[Docker]二.Docker 镜像,仓库,容器介绍以及详解

一.Docker 镜像,容器,仓库的简单介绍

通俗来讲:镜像相当于VM虚拟机中的ios文件,容器相当于虚拟机系统,仓库相当于系统中的进程或者执行文件,容器是通过镜像创建的

 1.镜像

Docker 镜像就是一个 Linux 的文件系统（ Root FileSystem ），这个文件系统里面包含可以运行在 Linux 内核的程序以及相应的数据,这里要强调一下镜像的两个特征:

镜像是分层（Layer）的

        即一个镜像可以多个中间层组成，多个镜像可以共享同一中间层，也可以通过在镜像添加多一层来生成一个新的镜像

镜像是只读的（read-only）

         镜像在构建完成之后，便不可以再修改，而上面所说的添加一层构建新的镜像，这中间实际是通过创建一个临时的容器，在容器上增加或删除文件，从而形成新的镜像，因为容器是可以动态改变的

 2.容器

        类似 linux 系统环境， 运行和隔离应用 ,容器从镜像启动的时候， docker 会在镜像的最上一层创建一个可写层， 镜像本身是只读的 ，保持不变,容器与镜像的关系，就如同面向编程中

对象与类之间的关系。

        因为 容器是通过镜像来创建的 ，所以必须先有镜像才能创建容器，而生成的容器是一个独立于宿主机的隔离进程，并且有属于容器自己的网络和命名空间。

        前面介绍过，镜像由多个中间层（layer ）组成，生成的镜像是只读的，但容器却是可读

可写的，这是因为容器是在镜像上面添一层读写层（ writer/read layer ）来实现的，如下图所

示：

3.仓库（Repository） 

仓库（Repository）是集中存储镜像的地方 ，这里有个概念要区分一下，那就是 仓库 与 仓库

服务器 (Registry) 是两回事，像上面说的 Docker Hub ，就是 Docker 官方提供的一个仓库服务器，不过其实有时候不太需要太过区分这两个概念

公共仓库

公共仓库一般是指 Docker Hub ，前面已经多次介绍如何从 Docker Hub 获取镜像，除了获取镜像外，也可以将自己构建的镜像存放到 Docker Hub ，这样，别人也可以使用我们构建的镜像,不过要将镜像上传到 Docker Hub ，必须先在 Docker 的官方网站上注册一个账号，注册界面如下，按要求填写必要的信息就可以注册了

 私有仓库

有时候自己部门内部有一些镜像要共享时，如果直接导出镜像拿给别人又比较麻烦，使用像

Docker Hub 这样的公共仓库又不是很方便，这时候可以自己搭建属于自己的私有仓库服务，用于存储和分布自己的镜像

二.Docker 镜像以及仓库 

Docker 镜像就是一个 Linux 的文件系统（ Root FileSystem ），这个文件系统里面包含可以运行在 Linux 内核的程序以及相应的数据

1.docker search 搜索镜像

docker search centos

[root@localhost containerd]# docker search --help

Usage:  docker search [OPTIONS] TERM

Search the Docker Hub for images

Options:
  -f, --filter filter   Filter output based on conditions provided
      --format string   Pretty-print search using a Go template
      --limit int       Max number of search results (default 25)
      --no-trunc        Don't truncate output

备注： -f STARS=3000 搜索 STARS 大于 3000 的镜像

搜索mysql  STARS 大于 3000的镜像 

[root@localhost containerd]# docker search mysql -f STARS=3000
NAME      DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
mysql     MySQL is a widely used, open-source relation…   14530     [OK]       
mariadb   MariaDB Server is a high performing open sou…   5550      [OK]  

2.docker pull 下载镜像

下载docker pull centos最新的镜像

docker pull centos

[root@localhost /]# docker pull centos
Using default tag: latest
latest: Pulling from library/centos
7a0437f04f83: Pull complete
Digest: sha256:5528e8b1b1719d34604c87e11dcd1c0a20bedf46e83b5632cdeac91b8c04efc1
Status: Downloaded newer image for centos:latest
docker.io/library/centos:latest

下载指定的tag的镜像:docker pull centos:8.3.2011

[root@localhost /]# docker pull centos:8.3.2011
8.3.2011: Pulling from library/centos
Digest: sha256:5528e8b1b1719d34604c87e11dcd1c0a20bedf46e83b5632cdeac91b8c04efc1
Status: Downloaded newer image for centos:8.3.2011
docker.io/library/centos:8.3.2011

