中的Docker image。
- 实质是复制image并在image最上层加上一层
read-write
的层 (称之为container layer
, 容器层)。 - 基于同一个image可以创建多个container。
Docker image的获取
- 自己制作(借助Dockerfile,参考 4. Dockerfile完全指南)
- 从registry拉取(比如Docker Hub)
容器的基本操作
常用命令
操作 | 命令(全) | 命令(简) |
---|---|---|
容器的创建 | docker container run <image name> | docker run <image name> |
容器的列出(up) | docker container ls | docker ps |
容器的列出(up和exit) | docker container ls -a | docker ps -a |
容器的停止 | docker container stop <name or ID> | docker stop <container name or ID> |
容器的删除 | docker container rm <name or ID> | docker rm <container name or ID> |
示例:
$ docker container run nginx $ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 343fd4031609 nginx "/docker-entrypoint.…" 6 seconds ago Up 5 seconds 80/tcp xenodochial_clarke $ docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 343fd4031609 nginx "/docker-entrypoint.…" 14 seconds ago Up 13 seconds 80/tcp xenodochial_clarke $ docker container stop 34 34 $ docker container ls -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 343fd4031609 nginx "/docker-entrypoint.…" 29 seconds ago Exited (0) 5 seconds ago xenodochial_clarke d9095daa8bcf nginx "/docker-entrypoint.…" 28 minutes ago Exited (0) 28 minutes ago suspicious_shamir $ docker container rm 34 34 $ docker container ls -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES d9095daa8bcf nginx "/docker-entrypoint.…" 28 minutes ago Exited (0) 28 minutes ago suspicious_shamir $
命令小技巧
批量停止
$ docker container ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES cd3a825fedeb nginx "/docker-entrypoint.…" 7 seconds ago Up 6 seconds 80/tcp mystifying_leakey 269494fe89fa nginx "/docker-entrypoint.…" 9 seconds ago Up 8 seconds 80/tcp funny_gauss 34b68af9deef nginx "/docker-entrypoint.…" 12 seconds ago Up 10 seconds 80/tcp interesting_mahavira 7513949674fc nginx "/docker-entrypoint.…" 13 seconds ago Up 12 seconds 80/tcp kind_nobel
方法1
$ docker container rm cd3 269 34b 751
方法2
$ docker container stop $(docker container ps -q) cd3a825fedeb 269494fe89fa 34b68af9deef 7513949674fc $ docker container ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES cd3a825fedeb nginx "/docker-entrypoint.…" 30 seconds ago Exited (0) 2 seconds ago mystifying_leakey 269494fe89fa nginx "/docker-entrypoint.…" 32 seconds ago Exited (0) 2 seconds ago funny_gauss 34b68af9deef nginx "/docker-entrypoint.…" 35 seconds ago Exited (0) 2 seconds ago interesting_mahavira 7513949674fc nginx "/docker-entrypoint.…" 36 seconds ago Exited (0) 2 seconds ago kind_nobel $
也可以使用docker container ps -q | xargs docker container stop
,和上面的操作本质是等效的。
批量删除
和批量停止类似,可以使用 docker container rm $(docker container ps -aq)
。
docker system prune -a -f
可以快速对系统进行清理,删除停止的容器,不用的image,等等。
docker命令帮助文档
首先是docker --help
,用于查看全部的帮忙选项,输出如下:
~# docker --help Usage: docker [OPTIONS] COMMAND A self-sufficient runtime for containers Options: --config string Location of client config files (default "/root/.docker") -c, --context string Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with "docker context use") -D, --debug Enable debug mode -H, --host list Daemon socket(s) to connect to -l, --log-level string Set the logging level ("debug"|"info"|"warn"|"error"|"fatal") (default "info") --tls Use TLS; implied by --tlsverify --tlscacert string Trust certs signed only by this CA (default "/root/.docker/ca.pem") --tlscert string Path to TLS certificate file (default "/root/.docker/cert.pem") --tlskey string Path to TLS key file (default "/root/.docker/key.pem") --tlsverify Use TLS and verify the remote -v, --version Print version information and quit Management Commands: builder Manage builds buildx* Docker Buildx (Docker Inc., v0.8.2) compose* Docker Compose (Docker Inc., v2.4.1) config Manage Docker configs container Manage containers context Manage contexts image Manage images manifest Manage Docker image manifests and manifest lists network Manage networks