Originally Posted by centguy
Somehow I believe the partition where FC9 resides can't be mounted or something that causes
Error 2: bad file or directory.
I believe you're right about that. Your scenario and that error message immediately reminded me of the incident that arose last summer regarding the 256-byte inodes in the Fedora 9 file system. It was commonly reported for a while during the month of June.
Fedora 9 was the first Fedora version to introduce the 256-byte inode file system in preparation for the coming ext4 file system. Last summer, not long after Fedora 9's release, people discovered that they sometimes could not boot Fedora 9
with the GRUB boot loader of previous versions of Fedora or some other Linux systems. Anyway, it was all related to the grub package and the GRUB boot loader it installs in the older Linux systems. It could not access files in these new 256-inode file systems. Eventually, the grub package was patched for this issue with v0.97-21. Actually that happened way earlier in January, but a patched version (v0.97-33) didn't make into the Fedora repos until June. But that is the true story about GRUB and the new 256-byte inodes and the trouble it caused last summer. And it sounds a lot like your story.
What you did was move the kernel and intial ramdisk files to a partition formatted by (and therefore readable by) CentOS and it worked. Good idea. When typing this, I just read where you were able to use the chainloader command in the CentOS grub.conf to boot F9. That works because the chainloader command does not try to access any file in the Fedora 9 file system. It merely loads and executes the boot sector code of its boot partition.
Anyway, if your CentOS grub package is earlier than v0.97-21, then another method of dealing with this is issue to update CentOS's grub package. But after that, you still have to do one more thing for it to make any difference booting F9. You must then use that new grub package to re-install CentOS's GRUB boot loader. Then CentOS will be able to boot everything again by any method (direct, chainloader, configfile).
P.S.: If you decide not to update CentOS's grub package and re-install its GRUB boot loader, that's perfectly okay. That chainloader command is an aceptable way of dealing with this. In fact, a neat side-effect of it is that it is "immune" to breakage by updates to the Fedora 9 kernel (a frequent event). Your file moving method, while clever, would have to be repeated after each kernel update.