如何在grub里边添加 以前的cent引导？

[Polarex]

装了ubuntu之后原来的cent 进不去了，使用update-grub显示
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-3.2.0-60-generic
Found initrd image: /boot/initrd.img-3.2.0-60-generic
Found linux image: /boot/vmlinuz-3.2.0-24-generic
Found initrd image: /boot/initrd.img-3.2.0-24-generic
Found memtest86+ image: /boot/memtest86+.bin
Found Windows Vista (loader) on /dev/sda1
Found Windows Recovery Environment (loader) on /dev/sda3
Found Windows 8 (loader) on /dev/sda5
Found CentOS release 6.5 (Final) on /dev/sdb3
done
能找到 但是不能自动添加吗？

[gxustudent]

手动修改/boot/grub/grub.cfg文件，参照原来ubuntu的修改。