docker基础用法

什么是docker
docker中的容器：

lxc --> libcontainer --> runc

OCI&OCF

OCI
Open Container-initiative

由Linux基金会主导于2015年6月创立
旨在围绕容器格式和运行时制定一个开放的工业化标准
包含两个规格contains two specifications
运行时规范
图像规格

OCF
Open Container Format

runC 是一个 CLI 工具，用于根据 OCI 规范生成和运行容器

容器作为 runC 的子进程启动，可以嵌入到各种其他系统中，而无需运行守护程序

runC 建立在 libcontainer 之上，libcontainer 是支持数百万个 Docker 引擎安装的相同容器技术

docker提供了一个专门容纳容器镜像的站点：https://hub.docker.com

docker架构

docker镜像与镜像仓库

镜像是静态的，而容器是动态的，容器有其生命周期，镜像与容器的关系类似于程序与进程的关系。镜像类似于文件系统中的程序文件，而容器则类似于将一个程序运行起来的状态，也即进程。所以容器是可以删除的，容器被删除后其镜像是不会被删除的。

docker对象

使用 Docker 时，您正在创建和使用映像、容器、网络、卷、插件和其他对象。

IMAGES
镜像是一个只读模板，其中包含有关创建 docker 容器的说明。
通常，一个镜像基于另一个映像，并具有一些额外的自定义。
您可以创建自己的镜像，也可以只使用其他人创建并在注册表中发布的镜像。

CONTAINERS
连接器是图像的可运行实例。
您可以使用 Docker API 或 CLI 创建、运行、停止、移动或删除容器。
可以将容器连接到一个或多个网络，将存储附加到该网络，甚至可以根据其当前状态创建新镜像。

安装及使用docker

docker安装

https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo 阿里源链接

[root@localhost yum.repos.d]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

[root@localhost yum.repos.d]# ls
CentOS-Base.repo  epel-modular.repo  epel-testing-modular.repo
docker-ce.repo    epel.repo          epel-testing.repo


[root@localhost ~]# dnf -y install docker-ce

docker加速

docker-ce的配置文件是/etc/docker/daemon.json，此文件默认不存在，需要我们手动创建并进行配置，而docker的加速就是通过配置此文件来实现的。

docker的加速有多种方式：

docker cn
中国科技大学加速器
阿里云加速器（需要通过阿里云开发者平台注册帐号，免费使用个人私有的加速器）

设置开机自启

[root@localhost ~]# systemctl enable --now docker
Created symlink /etc/systemd/system/multi-user.target.wants/docker.service → /usr/lib/systemd/system/docker.service.
[root@localhost ~]# systemctl status docker
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor pre>
   Active: active (running) since Sun 2022-04-24 16:40:47 CST; 14s ago
     Docs: https://docs.docker.com
 Main PID: 5026 (dockerd)
    Tasks: 8
   Memory: 31.2M
   CGroup: /system.slice/docker.service
           └─5026 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/conta>

创建一个阿里云加速器

把阿里云镜像写到daemon.json

[root@localhost ~]# cd /etc/docker/
[root@localhost docker]# ls
key.json
[root@localhost docker]# vim daemon.json

{
          "registry-mirrors": ["https://ay24c8ru.mirror.aliyuncs.com"]
}
~                                                                              
~                    

[root@localhost docker]# systemctl daemon-reload
[root@localhost docker]# systemctl restart docker

docker info 可以看到运行环境

[root@localhost docker]# docker info
Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Registry Mirrors:
  https://ay24c8ru.mirror.aliyuncs.com/
 Live Restore Enabled: false

//看到https就说明加速器配置成功


[root@localhost ~]# docker version
Client: Docker Engine - Community
 Version:           20.10.14
 API version:       1.41
 Go version:        go1.16.15
 Git commit:        a224086
 Built:             Thu Mar 24 01:47:44 2022
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.14
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.16.15
  Git commit:       87a90dc
  Built:            Thu Mar 24 01:46:10 2022
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.5.11
  GitCommit:        3df54a852345ae127d1fa3092b95168e4a88e2f8
 runc:
  Version:          1.0.3
  GitCommit:        v1.0.3-0-gf46b6ba
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0
//查看他的版本号

[root@localhost ~]# docker search seancheng1002/httpd
NAME                  DESCRIPTION   STARS     OFFICIAL   AUTOMATED
seancheng1002/httpd 
//可以搜索别人在docker仓库做的镜像


