Issue with Raid-10 on existing Almalinux installation

rafathossain

Hi,

I was trying to do raid-10 on an existing Almalinux installation with 4 NVMe drives.

My OS is currently installed in /dev/nvme0n1 drive. Partition scheme is as below:

nvme0n1     259:2    0 953.9G  0 disk 
├─nvme0n1p1 259:4    0   500M  0 part /boot/efi
├─nvme0n1p2 259:5    0     1G  0 part /boot
├─nvme0n1p3 259:6    0     8G  0 part [SWAP]
└─nvme0n1p4 259:7    0 944.4G  0 part /

I created raid array manually in degraded mode by marking the primary disk as missing, so that I can add the other disk after running the OS from raid array.

Then copied all the conents of the /boot, /boot/efi and / to the newly created raid arrays.

Then I copied the blkid and updated the fstab with the proper uuid.

But when I do the reboot, the OS does not load from the raid array. I think I am missing some steps after the raid configuration. May be grub config? Or bootloader installation?

What should be the proper steps to achieve raid-10 on existing installation?

davide

If Grub sees the md block device and the kernel image within it, either the initramfs needs the raid kernel module, or the kernel needs the raid module built-in, or the 'root' kernel parameter passed by Grub is wrong. The latter needs to be something like:

/boot/vmlinuz-5.17.5 root=UUID=41bff933-4fca-4586-befb-679f06842d49

This is my garbled and garbaged Grub config. I cannot read anything in it. Fuck Grub.

jackb

I'd recommend having boot and boot/efi as raid1 instead of raid10. That way it can load off any disk without depending on the raid module.

rafathossain

@davide said:
If Grub sees the md block device and the kernel image within it, either the initramfs needs the raid kernel module, or the kernel needs the raid module built-in, or the 'root' kernel parameter passed by Grub is wrong. The latter needs to be something like:

/boot/vmlinuz-5.17.5 root=UUID=41bff933-4fca-4586-befb-679f06842d49

This is my garbled and garbaged Grub config. I cannot read anything in it. Fuck Grub.

In which file, do I need to edit the entry?

After configuring the fstab, do I need to run grub2-mkconfig -o /boot/grub2/grub.cfg?

I am a bit confused in this part. Basically after configuring the fstab entry, what are the steps to be completed?

davide

The kernel needs the root parameter set to the block device or UUID of the filesystem you want it to boot off. I have no clue how this is done in Grub2; I would start from /etc/grub.d/README for not knowing any better.