On 2/28/07, Mário Gamito <gamito at gmail.com> wrote: > Hi, > > I had this hard time installing a server with RAID 1 by software. > I always got an error from GRUB and no booting. > > So, i've installed CentOS 4.4 normally in only one disk. > > Question is: is it possible now to make a RAID 1 by software with the other > disk ? > > If so, how ? > > I'm completely lost here. > > Any help would be appreciated. Yes, though I don't think you can just directly convert your non md devices to md devices. I could be wrong, and if so someone merrily show me the error of my ways. Now here is what I would do: 1) Create the same partitions on the other disk (even you swap partition), except set their type to autoraid (0xfd). 2) Now using mdadm (read man page) create your md devices, but each with only one member comming from the newly created partitions. 3) Activate the md devices. 4) Now if your using LVM, change the appropriate md devices into pv's and then create your volume group(s) and logical volume(s). 5) Lay down filesystems on lv(s) and/or the md(s). 6) Using tar or cpio, copy the files from your running systems filesystems to the ones that are now sitting md devices (if only indirectly through lvm on top of md's). 7) Setup grub on the running system (i.e. not the drive you have participating in md devices) to boot the kernel off of the md device your kernel is in, and to have that kernels root filesystem be from the root filesystem sitting on an md device. 8) Now reboot the system; this shoudl boot from the md devices. 9) Using fdisk change the non md device partitions to type autoraid. 10) Now add this partitions to the md devices as members of the raid sets. 11) At this point you should have the contents of the second disk syncing to the first. Let this finish (you can monitor it by looking at /proc/mdstat). 12) After this edit the grub.conf again to use the md devices. 13) Install the grub boot loader on your second disk also. As an aside, the grub side is really the trickiest part of this, because though you want to boot the kernel off of the other disk after you've created you initial md devices in degraded mode, you are actually going to boot grub from the first disk, and then aquire your kernel from the second. At the point the disks are synced, then you will be back to your old grub configuration, because you haven't changed that on the raid side (though you could I suppose), and so you have to rechange the grub configuration again. Anyway this is a rough outline. I have purposely avoided giving you specific commands and such, as the reading of the man pages is your responsibility. Also, there are places in here where if you do the wrong thing your system is toast, and your remedy will likely be to re-install. So YMMV and good luck...james > > Warm Regards, > Mário Gamito > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > >