Unable to create One Big RAID 10 prior than Centos ?

  • Okay here is the scenario, I can ofcourse create this after Centos gets installed, but I want to do it prior, I reckon the superblock can provide all the details and information for the OS.

    Using Parted Magic this works 100% and the that OS created the RAID array and was able to see it and mount it correctly everytime.

    However with Centos I load up the installer, I switch to terminal prior when I see the installer screen, and I can create successfully RAID devices with the mdadm tool, but Centos installer is not seeing it no matter what.

    I was able to mount it under /mnt/raid 10, but I had to create that mountpoint manually, when I do normal mount command it states entry is not found it /etc/fstab and even If i created entry this is live OS session if I rebooted it wont be there ? Also under /mnt I dont see the 4 disks I recall seeing 2 folders system installer and another one.
    the devices are under /dev/ folder. I see /dev/sda and /dev/sdb and /dev/sdc/ and /dev/sdd also /dev/md0 which is the RAID i created but it is not allowing me to install on it.

    Logically am I doing something wrong trying to do the mdraid prior than the OS ?

    The easy way out is install the O.S on its own disk (without RAID) then create RAID with the other drives, but this way I will need 5 storage disks and not 4.

    The issue is basically when I go to the Centos installation and click on Disks it shows me the 4 disks separated.

    This is not production environment, testing and learning Virtualbox

    Thanks in advance.

  • Software RAID can never exist until the OS is loaded. So you always have to boot from a non-RAID partition that handled booting.

  • @scottalanmiller

    I think I got it working with Ubuntu LTS 16.04.2 currently installing the system will see how it goes, however it does make sense that OS needs to be in-charge of this.

    2_1493037076747_2017-04-24 15_30_54-Centos RAID 10 KVM [Running] - Oracle VM VirtualBox.png 1_1493037076747_2017-04-24 15_30_35-Centos RAID 10 KVM [Running] - Oracle VM VirtualBox.png 0_1493037076747_2017-04-24 15_30_22-Centos RAID 10 KVM [Running] - Oracle VM VirtualBox.png