前提條件
Docker運行對內核要求比較高，因此一般建議直接在Ubuntu這樣的平台運行。但作為一個容器標准，Docker也是支持其他如CentOS, Mac OS X, Windows等平台。目前Docker支持以下版本CentOS:
- CentOS 7(64位)
- CentOS 6.5(64位)及以后
在運行CentOS 6.5及以后版本時，需要內核版本>=2.6.32-431，因為這些內核包含了運行Docker的一些特定修改。
$ uname -r
2.6.32-431.17.1.el6.x86_64
Device Mapper
Docker默認使用AUFS作為存儲驅動，但是AUFS並沒有被包括在Linux的主線內核中。CentOS中可以使用Device Mapper作為存儲驅動，這是在2.6.9內核版本引入的新功能。我們需要先確認是否啟用該功能:
$ ls -l /sys/class/misc/device-mapper
lrwxrwxrwx 1 root root 0 May 1 20:55 /sys/class/misc/device-mapper -> ../../devices/virtual/misc/device-mapper
如果沒有檢測到Device Mapper，需要安裝device-mapper軟件包:
$ yum install -y device-mapper
然后重新加載dm_mod內核模塊:
$ modprobe dm_mod
對於centos 6.5 需要先安裝源
$ rpm -Uvh http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm
$ yum install docker-io -y
提示無法安裝
查閱資料，yum install docker-io,這句話是用源安裝docker,可是源一般是國外源，用這個命令因為GFW被牆，根本安裝不了。開源中國Docker更新記錄
Ubuntu/Debian: curl -sSL https://get.docker.com | sh
Linux 64bit binary: https://get.docker.com/builds/Linux/x86_64/docker-1.7.1
Darwin/OSX 64bit client binary: https://get.docker.com/builds/Darwin/x86_64/docker-1.7.1
Darwin/OSX 32bit client binary: https://get.docker.com/builds/Darwin/i386/docker-1.7.1
Linux 64bit tgz: https://get.docker.com/builds/Linux/x86_64/docker-1.7.1.tgz
Windows 64bit client binary: https://get.docker.com/builds/Windows/x86_64/docker-1.7.1.exe
Windows 32bit client binary: https://get.docker.com/builds/Windows/i386/docker-1.7.1.exe
Centos 6/RHEL 6: https://get.docker.com/rpm/1.7.1/centos-6/RPMS/x86_64/docker-engine-1.7.1-1.el6.x86_64.rpm
Centos 7/RHEL 7: https://get.docker.com/rpm/1.7.1/centos-7/RPMS/x86_64/docker-engine-1.7.1-1.el7.centos.x86_64.rpm
Fedora 20: https://get.docker.com/rpm/1.7.1/fedora-20/RPMS/x86_64/docker-engine-1.7.1-1.fc20.x86_64.rpm
Fedora 21: https://get.docker.com/rpm/1.7.1/fedora-21/RPMS/x86_64/docker-engine-1.7.1-1.fc21.x86_64.rpm
Fedora 22: https://get.docker.com/rpm/1.7.1/fedora-22/RPMS/x86_64/docker-engine-1.7.1-1.fc22.x86_64.rpm
使用Centos 6/RHEL 6，開始安裝
yum install https://get.docker.com/rpm/1.7.1/centos-6/RPMS/x86_64/docker-engine-1.7.1-1.el6.x86_64.rpm
啟動Docker
service docker start
查看Docker信息
docker info
設置開機啟動
chkconfig docker on