node Manage Swarm nodes plugin Manage plugins sbom* View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc., 0.6.0) scan* Docker Scan (Docker Inc., v0.17.0) secret Manage Docker secrets service Manage services stack Manage Docker stacks swarm Manage Swarm system Manage Docker trust Manage trust on Docker images volume Manage volumes Commands: attach Attach local standard input, output, and error streams to a running container build Build an image from a Dockerfile commit Create a new image from a container's changes cp Copy files/folders between a container and the local filesystem create Create a new container diff Inspect changes to files or directories on a container's filesystem events Get real time events from the server exec Run a command in a running container export Export a container's filesystem as a tar archive history Show the history of an image images List images import Import the contents from a tarball to create a filesystem image info Display system-wide information inspect Return low-level information on Docker objects kill Kill one or more running containers load Load an image from a tar archive or STDIN login Log in to a Docker registry logout Log out from a Docker registry logs Fetch the logs of a container pause Pause all processes within one or more containers port List port mappings or a specific mapping for the container ps List containers pull Pull an image or a repository from a registry push Push an image or a repository to a registry rename Rename a container restart Restart one or more containers rm Remove one or more containers rmi Remove one or more images run Run a command in a new container save Save one or more images to a tar archive (streamed to STDOUT by default) search Search the Docker Hub for images start Start one or more stopped containers stats Display a live stream of container(s) resource usage statistics stop Stop one or more running containers tag Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE top Display the running processes of a container unpause Unpause all processes within one or more containers update Update configuration of one or more containers version Show the Docker version information wait Block until one or more containers stop, then print their exit codes Run 'docker COMMAND --help' for more information on a command. To get more help with docker, check out our guides at https://docs.docker.com/go/guides/
接下来是针对某个命令的帮助文档,比如查看容器命令相关的文档,可以使用docker container --help
,如下:
~# docker container --help Usage: docker container COMMAND Manage containers Commands: attach Attach local standard input, output, and error streams to a running container commit Create a new image from a container's changes cp Copy files/folders between a container and the local filesystem create Create a new container diff Inspect changes to files or directories on a container's filesystem exec Run a command in a running container export Export a container's filesystem as a tar archive inspect Display detailed information on one or more containers kill Kill one or more running containers logs Fetch the logs of a container ls List containers pause Pause all processes within one or more containers port List port mappings or a specific mapping for the container prune Remove all stopped containers rename Rename a container restart Restart one or more containers rm Remove one or more containers run Run a command in a new container start Start one or more stopped containers stats Display a live stream of container(s) resource usage statistics stop Stop one or more running containers top Display the running processes of a container unpause Unpause all processes within one or more containers update Update configuration of one or more containers wait Block until one or more containers stop, then print their exit codes Run 'docker container COMMAND --help' for more information on a command.
