hi
i have windows 8 and suse 12.3 in my grub2 efi menu.
windows 8 don’t really support some power saving battery mode so i will need to come back to windows 7 for this.
when i will finish to install windows 7, is there any command to run to grub2 to allow to add this new entry?
thanks
So you indicate you are using grub-efi is that correct? Normally you use that to boot from a GPT formatted hard disk. Grub 2 seems able to select from different openSUSE kernel versions, but to boot Windows, also from the same GPT disk requires that you change the selection in your UEFI enabled PC setup to switch. When you mention Windows 7, I wonder if you are thinking it will also boot from a GPT or what you are really trying to do? Here is some info on hard disk partitions: Creating Partitions During Install for MBR and GPT Hard Disks - Blogs - openSUSE Forums and I have a nice bash script that works with grub 2 you can find here: GNU Grub2 Command Listing Helper with --help & Input - Blogs - openSUSE Forums . For MBR disks, you are free to do anything you want. GPT formatted disks, which supports disks larger that 2.2 Terabytes and booting Windows 8 in secure boot mode, will become much more common to see. Once a single hard disk is setup as GPT, you just about have to wipe it out and start over to switch to a MBR setup. There are exceptions, but not a lot choices for working with Windows and openSUSE on a GPT disk. If you indeed have a working grub 2 setup with Windows 8 and openSUSE on GPT, I would very hesitant to take it all down and try to install Windows 7.
Thank You,
On EFI only entry for Windows bootloader on ESP is added to grub2 menu, not to individual Windows installations. When you install additional Windows system I expect it adds entries to this bootloader, so nothing needs to be done. Which of two Windows installations will be booted by default is controlled by Windows loader either, grub2 does not know how to control it.
BTW on EFI grub2 menu entry should be named “Windows Boot Manager”. If you really have entry named “Windows 8” you probably do not use EFI in the first place.