2020年11月30日 CentOS 6 已经不支持继续使用了，目前第三方的镜像中均已移除 CentOS 6 的源。阿里云的源和清华的源都已经无法同步到 CentOS 6 的源。
在使用 yum install gcc-c++ 命令安装时，会直接提示报错
解决方法，修改 /etc/yum.repos.d/CentOS-Base.repo，修改结果如下：
# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client. You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the
# remarked out baseurl= line instead.
[base]
name=CentOS-6.10
enabled=1
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos-vault/6.10/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-6
[updates]
name=CentOS-6.10
enabled=1
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos-vault/6.10/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.comm/centos-vault/RPM-GPG-KEY-CentOS-6
[extras]
name=CentOS-6.10
enabled=1
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos-vault/6.10/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-6
- 然后使用命令，清除缓存
yum clean all
yum makecache
如下所示：
清除缓存.jpg
-
然后就可以安装 gcc-c++
下载安装 gcc .jpg - 安装完成之后就可以使用 make 命令继续安装 Redis。
