檢視核心
uname -a
uname -srm
uname -r 檢視系統版本
cat /etc/os-release 在新主機首次安裝 Docker Engine-Community之前，需要設定Docker倉庫，之後，您可以從倉庫安裝和更新 Docker。
設定倉庫，需要安裝所需的軟體包。yum-utils 提供了 yum-config-manager ，并且 device mapper 存儲驅動程式需要 device-mapper-persistent-data 和 lvm2。
su root
yum install -y yum-utils
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# 檢視yum源
yum repolist
cp CentOS-Base.repo CentOS-Base-repo.bak yum錯誤
File contains no section headers. file: file:///etc/yum.repos.d/CentOS-Base.repo, line: 1 '<!DOCTYPE html>\n' 網絡上的雞肋解決方法
方法1：配置yum源，修改/etc/yum.repos.d/CenOS-Base.repo檔案
方法2：删除原檔案重新下載下傳
删除原有的檔案 rm -f /etc/yum.repos.d/CentOS-Base.repo
重新下載下傳，wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
清理緩存 yum clean all 實際問題，wget下載下傳的檔案格式不對，手動下載下傳然後傳到伺服器中即可
rm -f /etc/yum.repos.d/CentOS-Base.repo
下載下傳http://mirrors.aliyun.com/repo/Centos-7.repo
xftp以管理者打開，上傳到/etc/yum.repos.d
yum clean all
yum update xftp無權限
window以管理者運作
yum無法update和makcache
使用了橋接模式
可以ping通
無法yum update
更改網絡擴充卡為NAT,橋接模式需要上網任務，同程管家，，，fk！！
改為NAT後，重新開機虛拟機，yum makcache搞定 - 1、首先備份 CentOS-Base.repo
sudo mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak - 2.将yum源配置檔案/etc/yum.repos.d/CentOS-Base.repo改為清華源,内容如下:
> [base]
> name=CentOS-$releasever - Base
> baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/os/$basearch/
> #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
> gpgcheck=1
> gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
>
> #released updates
> [updates]
> name=CentOS-$releasever - Updates
> baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/updates/$basearch/
> #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
> gpgcheck=1
> gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
>
> #additional packages that may be useful
> [extras]
> name=CentOS-$releasever - Extras
> baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/extras/$basearch/
> #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
> gpgcheck=1
> gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
>
> #additional packages that extend functionality of existing packages
> [centosplus]
> name=CentOS-$releasever - Plus
> baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/centosplus/$basearch/
> #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus
> gpgcheck=1
> enabled=0
> gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7 - 3、清除緩存
yum clean all
rm -rf /var/cache/yum/ - 4、生成緩存
yum makecache ![linux-svn解除安裝與安裝[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)