Centos6.7安装docker1.7.1

　　Docker当前发布的最新版本已经到了1.11，其官网上针对Centos的的安装需求如下:

Docker requires a -bit installation regardless of your CentOS version. Also, your kernel must be 3.10 at minimum, which CentOS  runs.

看来如果我们想在低于3.x内核的操作系统（比如Centos6.7）上装Docker最新版，势必要升级内核了。且不说升级内核步骤繁琐、容易出错，单就这种比较怪异的搭配：Centos6.x + Kerneol3.X + Docker1.11，就没有人能够保证其稳定性。故我的建议是设法在Centos6.7上安装较低版本的Docker。事实上，对于内核版本要大于3.10这个要求，是从Docker1.8.2版本开始的，Docker之前的版本是可以运行在较低内核版本之上的，比如1.7.1。

　　

　　首先，看下我的操作环境以及直接安装Docker的现象：

[root@localhost ~]# uname -a
Linux localhost.localdomain 2.6.-.el6.x86_64 # SMP Thu Jul  :: UTC  x86_64 x86_64 x86_64 GNU/Linux
[root@localhost ~]# cat /etc/redhat-release
CentOS release 6.7 (Final)
[root@localhost ~]# docker
-bash: docker: command not found
[root@localhost ~]# yum install docker
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Install Process
base                                  | 3.7 kB     :
base/primary_db                       | 4.6 MB     :
extras                                | 3.4 kB     :
extras/primary_db                     |   kB     :
updates                               | 3.4 kB     :
updates/primary_db                    | 5.2 MB     :
No package docker available.
Error: Nothing to do
[root@localhost ~]# yum install docker-io
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Install Process
Determining fastest mirrors
 * base: mirrors.zju.edu.cn
 * extras: mirrors.skyshe.cn
 * updates: mirrors.zju.edu.cn
No package docker-io available.
Error: Nothing to do

可以看到，在Centos6.7的标准yum源中已经没有Docker的安装包了，这时，我们需要安装EPEL。

　　EPEL（Extra Packages for Enterprise Linux），企业版Linux额外包，RHEL分布非标准包的社区类库。安装如下：

[root@localhost ~]# rpm -iUvh http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
Retrieving http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
warning: /var/tmp/rpm-tmp.sA7VqQ: Header V3 RSA/SHA256 Signature, key ID 0608b895: NOKEY
Preparing...                ########################################### [%]
   :epel-release           ########################################### [%]

　　

　　接下来安装Docker1.7.1，在1.7.1中，安装包名称为docker-io，故我们的安装命令如下：

[root@localhost ~]# yum install docker-io
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Install Process
Loading mirror speeds from cached hostfile
epel/metalink                                                           | 5.3 kB     :
 * base: mirrors.zju.edu.cn
 * epel: ftp.cuhk.edu.hk
 * extras: mirrors.skyshe.cn
 * updates: mirrors.zju.edu.cn
epel                                                                    | 4.3 kB     :
epel/primary_db                                                         | 5.9 MB     :
Resolving Dependencies
--> Running transaction check
---> Package docker-io.x86_64 :1.7.-.el6 will be installed
--> Processing Dependency: lxc for package: docker-io-1.7.-.el6.x86_64
--> Processing Dependency: libcgroup for package: docker-io-1.7.-.el6.x86_64
--> Running transaction check
---> Package libcgroup.x86_64 :0.40.rc1-.el6_7 will be installed
---> Package lxc.x86_64 :1.0.-.el6 will be installed
--> Processing Dependency: lua-lxc(x86-) = 1.0.-.el6 for package: lxc-1.0.-.el6.x86_64
--> Processing Dependency: lua-alt-getopt for package: lxc-1.0.-.el6.x86_64
--> Processing Dependency: liblxc.so.()(64bit) for package: lxc-1.0.-.el6.x86_64
--> Running transaction check
---> Package lua-alt-getopt.noarch :0.7.-.el6 will be installed
---> Package lua-lxc.x86_64 :1.0.-.el6 will be installed
--> Processing Dependency: lua-filesystem for package: lua-lxc-1.0.-.el6.x86_64
---> Package lxc-libs.x86_64 :1.0.-.el6 will be installed
--> Running transaction check
---> Package lua-filesystem.x86_64 :1.4.-.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