下载nginx镜像: nginx镜像中集成了一个linux操作系统,在操作系统中又集成了nginx,然后打包成一个nginx镜像,下载好nginx镜像后,然后启动该服务,就可以进行web服务操作了,实际上在下载nignx镜像的时候,其实不是一下子就下载好了的,而是一层一层地下载其他镜像,然后打包成nginx镜像

root@localhost zph]# docker pull nginx
Using default tag: latest
latest: Pulling from library/nginx
Digest: sha256:b4af4f8b6470febf45dc10f564551af682a802eda1743055a7dfc8332dffa595
Status: Downloaded newer image for nginx:latest
docker.io/library/nginx:latest

3.镜像结构

镜像结构:docker.io/library/centos:latest

[root@localhost containerd]# docker pull centos
Using default tag: latest
latest: Pulling from library/centos
Digest: sha256:a27fd8080b517143cbbbab9dfb7c8571c40d67d534bbdee55bd6c473f432b177
Status: Downloaded newer image for centos:latest
docker.io/library/centos:latest

4.docker images 查看本地镜像

[root@localhost containerd]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
nginx              latest              bc649bab30d1   10 days ago     187MB
hello-world        latest              9c7a54a9a43c   5 months ago    13.3kB
centos             latest              5d0da3dc9764   2 years ago     231MB

5.docker tag 给镜像打标签

比如:下载了一个镜像,启动了这个容器,在这个容器中做了一些操作,然后就想把这个容器制作成自己的镜像,那么就需要给这个镜像打标签(相当于发布这个镜像,制作好这个镜像后,就可以把它发布到远程仓库了),给镜像打标签可以创建自己的镜像, 自定义镜像结构命名规则如下 : registry name/repository name/image name:tag name ,例如:docker.io/library/centos:latest

[root@localhost zph]# docker tag --help

Usage:  docker tag SOURCE_IMAGE[:TAG] TARGET_IMAGE[:TAG]

Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE

 对上述说明:

        SOURCE_IMAGE 镜像名   [:TAG] 镜像标签名

        TARGET_IMAGE 打包新的镜像名 [:TAG] 新镜像标签名

比如:把nginx镜像打包成一个新的镜像:

docker tag nginx  docker.io/zph/nginx:last 或者把nginx替换成对应的IMAGE ID,如: 

docker tag bc649bab30d1 docker.io/zph/nginx:v2

root@localhost zph]# docker tag nginx  docker.io/zph/nginx:last
[root@localhost zph]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
nginx              latest              bc649bab30d1   10 days ago     187MB
zph/nginx          last                bc649bab30d1   10 days ago     187MB

6.把本地镜像推送到 dockerHub 仓库 

(1).需要在dockerHub上面注册一个账户

把打包好的镜像发布到远程(hub.docker.com官网)自己的账号下,需要有一个docker账号

(2).使用 docker login 本地登录 dockerHub 

[root@localhost ~]# docker login
Login with your Docker ID to push and pull images from Docker Hub. If you don't have
a Docker ID, head over to https://hub.docker.com to create one. 
Username: zph
Password:
WARNING! Your password will be stored unencrypted in /root/.docker/config.json. Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store
Login Succeeded

登录成功后,会把账号信息保存到.docker/config.json中,查看保存的账户信息

[root@localhost ~]# cat .docker/config.json
{ 
"auths": { 
    "https://index.docker.io/v1/": 
        { 
        "auth": "aXR5aW5nOxxxzEyMzQ="
        }
    }
}

(3).docker push 镜像名称 把本地镜像推送到远程

下载一个alpine的镜像演示，alpine是一个比较小的的 linux 镜像

[root@localhost ~]# 下载alpine镜像
[root@localhost ~]# docker pull alpine
[root@localhost ~]# 打包alpine镜像
[root@localhost ~]# docker tag d4ff818577bc docker.io/itying/alpine:v1.0.1
[root@localhost ~]# docker tag d4ff818577bc docker.io/itying/alpine:latest
[root@localhost ~]# 查看alpine镜像
[root@localhost ~]# docker images | grep alpine
itying/alpine v1.0.1 d4ff818577bc 4 weeks ago 5.6MB
alpine 3.14.0 d4ff818577bc 4 weeks ago 5.6MB
alpine latest d4ff818577bc 4 weeks ago 5.6MB
[root@localhost ~]# 发布apline镜像到dockerHub
[root@localhost ~]# docker push docker.io/itying/alpine:v1.0.1
The push refers to repository [docker.io/itying/alpine]
72e830a4dff5: Mounted from library/alpine
v1.0.1: digest: sha256:1775bebec23e1f3ce4869xxx26497d82f2ffca9
d size: 528

7.docker rmi 删除镜像 

查看本地镜像

[root@localhost zph]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
nginx              latest              bc649bab30d1   10 days ago     187MB
zph/nginx          last                bc649bab30d1   10 days ago     187MB
zph/nginx          v2                  bc649bab30d1   10 days ago     187MB
hello-world        latest              9c7a54a9a43c   5 months ago    13.3kB
centos             latest              5d0da3dc9764   2 years ago     231MB

 删除对应的标签镜像:docker rmi 镜像名:版本,如下:

[root@localhost zph]# docker rmi zph/nginx:v2
Untagged: zph/nginx:v2
[root@localhost zph]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
nginx              latest              bc649bab30d1   10 days ago     187MB
zph/nginx          last                bc649bab30d1   10 days ago     187MB
hello-world        latest              9c7a54a9a43c   5 months ago    13.3kB
centos             latest              5d0da3dc9764   2 years ago     231MB

如果要删除IMAGE ID的镜像,则使用命令:docker rmi -f IMAGE ID, 如:

[root@localhost zph]# docker rmi -f bc649bab30d1
Untagged: nginx:latest
Untagged: nginx@sha256:b4af4f8b6470febf45dc10f564551af682a802eda1743055a7dfc8332dffa595
Untagged: zph/nginx:last
Deleted: sha256:bc649bab30d150c10a84031a7f54c99a8c31069c7bc324a7899d7125d59cc973
Deleted: sha256:c6f480996a203ed077606cce624f944b041449833e2db3f7d19fe22974fb965b
Deleted: sha256:e4347a01432c5f4350b041632f5703c3dd47de2ec68547b9339d11ea44708389
Deleted: sha256:9d40098fc19fdfff9c74fd3c2c0ff49bfda7d9d04b5d7806d0843d32055d769a
Deleted: sha256:165ae0ef2ddd33b6d5a7f206633b9b0c30cd94ff18a4ed5c3aeb59bf28388526
Deleted: sha256:06dabb44ac4d1f0b5544255e944f15a939178d77aff60a5b296e38bd8743efeb
Deleted: sha256:ee220599571f649e0fb74b40db1615a4c9c1355ac912f9e70087b695617af352
Deleted: sha256:cb4596cc145400fb1f2aa56d41516b39a366ecdee7bf3f9191116444aacd8c90

[root@localhost zph]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
hello-world        latest              9c7a54a9a43c   5 months ago    13.3kB
centos             latest              5d0da3dc9764   2 years ago     231MB

这样就会删除IMAGE ID 为 bc649bab30d1的nginx 镜像了

三.Docker 容器

类似 linux 系统环境，运行和隔离应用, 容器从镜像启动的 时候， docker 会在 镜像的最上一

层 创建一个 可写层 ，镜像本身是 只读的 ，保持不变,容器与镜像的关系，就如同面向编程中对象与类之间的关系。

因为容器是通过镜像来创建的，所以必须先有镜像才能创建容器，而生成的容器是一个独立

于宿主机的隔离进程，并且有属于容器自己的网络和命名空间

1.查看所的容器 

查看所有运行的容器

[root@localhost zph]# docker ps
CONTAINER ID   IMAGE                        COMMAND                  CREATED         STATUS       PORTS                                                                                                                                                                                                     NAMES
757e72f3b32e   rabbitmq:3.7.16-management   "docker-entrypoint.s…"   22 months ago   Up 6 hours   0.0.0.0:4369->4369/tcp, :::4369->4369/tcp, 5671/tcp, 0.0.0.0:5672->5672/tcp, :::5672->5672/tcp, 0.0.0.0:15672->15672/tcp, :::15672->15672/tcp, 0.0.0.0:25672->25672/tcp, :::25672->25672/tcp, 15671/tcp   dockerlnmp_rabbitmq_1
e526c3df36f7   dockerlnmp_mysql             "docker-entrypoint.s…"   22 months ago   Up 6 hours   0.0.0.0:3306->3306/tcp, :::3306->3306/tcp, 33060/tcp                                                 

 查看所有容器(既有运行中的容器,也有被销毁的容器)

[root@localhost zph]# docker ps -a
CONTAINER ID   IMAGE                        COMMAND                  CREATED         STATUS                       PORTS                                                                                                                                                                                                     NAMES
8def313c4f6e   hello-world                  "/hello"                 5 hours ago     Exited (0) 5 hours ago                                                                                                                                                                                                                 intelligent_johnson
59222227ec81   dockerlnmp_nginx             "/usr/bin/supervisor…"   21 months ago   Exited (0) 19 months ago                                                                                                                                                                                                               dockerlnmp_nginx_1
ed99ccb1576f   dockerlnmp_php               "/usr/bin/supervisor…"   21 months ago   Exited (0) 19 months ago                                                                                                                                                                                                               dockerlnmp_php_1
9299363ef447   composer:latest              "/docker-entrypoint.…"   21 months ago   Exited (1) 19 months ago                                                                                                                                                                                                               composer
b4791a6baf69   c6f915833fb6                 "/bin/sh -c 'mkdir -…"   21 months ago   Exited (1) 21 months ago                                                                                                             

2.docker run 参数

[root@localhost zph]# docker run --help

Usage:  docker 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: [:])
      --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

常用命令如下:

docker run:

        创建一个新的容器并运行一个命令

        docker run 是日常用的最频繁用的命令之一，同样也是较为复杂的命令之一

命令格式：

         docker run [OPTIONS] IMAGE [COMMAND] [ARG...]

OPTIONS :选项

        -i :表示启动一个可交互的容器，并持续打开标准输入

        -t: 表示使用终端关联到容器的标准输入输出上

        -d :表示容器放置后台运行

        --rm:退出后即删除容器

        --name :表示定义容器唯一名称

        -p 映射端口

        -v 指定路径挂载数据卷

        -e 运行容器传递环境变量

IMAGE :

        表示要运行的镜像

COMMAND :

        表示启动容器时要运行的命令

3.-it 启动一个交互式容器

docker run 启动一个交互式容器在容器内执行/bin/bash 命令:

docker run -it --name centos7 centos /bin/bash 或者 docker run -it  --name centos7 5d0da3dc9764  /bin/bash 

5d0da3dc9764   为centos镜像的IMAGE ID, --name 给这个容器命名

[root@localhost zph]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
hello-world        latest              9c7a54a9a43c   5 months ago    13.3kB
centos             latest              5d0da3dc9764   2 years ago     231MB
[root@localhost zph]# docker run -it --name centos7 9c7a54a9a43c    /bin/bash
[root@8780efa9cf48 /]# ls
bin  dev  etc  home  lib  lib64  lost+found  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var

可以在容器中执行操作命令,如:ls cat,还可以在容器中安装一些软件,相当于把容器当作一个操作系统,只不过这个操作系统是一个比较精简的操作系统而已 

[root@0f0b83575aa4 /]# 进入容器后查看容器的IP地址
[root@0f0b83575aa4 /]# ifconfig
bash: ifconfig: command not found

#s说明没有这个命令,使用yum安装命令操作
[root@0f0b83575aa4 /]# yum install net-tools
Loaded plugins: fastestmirror, ovl
Determining fastest mirrors
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com

...

#安装成功后,使用ifconfig查看就可以了
[root@0f0b83575aa4 /]# ifconfig
eth0: flags=4163  mtu 1500
        inet 172.17.0.2  netmask 255.255.0.0  broadcast 172.17.255.255
        ether 02:42:ac:11:00:02  txqueuelen 0  (Ethernet)
        RX packets 17779  bytes 32924504 (31.3 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 8464  bytes 495661 (484.0 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        loop  txqueuelen 1000  (Local Loopback)
        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

 退出容器

        exit: 容器停止并退出

        ctrl+p+q：容器不停止退出

4.--rm 启动一个退出即删除容器 

创建一个非交互式的容器用完就删除,也就是退出容器后就销毁

docker run --rm centos7 /bin/bash

创建一个交互式的容器用完就删

docker run -it --rm centos7 /bin/bash

exit 退出后,执行命令docker ps -a,发现上面的centos7已经被销毁了,没有这个记录

5.-d 启动一个后台容器

开启一个后台交互的容器，注意启动的时候加上-it,如果不加的话 docker 启动容器会自动停

止,也就是说,加上-d后,就是启动这个容器,然后在后台运行,不进入这个容器,eg:

# 启动一个centos容器,并命名,执行/bin/bash,在后台运行,不进入容器内部
[root@localhost zph]# docker run -it --name centos7-bak -d eeb6ee3f44bd /bin/bash
# 该命令执行后,出现下面字符串
48830cb9e3177724a977a0ba1d6f0a1d06ceca016a148a7e9358bab9da3fe652
[root@localhost zph]# 
#查看容器:发现存在cents7-bak这个容器,说明了上面docker run 命令的正确性
[root@localhost zph]# docker ps
CONTAINER ID   IMAGE                        COMMAND                  CREATED          STATUS          PORTS                                                                                                                                                                                                     NAMES
48830cb9e317   eeb6ee3f44bd                 "/bin/bash"              15 seconds ago   Up 13 seconds                                                                                                                                                                                                             centos7-bak

 6.exec 进入置为后台已经启动的容器

进入一个容器可以使用 docker exec 或者 docker attac,用得最多的是docker exec这个命令,文档如下:    

[root@localhost zph]# docker exec --help

Usage:  docker exec [OPTIONS] CONTAINER COMMAND [ARG...]

Run a command in a running container

Options:
  -d, --detach               Detached mode: run command in the background
      --detach-keys string   Override the key sequence for detaching a container
  -e, --env list             Set environment variables
      --env-file list        Read in a file of environment variables
  -i, --interactive          Keep STDIN open even if not attached
      --privileged           Give extended privileges to the command
  -t, --tty                  Allocate a pseudo-TTY
  -u, --user string          Username or UID (format: [:])
  -w, --workdir string       Working directory inside the container

 docker attach文档:

[root@localhost zph]# docker attach --help

Usage:  docker attach [OPTIONS] CONTAINER

Attach local standard input, output, and error streams to a running container

Options:
      --detach-keys string   Override the key sequence for detaching a container
      --no-stdin             Do not attach STDIN
      --sig-proxy            Proxy all received signals to the process (default true)

 两个命令的区别：

        docker exec： 进入容器开启一个新的终端（常用） 执行 exit 退出的时候不会停止容器,使用docker ps 查看时,容器存在,不会被销毁

        docker attach： 进入容器正在执行的终端 exit 退出会停止容器,docker ps查看时,容器不存在,已经被销毁了

#查看正在运行的容器
[]root@localhost zph]# docker ps
CONTAINER ID   IMAGE                        COMMAND                  CREATED          STATUS          PORTS                                                                                                                                                                                                     NAMES
48830cb9e317   eeb6ee3f44bd                 "/bin/bash"              12 minutes ago   Up 12 minutes                                                                                                                                                                                                             centos7-bak
#进入容器,开启一个终端
[root@localhost zph]# docker exec -it 48830cb9e317  /bin/bash

7.start 启动 stop 停止 restart 重启容器 exit 退出容器 

#docker ps -a: 查看所有容器(包括正在运行的以及被销毁的)
#docker start: 容器名/容器id 启动容器
#docker stop: 容器名/容器id 停止容器
#docker restart: 容器名/容器id 重启容器
#退出容器
# exit: 容器停止并退出
# ctrl+p+q：容器不停止退出

8.删除容器

#docker rm 容器名/容器id :删除一个已经停止的容器,如果删除的容器在运行中,会弹出一个警告
#docker rm -f 容器名/容器id :强制删除一个容器,不管是否在运行
#docker rm -f $(docker ps -q) :删除所有容器()docker ps -q: 获取容器id)
#docker rm $(docker ps -qf status=exited) :根据容器的状态，删除 Exited 状态的容器(docker ps -qf status=exited:筛选获取status=exited的容器id)

9.docker ps讲解

[root@localhost zph]# docker ps  --help

Usage:  docker ps [OPTIONS]

List containers

Options:
  -a, --all             Show all containers (default shows just running):展示所有容器
  -f, --filter filter   Filter output based on conditions provided:筛选
      --format string   Pretty-print containers using a Go template
  -n, --last int        Show n last created containers (includes all states) (default -1)
  -l, --latest          Show the latest created container (includes all states)
      --no-trunc        Don't truncate output
  -q, --quiet           Only display container IDs:展示容器id
  -s, --size            Display total file sizes

10查看容器操作日志

#docker logs 帮助文档
[root@localhost zph]# docker logs --help

Usage:  docker logs [OPTIONS] CONTAINER

Fetch the logs of a container

Options:
      --details        Show extra details provided to logs
  -f, --follow         Follow log output: 跟踪日志输出
      --since string   Show logs since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes) :显示某个开始时间的所有日志
  -n, --tail string    Number of lines to show from the end of the logs (default "all"):仅列出最新 N 条容器日
  -t, --timestamps     Show timestamps:显示时间戳
      --until string   Show logs before a timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)

#运行容器,给容器取一个别名,并进入容器的bash
[root@localhost zph]# docker run -it --name centos7 eeb6ee3f44bd /bin/bash
[root@63b354d40a1a /]# 
[root@63b354d40a1a /]# cd /home/
[root@63b354d40a1a home]# ll
total 0
[root@63b354d40a1a home]# mkdir git
[root@63b354d40a1a home]# cd git/
[root@63b354d40a1a git]# touch text.txt
[root@63b354d40a1a git]# ll
total 0
-rw-r--r-- 1 root root 0 Oct 24 15:26 text.txt
#执行ctrl+q+p:退出不停止容器操作
[root@63b354d40a1a git]# ^P[root@localhost zph]#
#查看正在运行的容器
[root@localhost zph]# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED              STATUS              PORTS     NAMES
63b354d40a1a   eeb6ee3f44bd   "/bin/bash"   About a minute ago   Up About a minute             centos7
#查看进入容器后的操作日志
[root@localhost zph]# docker logs 63b354d40a1a
[root@63b354d40a1a /]# 
[root@63b354d40a1a /]# cd /home/
[root@63b354d40a1a home]# ll
total 0
[root@63b354d40a1a home]# mkdir git
[root@63b354d40a1a home]# cd git/
[root@63b354d40a1a git]# touch text.txt
[root@63b354d40a1a git]# ll
total 0
-rw-r--r-- 1 root root 0 Oct 24 15:26 text.txt
[root@localhost zph]# 

11.docker commit 容器转换为镜像

镜像是没有写入权限的，但是可以修改容器把容器制作为镜像,通过镜像启动一个容器 给容器写入内容,安装相关的软件,然后把这个容器转换为镜像,然后打包上传到hub,别人就可以使用该镜像了,以alpine为例:

#拉取alpine镜像
[root@localhost zph]# docker pull alpine
Using default tag: latest
latest: Pulling from library/alpine
96526aa774ef: Pull complete 
Digest: sha256:eece025e432126ce23f223450a0326fbebde39cdf496a85d8c016293fc851978
Status: Downloaded newer image for alpine:latest
docker.io/library/alpine:latest

#查看是否存在alpine镜像
[root@localhost zph]# docker images
REPOSITORY         TAG                 IMAGE ID       CREATED         SIZE
alpine             latest              8ca4688f4f35   3 weeks ago     7.34MB

#运行alpine镜像,启动容器,并给容器命名,执行/bin/bash命令
[root@localhost zph]# docker run -it --name myalpine 8ca4688f4f35 /bin/bash
docker: Error response from daemon: OCI runtime create failed: container_linux.go:380: starting container process caused: exec: "/bin/bash": stat /bin/bash: no such file or directory: unknown.
#上面报错了: 提示没有/bin/bash这个命令

#重新启动容器,执行/bin/sh命令
[root@localhost zph]# docker run -it --name myalpine 8ca4688f4f35 /bin/sh
docker: Error response from daemon: Conflict. The container name "/myalpine" is already in use by container "959ece20098efb44b3c1744bb5df49a4d4caa78c362fd0eacc22fc53494f9f65". You have to remove (or rename) that container to be able to reuse that name.
#还是报错了:提示容器已经存在,容器名称存在了

#通过docker ps -a 查看,果然刚才启动的容器存在,解决办法:删除这个容器
root@localhost zph]# docker ps -a
CONTAINER ID   IMAGE          COMMAND                  CREATED          STATUS       PORTS     NAMES
959ece20098e   8ca4688f4f35   "/bin/bash"              40 seconds ago   Created                myalpine

#删除容器
[root@localhost zph]# docker rm 959ece20098e
959ece20098e

#重新执行镜像,启动容器,并执行/bin/sh 命令,然后在容器中写入内容,退出
[root@localhost zph]# docker run -it --name myalpine 8ca4688f4f35 /bin/sh
/ # cd root/
~ # ls
~ # echo test docker commit > test.txt
~ # ls
test.txt
~ # exit

#查看容器:发现myalpine已经退出,因为执行了exit,没问题
[root@localhost zph]# docker ps -a
CONTAINER ID   IMAGE          COMMAND                  CREATED              STATUS                      PORTS     NAMES
c37dce69c265   8ca4688f4f35   "/bin/sh"                About a minute ago   Exited (0) 22 seconds ago             myalpine

#把myalpine制作成镜像,使用docker commit 命令
#查看docker commit命令文档: docker commit [参数:-a,-c,...] 容器名/容器id 镜像名[:版本]
[root@localhost zph]# docker commit --help

Usage:  docker commit [OPTIONS] CONTAINER [REPOSITORY[:TAG]]

Create a new image from a container's changes

Options:
  -a, --author string    Author (e.g., "John Hannibal Smith ")
  -c, --change list      Apply Dockerfile instruction to the created image
  -m, --message string   Commit message
  -p, --pause            Pause container during commit (default true)


#制作镜像
[root@localhost zph]# docker commit c37dce69c265 docker.io/library/myalpine:v1
sha256:dd14c18efe091413581205f414dacca80d954e85cfb28208e7e610e1fb3c4f6e
#查看是否制作镜像成功
[root@localhost zph]# docker images
REPOSITORY                       TAG                 IMAGE ID       CREATED              SIZE
myalpine                         v1                  dd14c18efe09   14 seconds ago       7.34MB
#上面存在myalpine:v1,说明制作镜像成功了

#验证镜像: 运行镜像,开启这个容器
[root@localhost zph]# docker run -it -d --name myalpine.v1 dd14c18efe09 /bin/sh
cde912eb360c67b8becd8d70562929b08205440f8ba552b6eea80e51ebb20f78
#查看这个容器是否启动
[root@localhost zph]# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED         STATUS         PORTS     NAMES
cde912eb360c   dd14c18efe09   "/bin/sh"     9 seconds ago   Up 5 seconds             myalpine.v1

#进入容器验证
[root@localhost zph]# docker exec -it cde912eb360c /bin/sh
/ # cd root/
~ # ls
test.txt
~ # cat test.txt 
test docker commit
~ # exit
#里面有创建的text.txt,说明镜像创建成功

12.镜像的导入导出

可以把制作好的镜像发布到 dockerHub上，也可以把制作好的镜像导出发给别人

#查看所有镜像
[root@localhost zph]# docker images
REPOSITORY                       TAG                 IMAGE ID       CREATED         SIZE
myalpine                         v1                  dd14c18efe09   14 hours ago    7.34MB

#导出镜像
[root@localhost zph]# docker save myalpine > myalpine.tar
[root@localhost zph]# ll
总用量 7464
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 公共
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 模板
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 视频
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 图片
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 文档
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 下载
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 音乐
drwxr-xr-x. 2 zph  zph        6 12月 23 2021 桌面
-rw-r--r--  1 root root 7641600 10月 25 07:26 myalpine.tar

#删除镜像
[root@localhost zph]# docker rmi dd14c18efe09

#查看所有镜像
[root@localhost zph]# docker images
REPOSITORY                       TAG                 IMAGE ID       CREATED         SIZE

#导入镜像
[root@localhost zph]# docker load < myalpine.tar 
Loaded image: myalpine:v1

#查看所有镜像
[root@localhost zph]# docker images
REPOSITORY                       TAG                 IMAGE ID       CREATED         SIZE
myalpine                         v1                  dd14c18efe09   14 hours ago    7.34MB

#校验镜像是否成功
[root@localhost zph]# docker run -it --name myalpine.v1 dd14c18efe09 /bin/bash
#不报错就成功了

13.docker cp 实现数据拷贝

docker cp :用于容器与主机之间的数据拷贝

[root@localhost zph]# docker cp --help

Usage:  docker cp [OPTIONS] CONTAINER:SRC_PATH DEST_PATH|-
	docker cp [OPTIONS] SRC_PATH|- CONTAINER:DEST_PATH

Copy files/folders between a container and the local filesystem

Use '-' as the source to read a tar archive from stdin
and extract it to a directory destination in a container.
Use '-' as the destination to stream a tar archive of a
container source to stdout.

Options:
  -a, --archive       Archive mode (copy all uid/gid information)
  -L, --follow-link   Always follow symbol link in SRC_PATH

 

#查看目录
[root@localhost zph]# pwd
/home/zph

#创建文件夹
[root@localhost zph]# mkdir www
[root@localhost zph]# cd www/
[root@localhost www]# ll
总用量 0

#创建文件并写入数据
[root@localhost www]# echo test.docker > test.txt
[root@localhost www]# ll
总用量 4
-rw-r--r-- 1 root root 12 10月 25 07:51 test.txt
[root@localhost www]# cd ..

