我在使用 CentOS 6 系统时遇到了一个奇怪的问题。
我已经升级了两次内核，但当我重启系统时，它仍然加载旧内核。我还让一名 dc 技术人员在重启时观察屏幕，他们也感到困惑，但没能发现任何问题。
当前内核：
[root@srv99 ~]# uname -r
2.6.32-220.el6.x86_64
当前 grub 配置：
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (2.6.32-358.2.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-358.2.1.el6.x86_64 ro root=/dev/mapper/vg_srv99-lv_root rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_LVM_LV=vg_srv99/lv_root rd_LVM_LV=vg_srv99/lv_swap quiet rd_NO_MD rhgb crashkernel=auto rd$
initrd /initramfs-2.6.32-358.2.1.el6.x86_64.img
title CentOS (2.6.32-279.19.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-279.19.1.el6.x86_64 ro root=/dev/mapper/vg_srv99-lv_root rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_LVM_LV=vg_srv99/lv_root rd_LVM_LV=vg_srv99/lv_swap quiet rd_NO_MD rhgb crashkernel=auto r$
initrd /initramfs-2.6.32-279.19.1.el6.x86_64.img
title CentOS (2.6.32-279.14.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-279.14.1.el6.x86_64 ro root=/dev/mapper/vg_srv99-lv_root rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_LVM_LV=vg_srv99/lv_root rd_LVM_LV=vg_srv99/lv_swap quiet rd_NO_MD rhgb crashkernel=auto r$
initrd /initramfs-2.6.32-279.14.1.el6.x86_64.img
title CentOS (2.6.32-220.13.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-220.13.1.el6.x86_64 ro root=/dev/mapper/vg_srv99-lv_root rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_LVM_LV=vg_srv99/lv_root rd_LVM_LV=vg_srv99/lv_swap quiet rd_NO_MD rhgb crashkernel=auto r$
initrd /initramfs-2.6.32-220.13.1.el6.x86_64.img
title CentOS (2.6.32-220.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-220.el6.x86_64 ro root=/dev/mapper/vg_srv99-lv_root rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_LVM_LV=vg_srv99/lv_root rd_LVM_LV=vg_srv99/lv_swap quiet rd_NO_MD rhgb crashkernel=auto rd_DM_$
initrd /initramfs-2.6.32-220.el6.x86_64.img
/boot/grub 的内容
[root@srv99 ~]# ls -l /boot/grub
total 274
-rw-r--r--. 1 root root 120 May 2 2012 device.map
-rw-r--r--. 1 root root 13380 May 2 2012 e2fs_stage1_5
-rw-r--r--. 1 root root 12620 May 2 2012 fat_stage1_5
-rw-r--r--. 1 root root 11748 May 2 2012 ffs_stage1_5
-rw------- 1 root root 2626 Apr 8 13:23 grub.conf
-rw-r--r--. 1 root root 11756 May 2 2012 iso9660_stage1_5
-rw-r--r--. 1 root root 13268 May 2 2012 jfs_stage1_5
lrwxrwxrwx. 1 root root 11 May 2 2012 menu.lst -> ./grub.conf
-rw-r--r--. 1 root root 11956 May 2 2012 minix_stage1_5
-rw-r--r--. 1 root root 14412 May 2 2012 reiserfs_stage1_5
-rw-r--r-- 1 root root 1341 Nov 14 2010 splash.xpm.gz
-rw-r--r--. 1 root root 512 May 2 2012 stage1
-rw-r--r--. 1 root root 125976 Jan 3 06:48 stage2
-rw-r--r--. 1 root root 12024 May 2 2012 ufs2_stage1_5
-rw-r--r--. 1 root root 11364 May 2 2012 vstafs_stage1_5
-rw-r--r--. 1 root root 13964 May 2 2012 xfs_stage1_5