>I thought to have tested this a while ago but I guess not. Ok... >I have a Centos 5.3 system (call its SYSA) software raid 0, 2 disks. So a strip? Did you mean Raid 1 (Mirror)? >I have an identical system (SYSB) else were, so I pull one of my >mirrors drives from SYSA and put it in SYSB as the only drive in SYSB. > >Upon but I get grub error. So I am sure you meant Raid 1, otherwise I suspect you see the futility in this? You need to install grub to both discs, whereas the installer just hits the first disc. In my MD Raid kickstart for systems like this I %post a grub script that works as you describe: # Install grub to both discs /sbin/grub --batch >/root/grub_install.log <<EOF root (hd0,0) setup (hd0) root (hd1,0) setup (hd1) quit EOF I actually use this on a dev system, I pull one of the two discs, boot and do my tests then rebuild from the outdated original, works well... jlc