容器运行应用及Docker命令

文章目录

一、使用容器运行Nginx应用
- 1_使用docker run命令运行Nginx应用
- - 1 观察下载容器镜像过程
  - 2 观察容器运行情况
- 2_访问容器中运行的Nginx服务
- - 1 确认容器IP地址
  - 2 容器网络说明
  - 3 使用curl命令访问
二、Docker命令
- 1_Docker命令获取帮助方法
- 2_Docker官网提供的命令说明
- 3_docker命令应用
- - 1 docker run
  - 2 docker ps
  - 3 docker inspect
  - 4 docker exec
  - 5 docker attach
  - 6 docker stop
  - 7 docker start
  - 8 docker top
  - 9 docker rm

一、使用容器运行Nginx应用

1_使用docker run命令运行Nginx应用

1 观察下载容器镜像过程

查找本地容器镜像文件

执行命令过程一：下载容器镜像

[root@localhost ~]# docker run -d nginx:latest
Unable to find image 'nginx:latest' locally
latest: Pulling from library/nginx
a2abf6c4d29d: Downloading  1.966MB/31.36MB 下载中
a9edb18cadd1: Downloading  1.572MB/25.35MB
589b7251471a: Download complete 下载完成
186b1aaa4aa6: Download complete
b4df32aa5a72: Waiting 等待下载
a0bcbecc962e: Waiting

执行命令过程二：下载容器镜像

[root@localhost ~]# docker run -d nginx:latest
Unable to find image 'nginx:latest' locally
latest: Pulling from library/nginx
a2abf6c4d29d: Downloading  22.87MB/31.36MB
a9edb18cadd1: Downloading  22.78MB/25.35MB
589b7251471a: Waiting
186b1aaa4aa6: Waiting
b4df32aa5a72: Waiting

执行命令过程三：下载容器镜像

[root@localhost ~]# docker run -d nginx:latest
Unable to find image 'nginx:latest' locally
latest: Pulling from library/nginx
a2abf6c4d29d: Pull complete 下载完成
a9edb18cadd1: Pull complete
589b7251471a: Pull complete
186b1aaa4aa6: Pull complete
b4df32aa5a72: Waiting 等待下载

2 观察容器运行情况

[root@localhost ~]# docker run -d nginx:latest
9834c8c18a7c7c89ab0ea4119d11bafe9c18313c8006bc02ce57ff54d9a1cc0c

命令解释	说明
docker run	启动一个容器
-d	把容器镜像中需要执行的命令以daemon（守护进程）的方式运行
nginx	应用容器镜像的名称，通常表示该镜像为某一个软件
latest	表示上述容器镜像的版本，表示最新版本，用户可自定义其标识，例如v1或v2等

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE        COMMAND                  CREATED          STATUS        PORTS     NAMES
9834c8c18a7c   nginx:latest "/docker-entrypoint.…"   24 seconds ago   Up 23 seconds 80/tcp condescending_pare

命令解释

docker ps 类似于Linux系统的ps命令，查看正在运行的容器，如果想查看没有运行的容器，需要在此命令后使用 --all

输出内容解释

CONTAINERID	IMAGE	COMMAND	CREATED	STATUS	PORTS	NAMES
9834c8c18a7c	nginx:latest	“/docker-entrypoint.…”	24 seconds ago	Up 23 seconds	80/tcp	condescending_pare
容器ID	容器镜像	容器中运行的命令	容器创建时间	容器状态	容器提供访问应用端口	容器名称

2_访问容器中运行的Nginx服务

1 确认容器IP地址

实际工作中不需要此步操作，9834 是容器ID缩写。

[root@localhost ~]# docker inspect 9834c8c18a7c"GlobalIPv6Address": "","GlobalIPv6PrefixLen": 0,"IPAddress": "172.17.0.2", 容器IP地址"IPPrefixLen": 16,"IPv6Gateway": "","MacAddress": "02:42:ac:11:00:02","Networks": {"bridge": {"IPAMConfig": null,"Links": null,"Aliases": null,"NetworkID": "d3de2fdbc30ee36a55c1431ef3ae4578392e552009f00b2019b4720735fe5a60","EndpointID": "d91f47c9f756ff22dc599a207164f2e9366bd0c530882ce0f08ae2278fb3d50c","Gateway": "172.17.0.1","IPAddress": "172.17.0.2",   容器IP地址"IPPrefixLen": 16,"IPv6Gateway": "","GlobalIPv6Address": "","GlobalIPv6PrefixLen": 0,"MacAddress": "02:42:ac:11:00:02","DriverOpts": null}}}}
]

命令解释

docker inspect 为查看容器结构信息命令

9834 为前面生成的容器ID号前4位，使用这个ID号时，由于其较长，使用时能最短识别即可。

2 容器网络说明

在这里插入图片描述

查看系统网络接口信息

ip a s # ip addr show

docker0网桥，用于为容器提供桥接，转发到主机之外的网络

5: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group defaultlink/ether 02:42:d5:c3:d4:cc brd ff:ff:ff:ff:ff:ffinet 172.17.0.1/16 brd 172.17.255.255 scope global docker0valid_lft forever preferred_lft foreverinet6 fe80::42:d5ff:fec3:d4cc/64 scope linkvalid_lft forever preferred_lft forever

与容器中的虚拟网络设备在同一个命名空间中，用于把容器中的网络连接到主机

9: veth393dece@if8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group defaultlink/ether 02:e3:11:58:54:0f brd ff:ff:ff:ff:ff:ff link-netnsid 0inet6 fe80::e3:11ff:fe58:540f/64 scope linkvalid_lft forever preferred_lft forever

3 使用curl命令访问

返回结果，表示访问成功！

[root@localhost ~]# curl 172.17.0.2
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p><p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p><p><em>Thank you for using nginx.</em></p>
</body>
</html>

二、Docker命令

1_Docker命令获取帮助方法

[root@localhost ~]# docker -h
Flag shorthand -h has been deprecated, use --helpUsage:  docker [OPTIONS] COMMANDA self-sufficient runtime for containersCommon Commands:run         Create and run a new container from an imageexec        Execute a command in a running containerps          List containersbuild       Build an image from a Dockerfilepull        Download an image from a registrypush        Upload an image to a registryimages      List imageslogin       Authenticate to a registrylogout      Log out from a registrysearch      Search Docker Hub for imagesversion     Show the Docker version informationinfo        Display system-wide informationManagement Commands:builder     Manage buildsbuildx*     Docker Buildxcompose*    Docker Composecontainer   Manage containerscontext     Manage contextsimage       Manage imagesmanifest    Manage Docker image manifests and manifest listsnetwork     Manage networksplugin      Manage pluginssystem      Manage Dockertrust       Manage trust on Docker imagesvolume      Manage volumesSwarm Commands:swarm       Manage SwarmCommands:attach      Attach local standard input, output, and error streams to a running containercommit      Create a new image from a container's changescp          Copy files/folders between a container and the local filesystemcreate      Create a new containerdiff        Inspect changes to files or directories on a container's filesystemevents      Get real time events from the serverexport      Export a container's filesystem as a tar archivehistory     Show the history of an imageimport      Import the contents from a tarball to create a filesystem imageinspect     Return low-level information on Docker objectskill        Kill one or more running containersload        Load an image from a tar archive or STDINlogs        Fetch the logs of a containerpause       Pause all processes within one or more containersport        List port mappings or a specific mapping for the containerrename      Rename a containerrestart     Restart one or more containersrm          Remove one or more containersrmi         Remove one or more imagessave        Save one or more images to a tar archive (streamed to STDOUT by default)start       Start one or more stopped containersstats       Display a live stream of container(s) resource usage statisticsstop        Stop one or more running containerstag         Create a tag TARGET_IMAGE that refers to SOURCE_IMAGEtop         Display the running processes of a containerunpause     Unpause all processes within one or more containersupdate      Update configuration of one or more containerswait        Block until one or more containers stop, then print their exit codesGlobal 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 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 quitRun 'docker COMMAND --help' for more information on a command.For more help on how to use Docker, head to https://docs.docker.com/go/guides/

2_Docker官网提供的命令说明

网址链接：https://docs.docker.com/reference/

在这里插入图片描述

3_docker命令应用

1 docker run

docker run -i -t --name c1 centos:latest bash
[root@948f234e22a1 /]#

命令	解释
docker run	运行一个命令在容器中，命令是主体，没有命令容器就会消亡
-i	交互式
-t	提供终端
–name c1	把将运行的容器命名为c1
centos:latest	使用centos最新版本容器镜像
bash	在容器中执行的命令

注意看主机名

[root@948f234e22a1 /]#

查看网络信息

[root@948f234e22a1 /]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft forever
12: eth0@if13: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group defaultlink/ether 02:42:ac:11:00:03 brd ff:ff:ff:ff:ff:ff link-netnsid 0inet 172.17.0.3/16 brd 172.17.255.255 scope global eth0valid_lft forever preferred_lft forever

查看进程

[root@948f234e22a1 /]# ps aux
USER        PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root          1  0.0  0.1  12036  2172 pts/0    Ss   09:58   0:00 bash
root         16  0.0  0.0  44652  1784 pts/0    R+   10:02   0:00 ps aux

查看用户

[root@948f234e22a1 /]# cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:65534:65534:Kernel Overflow User:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
systemd-coredump:x:999:997:systemd Core Dumper:/:/sbin/nologin
systemd-resolve:x:193:193:systemd Resolver:/:/sbin/nologin

查看目录(跟我们系统基本一样）

[root@948f234e22a1 /]# pwd
/
[root@948f234e22a1 /]# ls
bin  etc   lib    lost+found  mnt  proc  run   srv  tmp  var
dev  home  lib64  media       opt  root  sbin  sys  usr

退出命令执行，观察容器运行情况

[root@948f234e22a1 /]# exit
exit
[root@localhost ~]#

2 docker ps

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES

命令解释

docker ps 查看正在运行的容器，本案例由于没有命令在容器中运行，因此容器被停止了，所以本次查看没有结果。

[root@localhost ~]# docker ps --all
CONTAINER ID   IMAGE           COMMAND     CREATED             STATUS                         PORTS     NAMES
948f234e22a1   centos:latest   "bash"    10 minutes ago      Exited (0) 2 minutes ago                    c1

CONTAINERID	IMAGE	COMMAND	CREATED	STATUS	PORTS	NAMES
948f234e22a1	centos:latest	“bash”	10 minutes ago	Exited (0) 2 minutes ago		c1

命令解释

docker ps --all 可以查看正在运行的和停止运行的容器

3 docker inspect

[root@localhost ~]# docker run -it --name c2 centos:latest bash
[root@b4182fd1f2cc /]#

操作说明

在上述提示符处按住ctrl键，再按p键与q键，可以退出交互式的容器，容器会处于运行状态。

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE           COMMAND   CREATED              STATUS              PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"    About a minute ago   Up About a minute             c2

命令解释

可以看到容器处于运行状态

[root@localhost ~]# docker inspect c2
"Networks": {"bridge": {"IPAMConfig": null,"Links": null,"Aliases": null,"NetworkID": "d3de2fdbc30ee36a55c1431ef3ae4578392e552009f00b2019b4720735fe5a60","EndpointID": "d1a2b7609f2f73a6cac67229a4395eef293f695c0ac4fd6c9c9e6913c9c85c1c","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}}}}
]

命令解释

docker inpect 查看容器详细信息

4 docker exec

[root@localhost ~]# docker exec -it c2 ls /root
anaconda-ks.cfg  anaconda-post.log  original-ks.cfg

命令	解释
docker exec	在容器外实现与容器交互执行某命令
-it	交互式
c2	正在运行的容器名称
ls /root	在正在运行的容器中运行相关的命令

下面命令与上面命令执行效果一致

[root@localhost ~]# docker exec c2 ls /root
anaconda-ks.cfg
anaconda-post.log
original-ks.cfg

5 docker attach

查看正在运行的容器

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE           COMMAND   CREATED         STATUS         PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"    8 minutes ago   Up 8 minutes             c2
ef02ada6ba49   nginx:latest    "/docker-entrypoint.…"   2 hours ago      Up 4 seconds   80/tcp    cool_bardeen

