現象：服務器可以正常上網，且yum源文件配置是准確無誤的
報錯信息如下：
[root@localhost ~]# yum list Loaded plugins: fastestmirror https://mirrors.aliyun.com/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#60 - "Peer's Certificate has expired." Trying other mirror. It was impossible to connect to the CentOS servers. This could mean a connectivity issue in your environment, such as the requirement to configure a proxy, or a transparent proxy that tampers with TLS security, or an incorrect system clock. Please collect information about the specific failure that occurs in your environment, using the instructions in: https://access.redhat.com/solutions/1527033 and create a bug on https://bugs.centos.org/ One of the configured repositories failed (centos), 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. Disable the repository, 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 centos 4. 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=centos.skip_if_unavailable=true failure: repodata/repomd.xml from centos: [Errno 256] No more mirrors to try. https://mirrors.aliyun.com/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#60 - "Peer's Certificate has expired."
解決辦法：
可能是由於服務器時間不正確導致https證書認證錯誤
更新服務器時間即可
例:
date -s “2018-11-18 12:00:00”
或者
ntpdate 0.asia.pool.ntp.org
參考網站：
https://cloud.tencent.com/developer/article/1372484