1、初始化
关闭防火墙
systemctl stop firewalld && systemctl disable firewalld
关闭Selinux
vim /etc/sysconfig/selinux 改成disable #需重启生效
关闭swap
swapoff -a
2、升级内核
uname -r #查看当前内核
cat /boot/grub2/grub.cfg |grep menuentry #查看当前内核版本
设置默认系统启动内核
grub2-set-default 'CentOS Linux (4.17.11-1.el7.elrepo.x86_64) 7 (Core)'