===================================================================================
 Package               Arch            Version             Repository    Size
===================================================================================
Installing:
 docker-io             x86_64          1.7.-.el6         epel          4.6 M
Installing for dependencies:
 libcgroup             x86_64          0.40.rc1-.el6_7   updates        k
 lua-alt-getopt        noarch          0.7.-.el6         epel          6.9 k
 lua-filesystem        x86_64          1.4.-.el6         epel           k
 lua-lxc               x86_64          1.0.-.el6         epel           k
 lxc                   x86_64          1.0.-.el6         epel           k
 lxc-libs              x86_64          1.0.-.el6         epel           k

Transaction Summary
====================================================================================
Install        Package(s)

Total download size: 5.1 M
Installed size:  M
Is this ok [y/N]: y
Downloading Packages:
(/): docker-io-1.7.-.el6.x86_64.rpm                                   | 4.6 MB     :
(/): libcgroup-0.40.rc1-.el6_7.x86_64.rpm                             |  kB     :
(/): lua-alt-getopt-0.7.-.el6.noarch.rpm                              | 6.9 kB     :
(/): lua-filesystem-1.4.-.el6.x86_64.rpm                              |   kB     :
(/): lua-lxc-1.0.-.el6.x86_64.rpm                                     |   kB     :
(/): lxc-1.0.-.el6.x86_64.rpm                                         |  kB     :
(/): lxc-libs-1.0.-.el6.x86_64.rpm                                    |  kB     :
----------------------------------------------------------------------------------------------
Total                                                           kB/s | 5.1 MB     :
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID 0608b895: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
Importing GPG key 0x0608B895:
 Userid : EPEL () <epel@fedoraproject.org>
 Package: epel-release--.noarch (installed)
 From   : /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-
Is this ok [y/N]: y
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA1 Signature, key ID c105b9de: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
Importing GPG key 0xC105B9DE:
 Userid : CentOS- Key (CentOS  Official Signing Key) <centos--key@centos.org>
 Package: centos-release--.el6.centos.12.3.x86_64 (@anaconda-CentOS-.x86_64/6.7)
 From   : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-
Is this ok [y/N]: y
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Warning: RPMDB altered outside of yum.
  Installing : lxc-libs-1.0.-.el6.x86_64                                              /
  Installing : lua-filesystem-1.4.-.el6.x86_64                                        /
  Installing : lua-lxc-1.0.-.el6.x86_64                                               /
  Installing : lua-alt-getopt-0.7.-.el6.noarch                                        /
  Installing : lxc-1.0.-.el6.x86_64                                                   /
  Installing : libcgroup-0.40.rc1-.el6_7.x86_64                                       /
  Installing : docker-io-1.7.-.el6.x86_64                                             /
  Verifying  : lxc-libs-1.0.-.el6.x86_64                                              /
  Verifying  : libcgroup-0.40.rc1-.el6_7.x86_64                                       /
  Verifying  : lua-lxc-1.0.-.el6.x86_64                                               /
  Verifying  : lxc-1.0.-.el6.x86_64                                                   /
  Verifying  : docker-io-1.7.-.el6.x86_64                                             /
  Verifying  : lua-alt-getopt-0.7.-.el6.noarch                                        /
  Verifying  : lua-filesystem-1.4.-.el6.x86_64                                        / 

Installed:
  docker-io.x86_64 :1.7.-.el6

Dependency Installed:
  libcgroup.x86_64 :0.40.rc1-.el6_7
  lua-alt-getopt.noarch :0.7.-.el6
  lua-filesystem.x86_64 :1.4.-.el6
  lua-lxc.x86_64 :1.0.-.el6
  lxc.x86_64 :1.0.-.el6
  lxc-libs.x86_64 :1.0.-.el6 

Complete!
[root@localhost ~]# docker -v
Docker version 1.7., build 786b29d/1.7.

安装完成！