还可以继续查看下一级命令的帮助文档,比如使用docker container run --help
查看运行容器的相关选项,如下:
~# docker container run --help Usage: docker container run [OPTIONS] IMAGE [COMMAND] [ARG...] Run a command in a new container Options: --add-host list Add a custom host-to-IP mapping (host:ip) -a, --attach list Attach to STDIN, STDOUT or STDERR --blkio-weight uint16 Block IO (relative weight), between 10 and 1000, or 0 to disable (default 0) --blkio-weight-device list Block IO weight (relative device weight) (default []) --cap-add list Add Linux capabilities --cap-drop list Drop Linux capabilities --cgroup-parent string Optional parent cgroup for the container --cgroupns string Cgroup namespace to use (host|private) 'host': Run the container in the Docker host's cgroup namespace 'private': Run the container in its own private cgroup namespace '': Use the cgroup namespace as configured by the default-cgroupns-mode option on the daemon (default) --cidfile string Write the container ID to the file --cpu-period int Limit CPU CFS (Completely Fair Scheduler) period --cpu-quota int Limit CPU CFS (Completely Fair Scheduler) quota --cpu-rt-period int Limit CPU real-time period in microseconds --cpu-rt-runtime int Limit CPU real-time runtime in microseconds -c, --cpu-shares int CPU shares (relative weight) --cpus decimal Number of CPUs --cpuset-cpus string CPUs in which to allow execution (0-3, 0,1) --cpuset-mems string MEMs in which to allow execution (0-3, 0,1) -d, --detach Run container in background and print container ID --detach-keys string Override the key sequence for detaching a container --device list Add a host device to the container --device-cgroup-rule list Add a rule to the cgroup allowed devices list --device-read-bps list Limit read rate (bytes per second) from a device (default []) --device-read-iops list Limit read rate (IO per second) from a device (default []) --device-write-bps list Limit write rate (bytes per second) to a device (default []) --device-write-iops list Limit write rate (IO per second) to a device (default []) --disable-content-trust Skip image verification (default true) --dns list Set custom DNS servers --dns-option list Set DNS options --dns-search list Set custom DNS search domains --domainname string Container NIS domain name --entrypoint string Overwrite the default ENTRYPOINT of the image -e, --env list Set environment variables --env-file list Read in a file of environment variables --expose list Expose a port or a range of ports --gpus gpu-request GPU devices to add to the container ('all' to pass all GPUs) --group-add list Add additional groups to join --health-cmd string Command to run to check health --health-interval duration Time between running the check (ms|s|m|h) (default 0s) --health-retries int Consecutive failures needed to report unhealthy --health-start-period duration Start period for the container to initialize before starting health-retries countdown (ms|s|m|h) (default 0s) --health-timeout duration Maximum time to allow one check to run (ms|s|m|h) (default 0s) --help Print usage -h, --hostname string Container host name --init Run an init inside the container that forwards signals and reaps processes -i, --interactive Keep STDIN open even if not attached --ip string IPv4 address (e.g., 172.30.100.104) --ip6 string IPv6 address (e.g., 2001:db8::33) --ipc string IPC mode to use --isolation string Container isolation technology --kernel-memory bytes Kernel memory limit -l, --label list Set meta data on a container --label-file list Read in a line delimited file of labels --link list Add link to another container --link-local-ip list Container IPv4/IPv6 link-local addresses --log-driver string Logging driver for the container --log-opt list Log driver options --mac-address string Container MAC address (e.g., 92:d0:c6:0a:29:33) -m, --memory bytes Memory limit --memory-reservation bytes Memory soft limit --memory-swap bytes Swap limit equal to memory plus swap: '-1' to enable unlimited swap --memory-swappiness int Tune container memory swappiness (0 to 100) (default -1) --mount mount Attach a filesystem mount to the container --name string Assign a name to the container --network network Connect a container to a network --network-alias list Add network-scoped alias for the container --no-healthcheck Disable any container-specified HEALTHCHECK --oom-kill-disable Disable OOM Killer --oom-score-adj int Tune host's OOM preferences (-1000 to 