进入容器内部

[root@localhost ~]# docker attach c2
[root@b4182fd1f2cc /]#

命令	解释
docker attach	类似于ssh命令，可以进入到容器中
c2	正在运行的容器名称

说明

docker attach 退出容器时，如不需要容器再运行，可直接使用exit退出；如需要容器继续运行，可使用ctrl+p+q

另外由于另外一个 nginx 容器并不是交互式的，所以不允许我们进入内部，如果尝试的话会卡住

docker attach cool_bardeen # 卡住,并且Ctrl+c退出时容器也会随之停止

6 docker stop

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE           COMMAND   CREATED          STATUS          PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"    11 minutes ago   Up 11 minutes             c2
[root@localhost ~]# docker stop b4182
b4182
[root@localhost ~]# docker ps --all
CONTAINER ID   IMAGE           COMMAND                   CREATED             STATUS                         PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"                    12 minutes ago      Exited (0) 28 seconds ago                c2

支持批量停止以及使用容器名称

7 docker start

[root@localhost ~]# docker ps --all
CONTAINER ID   IMAGE           COMMAND                   CREATED             STATUS                         PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"                    12 minutes ago      Exited (0) 28 seconds ago                c2
[root@localhost ~]# docker start b4182
b4182
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE           COMMAND   CREATED          STATUS          PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"    14 minutes ago   Up 16 seconds             c2

还可以批量开启，以及使用容器名称代替容器ID

8 docker top

在Docker Host查看容器中运行的进程信息

docker top c2

如下输出

UID	PID	PPID	C	STIME	TTY	TIME	CMD
root	394835	394784	0	18:37	pts/0	00:00:00	bash

命令解释

输出信息	说明
UID	容器中运行的命令用户ID
PID	容器中运行的命令PID
PPID	容器中运行的命令父PID，由于PPID是一个容器，此可指为容器在Docker Host中进程ID
C	占用CPU百分比
STIME	启动时间
TTY	运行所在的终端
TIME	运行时间
CMD	执行的命令

[root@localhost ~]# ps aux | grep 394784
root      394784  0.0  0.4 1237928 15756 ?       Sl   05:43   0:00 /usr/bin/containerd-shim-runc-v2 -namespace moby -id b4182fd1f2ccfea5799bd63206ed562c38e53b18c93def3a56262fd73122e8ab -address /run/containerd/containerd.sock
root      408828  0.0  0.0 221680  2304 pts/0    S+   05:47   0:00 grep --color=auto 394784
[root@localhost ~]# ps aux | grep 394835
root      394835  0.0  0.0  12052  3200 pts/0    Ss+  05:43   0:00 bash
root      399829  0.0  0.0 221680  2304 pts/0    S+   05:44   0:00 grep --color=auto 394835
[root@localhost ~]# docker exec -it c2 ps -ef
UID          PID    PPID  C STIME TTY          TIME CMD
root           1       0  0 21:43 pts/0    00:00:00 bash
root          14       0  0 21:45 pts/1    00:00:00 ps -ef

docker top 查看container内进程信息，指在docker host上查看，与docker exec -it c2 ps -ef不同。

另外一个容器中运行多个进程也是存在的，可以尝试去访问 nginx 看看。

9 docker rm

如果容器已停止，使用此命令可以直接删除；如果容器处于运行状态，则需要提前关闭容器后，再删除容器。

下面演示容器正在运行关闭后删除的方法。

指定删除容器

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE           COMMAND   CREATED          STATUS          PORTS     NAMES
b4182fd1f2cc   centos:latest   "bash"    30 minutes ago   Up 16 minutes             c2

停止容器

docker stop c2 # 或 docker stop b4182fd1f2cc

删除容器

docker rm c2 # 或 docker rm b4182fd1f2cc

批量删除容器

-a 与 --all 是等价的

[root@localhost ~]# docker ps -a 
CONTAINER ID   IMAGE           COMMAND                   CREATED             STATUS                        PORTS     NAMES
3bd60ca310ca   centos:latest   "bash"                    About an hour ago   Exited (127) 48 minutes ago             c1
c71fb30f25da   nginx:latest    "/docker-entrypoint.…"   2 hours ago         Exited (0) 2 hours ago                  zen_swirles
ef02ada6ba49   nginx:latest    "/docker-entrypoint.…"   2 hours ago         Exited (0) 20 minutes ago               cool_bardeen

批量删除容器：

docker ps --all | awk '{if (NR>=2){print $1}}' | xargs docker rm

上述命令可以把第一个命令执行的结果看作文本作为 awk 输入；awk 将从第二行开始，每行的第一个元素(元素以空格作为分隔)输出作为 xargs 的输入。