Since using grub 2 I am puzzled by the way the boot menu is created. I usually have some extra installations on different disks or partitions. When doing a os-prober and grub-update my menu will contain all combinations of all systems and all kernels. I think I understand, that this is, because the system cannot know which kernel belongs to which system. And probably it is not a ood idea to put all the kernels into the boot partition. But, that is not actually my decision. I am mainly using ubuntu, but I would like to get a understanding, how I should create a multiboot environment properly in the general case. Assuming, that grub 2 is involved.