1.卸載docker舊版本：

sudo yum remove docker \
? ? ? ? ? ? ? ? ? docker-client \
? ? ? ? ? ? ? ? ? docker-client-latest \
? ? ? ? ? ? ? ? ? docker-common \
? ? ? ? ? ? ? ? ? docker-latest \
? ? ? ? ? ? ? ? ? docker-latest-logrotate \
? ? ? ? ? ? ? ? ? docker-logrotate \

2.安裝相關工具類：

sudo yum install -y yum-utils \ device-mapper-persistent-data \ lvm2

3.配置docker倉庫：

sudo yum-config-manager \ --add-repo \ https://download.docker.com/linux/centos/docker-ce.repo

會報以下錯誤： Loaded plugins: fastestmirror adding repo from: https://download.docker.com/linux/centos/docker-ce.repo grabbing file https://download.docker.com/linux/centos/docker-ce.repo to /etc/yum.repos.d/docker-ce.repo Could not fetch/save url https://download.docker.com/linux/centos/docker-ce.repo to file /etc/yum.repos.d/docker-ce.repo : [Errno 14] curl#35 - "TCP connection reset by peer

這是由於國內訪問不到docker官方鏡像的緣故?
可以通過aliyun的源來完成：

sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

出現以下內容則表示docker倉庫配置成功：

Loaded plugins: fastestmirror adding repo from: http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo grabbing file http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo to /etc/yum.repos.d/docker-ce.repo repo saved to /etc/yum.repos.d/docker-ce.repo

4.安裝docker

sudo yum install docker-ce

出現以下異常：
Loaded plugins: fastestmirror
base
https://download-stage.docker.com/linux/centos/7/x86_64/stable/repodata/repomd.xml: [Errno 14] curl#35 - "TCP connection reset by peer"
Trying other mirror.
?One of the configured repositories failed (Docker CE Stable - x86_64),
?and yum doesn‘t have enough cached data to continue. At this point the only
?safe thing yum can do is fail. There are a few ways to work "fix" this:

? ? ?1. Contact the upstream for the repository and get them to fix the problem.

? ? ?2. Reconfigure the baseurl/etc. for the repository, to point to a working
? ? ? ? upstream. This is most often useful if you are using a newer
? ? ? ? distribution release than is supported by the repository (and the
? ? ? ? packages for the previous distribution release still work).

? ? ?3. Run the command with the repository temporarily disabled
? ? ? ? ? ? yum --disablerepo=docker-ce-stable ...

? ? ?4. Disable the repository permanently, so yum won‘t use it by default. Yum
? ? ? ? will then just ignore the repository until you permanently enable it
? ? ? ? again or use --enablerepo for temporary usage:

? ? ? ? ? ? yum-config-manager --disable docker-ce-stable
? ? ? ? or
? ? ? ? ? ? subscription-manager repos --disable=docker-ce-stable

? ? ?5. Configure the failing repository to be skipped, if it is unavailable.
? ? ? ? Note that yum will try to contact the repo. when it runs most commands,
? ? ? ? so will have to try and fail each time (and thus. yum will be be much
? ? ? ? slower). If it is a very temporary problem though, this is often a nice
? ? ? ? compromise:

? ? ? ? ? ? yum-config-manager --save --setopt=docker-ce-stable.skip_if_unavailable=true

failure: repodata/repomd.xml from docker-ce-stable: [Errno 256] No more mirrors to try.
https://download-stage.docker.com/linux/centos/7/x86_64/stable/repodata/repomd.xml: [Errno 14] curl#35 - "TCP connection reset by peer"

[root@localhost yum.repos.d]# systemctl restart docker?
[root@localhost yum.repos.d]# systemctl status docker

解決Centos7安裝docker源問題