我在执行脚本的时候，报错如下：
Loaded plugins: fastestmirror, langpacks, update-motd
Loading mirror speeds from cached hostfile
- base: mirrors.cloud.aliyuncs.com
- extras: mirrors.cloud.aliyuncs.com
- updates: mirrors.cloud.aliyuncs.com
http://mirrors.cloud.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
Trying other mirror.
http://mirrors.aliyun.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
Trying other mirror.
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30001 milliseconds')
Trying other mirror.
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30001 milliseconds')
Trying other mirror.
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30001 milliseconds')
Trying other mirror.
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30000 milliseconds')
Trying other mirror.
^Chttp://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 14] curl#56 - "Callback aborted"
Trying other mirror.One of the configured repositories failed (CentOS-2.1903 - Base - mirrors.aliyun.com),
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=base ... 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 base or subscription-manager repos --disable=base 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=base.skip_if_unavailable=truefailure: repodata/repomd.xml from base: [Errno 256] No more mirrors to try.
http://mirrors.cloud.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
http://mirrors.aliyun.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30001 milliseconds')
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30001 milliseconds')
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30001 milliseconds')
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 12] Timeout on http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: (28, 'Connection timed out after 30000 milliseconds')
http://mirrors.aliyuncs.com/centos/2.1903/os/x86_64/repodata/repomd.xml: [Errno 14] curl#56 - "Callback aborted"
解决方法如下：
将
CentOS-Base.repo文件中所有$releasever替换成7就好了
1、编辑 CentOS-Base.repo 文件
vim /etc/yum.repos.d/CentOS-Base.repo
2、输入冒号 : ，继续输入 %s/$releasever/7/g，按回车键替换
:%s/$releasever/7/g
3、再次输入冒号 :，继续输入 wq， 按回车键退出并保存
:wq
4、替换后的文件内容如下：
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
#additional packages that may be useful
[extras]
name=CentOS-7 - Extras - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/7/extras/$basearch/
http://mirrors.aliyuncs.com/centos/7/extras/$basearch/
http://mirrors.cloud.aliyuncs.com/centos/7/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-7 - Plus - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/7/centosplus/$basearch/
http://mirrors.aliyuncs.com/centos/7/centosplus/$basearch/
http://mirrors.cloud.aliyuncs.com/centos/7/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
#contrib - packages by Centos Users
[contrib]
name=CentOS-7 - Contrib - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/7/contrib/$basearch/
http://mirrors.aliyuncs.com/centos/7/contrib/$basearch/
http://mirrors.cloud.aliyuncs.com/centos/7/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
