使用yun install cmake3 安装 ，不会覆盖centos7 cmake
1 添加cmake3 源
echo '[group_kdesig-cmake3_EPEL]
name=Copr repo for cmake3_EPEL owned by @kdesig
baseurl=https://copr-be.cloud.fedoraproject.org/results/@kdesig/cmake3_EPEL/epel-7-$basearch/
type=rpm-md
skip_if_unavailable=True
gpgcheck=1
gpgkey=https://copr-be.cloud.fedoraproject.org/results/@kdesig/cmake3_EPEL/pubkey.gpg
repo_gpgcheck=0
enabled=1
enabled_metadata=1' >> /etc/yum.repos.d/cmake3.repo
2执行命令安装 yum install -y cmake3
可能需要安装 yum install jsoncpp
注：http://download-ib01.fedoraproject.org/pub/epel/7/x86_64/Packages/ 通过这链接下载对应rpa 源 ，后使用 localinstall