1000) --pid string PID namespace to use --pids-limit int Tune container pids limit (set -1 for unlimited) --platform string Set platform if server is multi-platform capable --privileged Give extended privileges to this container -p, --publish list Publish a container's port(s) to the host -P, --publish-all Publish all exposed ports to random ports --pull string Pull image before running ("always"|"missing"|"never") (default "missing") --read-only Mount the container's root filesystem as read only --restart string Restart policy to apply when a container exits (default "no") --rm Automatically remove the container when it exits --runtime string Runtime to use for this container --security-opt list Security Options --shm-size bytes Size of /dev/shm --sig-proxy Proxy received signals to the process (default true) --stop-signal string Signal to stop a container (default "SIGTERM") --stop-timeout int Timeout (in seconds) to stop a container --storage-opt list Storage driver options for the container --sysctl map Sysctl options (default map[]) --tmpfs list Mount a tmpfs directory -t, --tty Allocate a pseudo-TTY --ulimit ulimit Ulimit options (default []) -u, --user string Username or UID (format: <name|uid>[:<group|gid>]) --userns string User namespace to use --uts string UTS namespace to use -v, --volume list Bind mount a volume --volume-driver string Optional volume driver for the container --volumes-from list Mount volumes from the specified container(s) -w, --workdir string Working directory inside the container
容器运行模式
//TODO attach模式和detach模式。
连接容器的 shell
docker container run -it
创建一个容器并进入交互式模式。
➜ ~ docker container run -it busybox sh / # / # / # ls bin dev etc home proc root sys tmp usr var / # ps PID USER TIME COMMAND 1 root 0:00 sh 8 root 0:00 ps / # exit
docker container exec -it
在一个已经运行的容器里执行一个额外的command。
➜ ~ docker container run -d nginx 33d2ee50cfc46b5ee0b290f6ad75d724551be50217f691e68d15722328f11ef6 ➜ ~ ➜ ~ docker container exec -it 33d sh # # # ls bin boot dev docker-entrypoint.d docker-entrypoint.sh etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var # # exit ➜ ~
容器 vs 虚拟机
容器不是Mini虚拟机
- 容器其实是进程(Containers are just processes)。
- 容器中的进程被限制了对CPU内存等资源的访问。
- 当进程停止后,容器就退出了。
容器的进程process
以下是在Ubuntu20.04中演示,因Windows环境下的Docker和Linux具有一些差异。pstree
命令需要额外安装,可以使用 yum install psmisc
或者 sudo apt-get install psmisc
安装
➜ ~ docker container run -d nginx 57fe4033dd7e1e620a0b6a7b83b85d4f8f98772f0ce585624c384de254826fd0 ➜ ~ docker container ls CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 57fe4033dd7e nginx "/docker-entrypoint.…" 4 seconds ago Up 3 seconds 80/tcp festive_proskuriakova ➜ ~ docker container top 57f UID PID PPID C STIME TTY TIME CMD root 7646 7625 0 12:14 ? 00:00:00 nginx: master process nginx -g daemon off; systemd+ 7718 7646 0 12:14 ? 00:00:00 nginx: worker process ➜ ~ ➜ ~ ➜ ~ ps -aef --forest UID PID PPID C STIME TTY TIME CMD root 1 0 0 May14 ? 00:00:00 /init root 157 1 0 May14 ? 00:00:00 /init root 523 157 0 May14 ? 00:02:32 \_ /usr/bin/dockerd -p /var/run/docker.pid root 545 523 0 May14 ? 00:25:55 | \_ containerd --config /var/run/docker/containerd/containerd.toml --log-level info root 7625 157 0 12:14 ? 00:00:00 \_ /usr/bin/containerd-shim-runc-v2 -namespace moby -id 57fe4033dd7e1e620a0b6a7b83b85d4f8f98772f0ce585624c384de254826fd0 -address /var/run/d root 7646 7625 0 12:14 ? 00:00:00 \_ nginx: master process nginx -g daemon off; systemd+ 7718 7646 0 12:14 ? 00:00:00 \_ nginx: worker process root 6442 1 0 May18 ? 00:00:00 /init root 6443 6442 0 May18 ? 00:00:00 \_ /init penxiao 6444 6443 0 May18 pts/2 00:00:01 \_ -zsh penxiao 7770 6444 0 12:15 pts/2 00:00:00 \_ ps -aef --forest ➜ ~ ➜ ~ pstree -halps 7718 init,1 └─init,157 └─containerd-shim,7625 -namespace moby -id 57fe4033dd7e1e620a0b6a7b83b85d4f8f98772f0ce585624c384de254826fd0 -address /var/run/docker/containerd/containerd.sock └─nginx,7646 └─nginx,7718
Gain Access to the MobyLinux VM on Windows or MacOS
https://nickjanetakis.com/blog/docker-tip-70-gain-access-to-the-mobylinux-vm-on-windows-or-macos
docker container run 背后发生了什么?
$ docker container run -d --publish 80:80 --name webhost nginx
- 在本地查找是否有nginx这个image镜像,但是没有发现
- 去远程的image registry查找nginx镜像(默认的registry是Docker Hub)
- 下载最新版本的nginx镜像 (nginx:latest 默认)
- 基于nginx镜像来创建一个新的容器,并且准备运行
- docker engine分配给这个容器一个虚拟IP地址
- 在宿主机上打开80端口并把容器的80端口转发到宿主机上
- 启动容器,运行指定的命令(这里是一个shell脚本去启动nginx)
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