[CentOS] /dev/sda

Tue Dec 6 20:59:30 UTC 2011
Lamar Owen <lowen at pari.edu>

On Tuesday, December 06, 2011 03:39:06 PM m.roth at 5-cent.us wrote:
> Ack! So I actually need to run grub-install, and do it for both; didn't
> know that (always had /boot as a plain vanilla primary partition)?!

If /dev/sdb doesn't have the stage1.5 in the first 60 or so sectors after the MBR (which it may not) then yes you'll need to re-run grub-install, or you can do a manual setup inside the grub shell.  I've seen a HOWTO out there, but its name (or other greppable info) escapes me at the moment.

The stage1.5 portion of grub is not located in /boot, nor is it located in any partition; it's between the MBR and the start of the first partition.  Copying the MBR is not enough if you have a stage1.5.

This is assuming that your boot is actually using a stage1.5 at all, and it might not be.