I don't have a direct answer to your question, but here is the howto I have been using twice, with good results: http://www.howtoforge.com/software-raid1-grub-boot-fedora-8 After installing grub to the other disk, did you update your grub.conf accordingly? Terv. Jussi On 23.7.2010 11.12, Wessel | Postoffice wrote: > Hi All, > > I'm currently trying to install centos 5.4 x86-64bit on a raid 1, so if > one the 2 disks fails the server will still be available. > i installed grub on /dev/sda using the advanced grub configuration > option during the install. > after the install is done i boot in linux rescue mode , chroot the > filesystem and copy grub to both drives using: > grub>root (hd0,0) > grub>setup (hd0) > grub>root (hd1,0 > grub>setup (hd1) > grub>quit > > then reboot, but is still get the error : disk boot faillure, insert > linux install disk. > does anyone now what i'm doing wrong? here is a copy of my partition scheme. > > Disk /dev/sda: 251.0 GB, 251000193024 bytes > 255 heads, 63 sectors/track, 30515 cylinders > Units = cylinders of 16065 * 512 = 8225280 bytes > > Device Boot Start End Blocks Id System > /dev/sda1 * 1 38 305203+ fd Linux raid autodetect > /dev/sda2 39 675 5116702+ fd Linux raid autodetect > /dev/sda3 676 30515 239689800 fd Linux raid autodetect > > Disk /dev/sdb: 251.0 GB, 251000193024 bytes > 255 heads, 63 sectors/track, 30515 cylinders > Units = cylinders of 16065 * 512 = 8225280 bytes > > Device Boot Start End Blocks Id System > /dev/sdb1 * 1 38 305203+ fd Linux raid autodetect > /dev/sdb2 39 675 5116702+ fd Linux raid autodetect > /dev/sdb3 676 30515 239689800 fd Linux raid autodetect > > Disk /dev/md1: 5239 MB, 5239406592 bytes > 2 heads, 4 sectors/track, 1279152 cylinders > Units = cylinders of 8 * 512 = 4096 bytes > > > Disk /dev/md0: 312 MB, 312410112 bytes > 2 heads, 4 sectors/track, 76272 cylinders > Units = cylinders of 8 * 512 = 4096 bytes > > > Disk /dev/md2: 245.4 GB, 245442281472 bytes > 2 heads, 4 sectors/track, 59922432 cylinders > Units = cylinders of 8 * 512 = 4096 bytes > > > Regards, > > Wessel -- Jussi Hirvi * Green Spot Topeliuksenkatu 15 C * 00250 Helsinki * Finland Tel. +358 9 493 981 * Mobile +358 40 771 2098 (only sms) jussi.hirvi at greenspot.fi * http://www.greenspot.fi