Ladies and Gentlemen!
(First, I have to excuse because I posted this question on another site of openSuse some ten minutes ago (which I don’t find anymore). I’ve not been here for a long time.)
I tried to install Leap 42.2 (on a dual-boot system with Win7).
Currently there is 13.2 installed, but support ended, so I need to change.
The installation-Preparation procedure on (downloaded) DVD results in suggesting the installation of GRUB2 und /dev/sda6 which is a logical partition and will not work, i.e. will result in a not-bootable system. (I had the same problem when installing 13.2 and needed long time and effort to find a solution.)
I know what is necessary:
Installation of GRUB (whatever version) on /dev/sda4 and setting the bootflag on /dev/sda4 (i.e. the base of the extended partition - as it is now).
(I don’t want to install GRUB in MBR, because this will be overwritten by Win10, if ever I intend to …)
However, I didn’t find a menu/branch in the installation-preparation routine to select type and location of GRUB.
It will not work with Windows MBR. It will work with Syslinux MBR that is installed by openSUSE when you select “Write generic MBR”. As some reports indicate, Windows “accepts” this MBR code and does not try to rewrite it (YMMV).
To change bootloader location on summary screen click Bootloader.
As arvidjaar suggest, it should work fine booting from “/dev/sda6”. But make sure that the box is checked, to install generic boot code into the MBR. The boot code that will be installed can boot logical partitions.
If Windows ever overwrites the MBR, it is very easy to re-install that boot code. You could boot from rescue media, mount your boot partition, and write that generic boot code back into the MBR. (Ask if you want more details).
However, I would suggest another option. With linux booting from sda6, you could also add an entry to boot it with the Windows boot manager. You can easily find how with google. And then, if Windows overwrites the MBR, booting via the Windows boot manager will still work.
Thank you for all advice & hints.
I’m doing this type of work not even once a year. So, I wanted to avoid changes.
Finally, I found that I simply should have proceeded till to the last page of the installation-preparation menu (the one before the installation really starts) which allows to check and change all the boot-process settings:
GRUB2 from extended partition.
Active-/Boot-flag on extended partiction. (/dev/sda4)