#查看images
[root@localhost zph]# docker images
REPOSITORY                       TAG                 IMAGE ID       CREATED         SIZE
centos                           7                   eeb6ee3f44bd   2 years ago     204MB

#查看运行的容器
[root@localhost zph]# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED        STATUS        PORTS     NAMES
63b354d40a1a   eeb6ee3f44bd   "/bin/bash"   23 hours ago   Up 23 hours             centos7

#进入容器 
[root@localhost zph]# docker exec -it 63b354d40a1a /bin/bash

#查看/下是否存在www目录:发现不存在该目录
[root@63b354d40a1a /]# ll
total 12
-rw-r--r--   1 root root 12114 Nov 13  2020 anaconda-post.log
lrwxrwxrwx   1 root root     7 Nov 13  2020 bin -> usr/bin
drwxr-xr-x   5 root root   360 Oct 24 15:25 dev
drwxr-xr-x   1 root root    66 Oct 24 15:24 etc
drwxr-xr-x   1 root root    17 Oct 24 15:26 home
lrwxrwxrwx   1 root root     7 Nov 13  2020 lib -> usr/lib
lrwxrwxrwx   1 root root     9 Nov 13  2020 lib64 -> usr/lib64
drwxr-xr-x   2 root root     6 Apr 11  2018 media
drwxr-xr-x   2 root root     6 Apr 11  2018 mnt
drwxr-xr-x   2 root root     6 Apr 11  2018 opt
dr-xr-xr-x 255 root root     0 Oct 24 15:24 proc
dr-xr-x---   2 root root   114 Nov 13  2020 root
drwxr-xr-x  11 root root   148 Nov 13  2020 run
lrwxrwxrwx   1 root root     8 Nov 13  2020 sbin -> usr/sbin
drwxr-xr-x   2 root root     6 Apr 11  2018 srv
dr-xr-xr-x  13 root root     0 Oct 24 15:24 sys
drwxrwxrwt   7 root root   132 Nov 13  2020 tmp
drwxr-xr-x  13 root root   155 Nov 13  2020 usr
drwxr-xr-x  18 root root   238 Nov 13  2020 var

#退出
[root@63b354d40a1a /]# exit
exit

#cp /home/zph/www/目录下的所有文件到容器的/下
[root@localhost zph]# docker cp /home/zph/www/ 63b354d40a1a:/

#进入容器查看是否cp成功
[root@localhost zph]# docker exec -it 63b354d40a1a /bin/bash

#ll查看:发现存在www,说明cp成功了
[root@63b354d40a1a /]# ll
total 12
-rw-r--r--   1 root root 12114 Nov 13  2020 anaconda-post.log
lrwxrwxrwx   1 root root     7 Nov 13  2020 bin -> usr/bin
drwxr-xr-x   5 root root   360 Oct 24 15:25 dev
drwxr-xr-x   1 root root    66 Oct 24 15:24 etc
drwxr-xr-x   1 root root    17 Oct 24 15:26 home
lrwxrwxrwx   1 root root     7 Nov 13  2020 lib -> usr/lib
lrwxrwxrwx   1 root root     9 Nov 13  2020 lib64 -> usr/lib64
drwxr-xr-x   2 root root     6 Apr 11  2018 media
drwxr-xr-x   2 root root     6 Apr 11  2018 mnt
drwxr-xr-x   2 root root     6 Apr 11  2018 opt
dr-xr-xr-x 255 root root     0 Oct 24 15:24 proc
dr-xr-x---   1 root root    27 Oct 25 14:53 root
drwxr-xr-x  11 root root   148 Nov 13  2020 run
lrwxrwxrwx   1 root root     8 Nov 13  2020 sbin -> usr/sbin
drwxr-xr-x   2 root root     6 Apr 11  2018 srv
dr-xr-xr-x  13 root root     0 Oct 24 15:24 sys
drwxrwxrwt   7 root root   132 Nov 13  2020 tmp
drwxr-xr-x  13 root root   155 Nov 13  2020 usr
drwxr-xr-x  18 root root   238 Nov 13  2020 var
drwxr-xr-x   2 root root    22 Oct 25 14:51 www
[root@63b354d40a1a /]# cd www/
[root@63b354d40a1a www]# ll
total 4
-rw-r--r-- 1 root root 12 Oct 25 14:51 test.txt

#在www下新建文件并写入数据,然后退出
[root@63b354d40a1a www]# echo test2.com > test2.txt
[root@63b354d40a1a www]# exit
exit

#cp容器中的www下的所有文件到系统的/var下
[root@localhost zph]# docker cp 63b354d40a1a:www/ /var

#查看是否cp成功:发现成功了
[root@localhost zph]# ll /var/www/
总用量 8
-rw-r--r-- 1 root root 10 10月 25 07:54 test2.txt
-rw-r--r-- 1 root root 12 10月 25 07:51 test.txt
[root@localhost zph]# 

[上一节][Docker]一.Docker 简介与安装