查看当前内核版本

 

下载内核地址

https://mirrors.aliyun.com/elrepo/kernel/el7/x86_64/RPMS

安装内核 rpm -ivh kernel-lt-* --nodeps --force

 

awk -F\' '$1=="menuentry " {print $2}' /etc/grub2.cfg    (提示找不到/etc/grub2.cfg  需要重启一下系统)

输出:

0 : CentOS Linux (4.4.222-1.el7.elrepo.x86_64) 7 (Core)
1 : CentOS Linux (3.10.0-1062.el7.x86_64) 7 (Core)
2 : CentOS Linux (0-rescue-beb5a720b4464373968186d773e35ac5) 7 (Core)

重新生成grub配置文件

grub2-mkconfig -o /boot/grub2/grub.cfg
---输出类似如下:
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-5.4.214-1.el7.elrepo.x86_64
Found initrd image: /boot/initramfs-5.4.214-1.el7.elrepo.x86_64.img
Found linux image: /boot/vmlinuz-3.10.0-514.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-514.el7.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-13fa607805964427bb4a2297f3619e6e
Found initrd image: /boot/initramfs-0-rescue-13fa607805964427bb4a2297f3619e6e.img
done

输入grub2-editenv list命令查看默认启动项
grub2-editenv list
saved_entry=CentOS Linux (3.10.0-1062.el7.x86_64) 7 (Core)
输入grub2-set-default命令修改默认启动项 (参照awk -F\' '$1=="menuentry " {print $2}' /etc/grub2.cfg 输出的列表序号 0是4.4.222 1是3.10.0-1062.el7.x86_64)
grub2-set-default 0
再次查看默认启动项,发现默认启动项已经改成了0
[root@bogon ~]# grub2-editenv list
saved_entry=0

重启 reboot
 

 

posted on 2024-01-08 15:27  博客园197  阅读(227)  评论(0编辑  收藏  举报