容器是近年来一热词，其以轻量，快速面著称。它是一种虚拟化机制，最小单位到进程级别，以进程进行分隔。Docker技术主要包括三大块：镜像；容器和仓库。下文是在Centos上实现Docker的一些技术搞要。

1. 内核3.8+ CentOS7.x
    yum install epel-release docker -y
2. CentOS 6.x
    yum install epel-release -y
    yum install device-map* -y
    yum install docker-io    -y 
    rpm -qa | grep -e "docker" "device" 
3.启动DOCKER
    systemctl restart docker.service 
    systemctl start docker
    service start docker
    ps -ef docker
    docker  info | more
    
    docker
    docker image
    docker search nginx
    docker pull docker.io/nginx
    
    docker run -itd docker.io/nginx
    docker run -itd -p 80:80 docker.io/nginx
    docker ps
    docker ps -a
    docker start ID
    
    docker insepct idxxx | grep -i ip
    wget 172.17.0.100
    
    docker exec it ID /bin/bash
    cat xxx | docker -import centos