rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm yum --disablerepo="*" --enablerepo="elrepo-kernel" list available yum --enablerepo=elrepo-kernel install kernel-ml uname -sr reboot
参考文档https://linux.cn/article-8310-1.html
调整内核启动顺序
1，首先查看当前系统有几个内核。比如：
[root@21yunwei ~]# cat /boot/grub2/grub.cfg |grep menuentry
if [ x"${feature_menuentry_id}" = xy ]; then menuentry_id_option="--id" menuentry_id_option="" export menuentry_id_option menuentry 'CentOS Linux (3.10.0-327.22.2.el7.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-327.el7.x86_64-advanced-80b9b662-0a1d-4e84-b07b-c1bf19e72d97' { menuentry 'CentOS Linux (3.10.0-327.el7.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-327.el7.x86_64-advanced-80b9b662-0a1d-4e84-b07b-c1bf19e72d97' { menuentry 'CentOS Linux (0-rescue-7d26c16f128042a684ea474c9e2c240f) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-0-rescue-7d26c16f128042a684ea474c9e2c240f-advanced-80b9b662-0a1d-4e84-b07b-c1bf19e72d97' {
2，设置默认的启动内核。比如我们选择上边中的CentOS Linux (3.10.0-327.el7.x86_64) 7 (Core)这个内核为默认启动。
[root@21yunwei ~]# grub2-set-default "CentOS Linux (3.10.0-327.el7.x86_64) 7 (Core)" 配置默认内核 验证是否修改成功：
[root@21yunwei ~]# grub2-editenv list saved_entry=CentOS Linux (3.10.0-327.el7.x86_64) 7 (Core)
3，重启机器观察。 重启成功以后查看下机器的内核是不是该内核：
[root@21yunwei ~]# uname -r 3.10.0-327.el7.x86_64
