Docker实践:Centos下安装Docker并简单的使用

1 环境介绍

版本信息:

[root@localhost]#  cat /proc/version

Linux version 3.10.0-514.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-11) (GCC) ) #1 SMP Tue Nov 22 16:42:41 UTC 2016

[root@localhost jenkins]# cat  /etc/redhat-release

CentOS Linux release 7.3.1611 (Core)

# Centos系统是离线的,但是可以通过代理访问网络,否则,就无法pull Image了.

# 查看yum list中是否有docker安装包:

[root@localhost home]# yum list | grep docker

docker.x86_64                              2:1.12.6-32.git88a4867.el7.centos

docker-client.x86_64                       2:1.12.6-32.git88a4867.el7.centos

docker-common.x86_64                       2:1.12.6-32.git88a4867.el7.centos

…

[root@localhost home]#

2安装Docker

# install

sudo yum install -y docker.x86_64

#  yum install docker

# 查看docker是否安装成功

docker --version

# 开机自启动, 好像开机启动并不是很灵

sudo chkconfig docker on

# 查看docker daemon是否在运行

ps aux | grep docker

3设置代理

# following link is to resolve docker-runc not found issue,proxy is not necessary *#

ln -s /usr/libexec/docker/docker-proxy-current /usr/bin/docker-proxy

ln -s /usr/libexec/docker/docker-runc-current /usr/bin/docker-runc

#停止docker service(设置代理前,需要停止)

service docker stop

# 设置代理, 成功后,会自动启动docker service

sudo HTTP_PROXY=http://ip:port /usr/bin/dockerd --userland-proxy=false &

4 Docker Service

# 启动Docker Service

# 注: 设置代理时,Docker Service会自动启动

service docker start

# 或者这种启动方式

systemctl start docker.service

#停止docker service(设置代理前,需要停止)

service docker stop

# 或者这种停止方式

systemctl stop docker.service

# 查看服务状态

systemctl status docker.service

# 查看docker daemon是否在运行

ps aux | grep docker

5 Image

# 下载Image,  默认从docker.io下载,速度会比较慢

#           可以从daocloud.io中下载,速度会快一些.

# 我在公司, Centos上感觉不明显, 在家里用ubuntu感觉特别明显

docker pull centos

# 查询仓库中的Image

# --automated=false:       仅显示自动创建的镜像

# --no-trunc=false:   不截断显示

# -s, --starts=0:        指定星级以上

docker search -s 10 centos

# 查询本地Image

docker images

# 删除Image

docker rmi docker.io/Ubuntu

6 运行Image

# 运行Image

# 注意: 运行Image时, 需要关闭代理,重启docker service,

#      否则会遇到错误:container_linux.go:247: starting container process caused

#      "process_linux.go:334: running prestart hook 1 caused \"error running hook: exit status 1, stdout: , stderr: \""

#          /usr/bin/docker-current: Error response from daemon: invalid header field value "oci runtime error:

#          container_linux.go:247: starting container process caused \"process_linux.go:334:

#           running prestart hook 1 caused \\\"error running hook: exit status 1, stdout: , stderr: \\\"\"\n".

# 方式1

sudo docker  run centos /bin/echo 'Hello World'

# 带调试信息

sudo docker --debug=true run centos /bin/echo 'Hello World'

#方式2

[root@localhost home]# docker create centos

3e8185a9fb586e1b3f12fb1c69c2a22225df1e5505c9315e3b62743d489d2904

# 查看容器信息

[root@localhost home]# docker ps -a

CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES

3e8185a9fb58        centos              "/bin/bash"         5 seconds ago       Created                                 gigantic_franklin

[root@localhost home]# docker start 3e8185a9fb58

docker run -idt --name pcta-demon matthewx:pcta-matthewx

# 进入容器

docker attach pcta-demon

# 删除容器

docker rm 3e8185a9fb58

7 卸载Docker

#centos卸载

yum list installed | grep docker

yum -y remove docker.x86_64

yum -y remove docker-client.x86_64

yum -y remove docker-common.x86_64

# 如果/var/lib/docker删除失败,

# 请使用lsof |grep docker看看有哪些进程在使用,kill掉这些进程.

# 此处删除应该是删除pull的image等,所以也可以不删除.

rm -rf /var/lib/docker

lsof |grep docker