I have recently added Debian Jessie/XFCE to my laptop, which already had Mint 17.1 and Puppy Slacko 5.7 on it, the Puppy being a frugal install. I let Puppy look after the booting, because Grub2 does not recognise frugal installs, so the menu file has to be manually created, using section 40-custom.
Anyway, neither Puppy grub4dos, nor Mint Grub2, can see the Debian /boot/initrd<etc> file by way of the symlink from the base directory. Puppy constructs a menu file without the initrd line, whereas Mint (using Grub2) misses Debian out altogether, presumably it thinks that no entry is better than a partial one!
The problem is that the symlink is (I think) an absolute one, pointing to /boot/initrd.img<version>. It seems that it needs to be a relative symlink.
If I delete the original symlink, and create a new one:
ln -s boot/initrd.img<version>
then the other distros can boot Debian ok. Do you see the difference? The present symlink has /boot/..., the one that works has boot/, ie no leading /.
So changing the symlink will allow the other distros to be in charge of booting- but only until a Debian update changes the initrd.img version number, and puts back the leading /. Then the symlink needs to be changed again.
So I gave in, and edited the grub.d custom file in Debian to include Puppy. So now Debian has made sure that it is top of the list when I boot.... is this all a deliberate plot?
Edit: afterthought- the similar vmlinuz symlink works. The difference is that the vmlinuz symlink points to a file, the initrd symlink points to a disc image. Anyone know why this matters?
Edit: oops, I need to change my signature, I'm 79 now.
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