docker应用

打包传输

1.将镜像打包

#查看帮助文件

docker --help

#找到save，可以将镜像保存为一个tar包

docker save --help

#查看save使用方式

#查看现有的镜像

docker images

# docker save --output centos.tar centos:latest

ls

...centos.tar...

可以将tar发送给其他用户，也可以作为备份

删除镜像

[root@docker ~]# docker rmi centos:latest
Error response from daemon: conflict: unable to remove repository reference "centos:latest" (must force) - container 5b068251f855 is using its referenced image 5d0da3dc9764
#如果有这个镜像生成的容器正在使用，那么就无法使用rmi移除镜像

#删除容器，退出容器的up状态

docker rm c0

[root@docker ~]# docker rm c0
c0

[root@docker ~]# docker ps --all #使用docker ps --all确定没有镜像
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
[root@docker ~]# docker rmi centos:latest
Untagged: centos:latest
Untagged: centos@sha256:a27fd8080b517143cbbbab9dfb7c8571c40d67d534bbdee55bd6c473f432b177
Deleted: sha256:5d0da3dc976460b72c77d94c8a1ad043720b0416bfc16c52c45d4847e53fadb6
Deleted: sha256:74ddd0ec08fa43d09f32636ba91a0a3053b02cb4627c35051aff89f853606b59
[root@docker ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE

从tar中引入镜像

docker --help

docker load --help

docker load -i centos.tar centos:latest

[root@docker ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
[root@docker ~]# ls
anaconda-ks.cfg centos.tar
[root@docker ~]# docker load --help

Usage: docker load [OPTIONS]

Load an image from a tar archive or STDIN

Aliases:
docker image load, docker load

Options:
-i, --input string Read from tar archive file, instead of STDIN
-q, --quiet Suppress the load output
[root@docker ~]# docker load -i centos.tar
74ddd0ec08fa: Loading layer 238.6MB/238.6MB
Loaded image: centos:latest
[root@docker ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
centos latest 5d0da3dc9764 2 years ago 231MB

打开一个新的容器

docker run -it --name c0 centos:latest /bin/bash

ctrl ^p^q 退出但不关闭

创建镜像

#查看所有的容器

docker ps --all

#停用并且删除容器

docker stop c1 && docker rm c1

容器导出镜像

1.从容器导出tar包

#查看帮助文档

docker --help

docker export --help

#使用指令

docker export -o centos_yum.tar c0 将容器导出为tar包

#查看新生成的tar包

2.从tar包导入镜像

#查看帮助

docker --help

docker import --help

#使用导入

docker import -m 说明内容 centos_yum.tar centos:yum

#查看镜像

docker images

#这个镜像不需要我们配置yum

练习：

做一个带httpd服务的镜像

docker run -it --name c100 centos:yum /bin/bash

yum -y install httpd

echo "aaabbbccc" > /var/www/html/index.html

httpd -k start

curl ^P^Q

docker export -o centos_httpd.tar c100

docker import -m httpd centos_httpd.tar centos:httpd

实操：

[root@docker httpd]# docker run -it --name c100 centos:yum /bin/bash
[root@f223078b317b /]# yum -y install httpd
[root@f223078b317b /]# echo "aaabbbcccddd" > /var/www/html/index.html
[root@f223078b317b /]# httpd -k start
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 172.17.0.2. Set the 'ServerName' directive globally to suppress this message
[root@f223078b317b /]# curl localhost
aaabbbcccddd
[root@f223078b317b /]# [root@docker httpd]#
[root@docker httpd]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f223078b317b centos:yum "/bin/bash" 2 minutes ago Up 2 minutes c100
[root@docker httpd]# docker export -o centos_httpd c100
[root@docker httpd]# ls
centos_httpd dockerfile index.html
[root@docker httpd]# docker import -m intrduce centos_httpd centos:httpd
sha256:4bec8f3517a5f9c7934e9b9c61db1b7eec106b5ab4375b905d8dcfbf93707a86
[root@docker httpd]# docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
centos httpd 4bec8f3517a5 21 seconds ago 309MB
centos yum 3e62c6e9639e 3 hours ago 260MB
centos 7 eeb6ee3f44bd 2 years ago 204MB
centos latest 5d0da3dc9764 2 years ago 231MB
[root@docker httpd]# docker run -it --name c101 centos:httpd /bin/bash 启动一个容器之后，可以启动httpd服务
[root@17f686ad3194 /]# httpd -k start
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 172.17.0.3. Set the 'ServerName' directive globally to suppress this message
[root@17f686ad3194 /]# curl localhost
aaabbbcccddd

[root@docker ~]# docker inspect --help 查看语法