rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm

如果报：curl: (35) Peer reports incompatible or unsupported protocol version.

执行命令： yum update -y nss curl libcurl

2.yum --enablerepo=elrepo-kernel install -y kernel-lt

3.grub2-set-default "Centos Linux (4.4.182-1.e17.elrepo.x86_64) 7 (Core)"

4.重启系统：reboot，查看内核版本：uname -r