Bootloader entry for another Grub2

Hello. Without too much explanation, I have installed Windows on sda, fedora with LVM on sdb and Fedora’s /boot on sdb2.
When I installed openSUSE, GRUB2 sees openSUSE and windows, but not fedora (I had opensuse before this installation, on the very same partition on sdb). Currently, bootloader is in mbr, or at least it should be sinec I tinkered with it and may have moved opensuse to boot from root.

Either way, how can I redirect grub2 to look for Fedora’s /boot partition, which itself it seems contains a grub2 loader. OSProber doesn’t work, checking custom boot partition in Yast’s bootloader doesn’t either.
I’d like to evade reinstalling fedora with / on a non LVM partition and setting it up to boot from there (os prober should find it then, right?)

Thanks.

And your openSUSE version is … ?

Currently installing, so it’s kind of safe to assume => 12.3
And Fed18

openSUSE 12.3 os-prober is expected to find Fedora 18 (at least, it did for me). What is output of “os-prober”?

You can another grub2 using “multiboot” grub2 command, i.e. “multiboot (hd0,3)/grub/i386-pc/core.img”. But I would prefer to find out why os-prober did not work.

I did that the other way. I had opensuse on an encrypted LVM, and Fedora 18 installed to an ext4 partition.

For me, it was the grub2 menu for Fedora that did not pickup an entry for opensuse.

To fix it, you need to make the LVM accessible.

In my case, I had to run:


# cryptsetup luksOpen device virtual-name

and then:


# lvm vgchange -a y

before running “grub2-mkconfig”.

In your case, if the LVM is not encrypted, you probably only need:


# vgchange -a y

and then, running “grub2-mkconfig” should add the entry you want.

I find it useful to add a few lines to “/etc/grub.d/40_custom”


menuentry "configfile for grub/linux on /dev/sda6" {
       configfile (hd0,6)/boot/grub2/grub.cfg
}

which gives me an alternate way of accessing the grub configuration for the other system.