#升级内核
rpm –import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
#Centos7启用该源仓库
rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
#查看有哪些内核版本可供安装
yum –disablerepo=”*” –enablerepo=”elrepo-kernel” list available
#安装的长期稳定版本lt(推荐，！！！不要安装不稳定版本)
yum –enablerepo=elrepo-kernel install kernel-lt -y
#解决无法启动问题
#vi /etc/default/grub
#GRUB_CMDLINE_LINUX=”crashkernel=auto spectre_v2=retpoline rd.lvm.lv=centos/root rd.lvm.lv=centos/swap rhgb quiet mgag200.modeset=0”
sed -i ‘s#GRUB_CMDLINE_LINUX=”crashkernel=auto spectre_v2=retpoline rhgb quiet”#GRUB_CMDLINE_LINUX=”crashkernel=auto spectre_v2=retpoline rd.lvm.lv=centos/root rd.lvm.lv=centos/swap rhgb quiet mgag200.modeset=0”#g’ /etc/default/grub
#退出重新生成grub
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg
#查看启动顺序
awk -F' ‘$1==”menuentry “ {print i++ “ : “ $2}’ /boot/efi/EFI/centos/grub.cfg
#调整默认启动内核
grub2-set-default “CentOS Linux (5.4.113-1.el7.elrepo.x86_64) 7 (Core)”
#查看当前默认启动内核
grub2-editenv list
#重启
#reboot
检查当前启动的内核版本：
uname -rs