[root@localhost ~]# docker search httpd
NAME                                    DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
httpd                                   The Apache HTTP Server Project                  3975      [OK]       
centos/httpd-24-centos7                 Platform for running Apache httpd 2.4 or bui…   44                   
centos/httpd                                                                            35                   [OK]
solsson/httpd-openidc                   mod_auth_openidc on official httpd image, ve…   2                    [OK]
hypoport/httpd-cgi                      httpd-cgi                                       2                    [OK]
dariko/httpd-rproxy-ldap                Apache httpd reverse proxy with LDAP authent…   1                    [OK]
manageiq/httpd                          Container with httpd, built on CentOS for Ma…   1                    [OK]
dockerpinata/httpd                                                                      1                    
publici/httpd                           httpd:latest                                    1                    [OK]
clearlinux/httpd                        httpd HyperText Transfer Protocol (HTTP) ser…   1                    
jonathanheilmann/httpd-alpine-rewrite   httpd:alpine with enabled mod_rewrite           1                    [OK]
inanimate/httpd-ssl                     A play container with httpd, ssl enabled, an…   1                    [OK]
centos/httpd-24-centos8                                                                 1                    
lead4good/httpd-fpm                     httpd server which connects via fcgi proxy h…   1                    [OK]
manageiq/httpd_configmap_generator      Httpd Configmap Generator                       0                    [OK]
e2eteam/httpd                                                                           0                    
paketobuildpacks/httpd                                                                  0                    
httpdocker/kubia-unhealthy                                                              0                    
httpdss/archerysec                      ArcherySec repository                           0                    [OK]
19022021/httpd-connection_test          This httpd image will test the connectivity …   0                    
patrickha/httpd-err                                                                     0                    
httpdocker/kubia                                                                        0                    
sandeep1988/httpd-new                   httpd-new                                       0                    
itsziget/httpd24                        Extended HTTPD Docker image based on the off…   0                    [OK]
manasip/httpd                                                                           0                    
//官方的镜像

docker常用操作

命令	功能
docker search	Search the Docker Hub for images
docker pull	Pull an image or a repository from a registry
docker images	List images
docker create	Create a new conntainer
docker start	Start one or more stopped containers
docker run	Run a command in a new container
docker attach	Attach to a runninng container
docker ps	List containers
docker logs	Fetch the logs of a container
docker restart	Restart a container
docker stop	Stop one or more running containers
docker kill	Kill one or more running containers
docker rm	Remove onne or more containers
docker exec	Run a command in a running container
docker info	Display system-wide information
docker inspect	Return low-level information on Docker objects

[root@localhost ~]# ls /var/lib/docker
buildkit    image    overlay2  runtimes  tmp    volumes
containers  network  plugins   swarm     trust

[root@localhost ~]# docker images
REPOSITORY   TAG       IMAGE ID   CREATED   SIZE

//目前时空的
[root@localhost ~]# docker pull httpd
//拉最新版本的 如果要指定版本在httpd后面跟上版本号即可

[root@localhost ~]# docker images
REPOSITORY   TAG       IMAGE ID       CREATED      SIZE
httpd        latest    c30a46771695   4 days ago   144MB
//可以看到多了httpd

[root@localhost ~]# docker pull httpd:2.4.53
2.4.53: Pulling from library/httpd

[root@localhost ~]# docker images
REPOSITORY   TAG       IMAGE ID       CREATED      SIZE
httpd        2.4.53    c30a46771695   4 days ago   144MB
httpd        latest    c30a46771695   4 days ago   144MB

创建一个httpd容器

[root@localhost ~]# docker create --name web -p 80:80 httpd
b9f1f8002b43430d9fd75314340281e5b9e05981f24e6191b476a6111b913d0e

查看容器的状态


[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND              CREATED          STATUS    PORTS     NAMES
b9f1f8002b43   httpd     "httpd-foreground"   46 seconds ago   Created             web

启动docker


[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND              CREATED          STATUS    PORTS     NAMES
b9f1f8002b43   httpd     "httpd-foreground"   46 seconds ago   Created             web


[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND              CREATED         STATUS         PORTS                               NAMES
b9f1f8002b43   httpd     "httpd-foreground"   2 minutes ago   Up 5 seconds   0.0.0.0:80->80/tcp, :::80->80/tcp   web

关闭防火墙

[root@localhost ~]# systemctl disable --now firewalld
Removed /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@localhost ~]# vi /etc/selinux/config 


# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=disabled

[root@localhost ~]# setenforce 0

访问

停止

[root@localhost ~]# docker stop web
web
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND              CREATED         STATUS                     PORTS     NAMES
b9f1f8002b43   httpd     "httpd-foreground"   5 minutes ago   Exited (0) 8 seconds ago             web

防火墙放行的方式

[root@localhost ~]# firewall-cmd --add-rich-rule 'rule family=ipv4 source address=0.0.0.0/0 service name=http accept' --permanent
success

[root@localhost ~]# firewall-cmd --list-all
public (active)
  target: default
  icmp-block-inversion: no
  interfaces: ens33
  sources: 
  services: cockpit dhcpv6-client ssh
  ports: 
  protocols: 
  forward: no
  masquerade: no
  forward-ports: 
  source-ports: 
  icmp-blocks: 
  rich rules: 
	rule family="ipv4" source address="0.0.0.0/0" service name="http" accept

重启

[root@localhost ~]# docker restart web
web
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND              CREATED          STATUS         PORTS                               NAMES
b9f1f8002b43   httpd     "httpd-foreground"   19 minutes ago   Up 5 seconds   0.0.0.0:80->80/tcp, :::80->80/tcp   web

杀掉进程

[root@localhost ~]# docker kill web
web
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND              CREATED          STATUS                       PORTS     NAMES
b9f1f8002b43   httpd     "httpd-foreground"   20 minutes ago   Exited (137) 8 seconds ago             web

查看日志

[root@localhost ~]# docker logs web
192.168.80.1 - - [24/Apr/2022:10:05:12 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:05:13 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:05:14 +0000] "GET / HTTP/1.1" 304 -
//访问的状态

192.168.80.1 - - [24/Apr/2022:10:05:12 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:05:13 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:05:14 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:06:04 +0000] "-" 408 -
192.168.80.1 - - [24/Apr/2022:10:06:40 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:06:41 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:06:42 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:06:43 +0000] "GET / HTTP/1.1" 304 -
192.168.80.1 - - [24/Apr/2022:10:06:56 +0000] "GET /sda HTTP/1.1" 404 196
192.168.80.1 - - [24/Apr/2022:10:06:58 +0000] "GET /sda HTTP/1.1" 404 196

rm删除容器

[root@localhost ~]# docker rm -f b9f1f8002b43
b9f1f8002b43
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES

[root@localhost ~]# docker images
REPOSITORY   TAG       IMAGE ID       CREATED      SIZE
httpd        2.4.53    c30a46771695   4 days ago   144MB
httpd        latest    c30a46771695   4 days ago   144MB

docker run 直接创建运行进入

[root@localhost ~]# docker run -it --name test busybox /bin/sh
Unable to find image 'busybox:latest' locally
latest: Pulling from library/busybox
5cc84ad355aa: Pull complete 
Digest: sha256:5acba83a746c7608ed544dc1533b87c737a0b0fb730301639a0179f9344b1678
Status: Downloaded newer image for busybox:latest
/ # 
/ # ip a
1: lo:  mtu 65536 qdisc noqueue qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
14: eth0@if15:  mtu 1500 qdisc noqueue 
    link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.2/16 brd 172.17.255.255 scope global eth0
       valid_lft forever preferred_lft forever
/ # exit
//退出

容器停掉的情况下进去退出并运行

[root@localhost ~]# docker exec -it test /bin/sh
/ # ip a
1: lo:  mtu 65536 qdisc noqueue qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
18: eth0@if19:  mtu 1500 qdisc noqueue 
    link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.2/16 brd 172.17.255.255 scope global eth0
       valid_lft forever preferred_lft forever
/ # exit
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND     CREATED         STATUS          PORTS     NAMES
045b410c8557   busybox   "/bin/sh"   5 minutes ago   Up 32 seconds             test

docker基础用法

什么是docker docker中的容器： lxc --> libcontainer --> runc

OCI&OCF

OCI Open Container-initiative 由Linux基金会主导于2015年6月创立旨在围绕容器格式和运行时制定一个开放的工业化标准包含两个规格contains two specifications 运行时规范图像规格

docker架构

安装及使用docker

Linux相关栏目本月热门文章

什么是docker
docker中的容器：

lxc --> libcontainer --> runc

OCI
Open Container-initiative

由Linux基金会主导于2015年6月创立
旨在围绕容器格式和运行时制定一个开放的工业化标准
包含两个规格contains two specifications
运行时规范
图像规格