Pro Max 16 Plus MB16250, RAID 1 setup?

Thats certainly going to be a tough one to answer. I'd recommend posting this on the Ubuntu forum as more users are likely to have the know how there. 

https://discourse.ubuntu.com/

Hi

Not a fan of ubuntu, however ....

Dell-specific notes

• If the Dell BIOS SATA/Storage mode is set to Intel RST or RAID On (firmware RAID), you can still use mdadm; vendor RAID can complicate detection, so software RAID is usually simpler for Ubuntu.

• If you prefer hardware/firmware RAID (PERC or Intel RST), use Dell’s controller utility to create the virtual disk before OS-level changes, but vendor RAID often requires Windows tools or drivers and can be harder with Ubuntu; for most Ubuntu setups mdadm is preferred.

Risks and backups

• This process manipulates disks and will risk data loss if steps are mistaken; take a full backup or image before starting.

• Work from a live USB to avoid locked filesystems and to safely install mdadm and update initramfs.

Short answer: Use Linux software RAID (mdadm) — create a degraded RAID1 on the new drive, copy the existing Ubuntu system to the array, update the initramfs and GRUB on both disks, then add the original disk to finish the mirror.

Why this approach

• It avoids a full reinstall and works on Dell machines regardless of vendor RAID firmware, which can be problematic for Linux.

• Using mdadm (software RAID) gives the best compatibility and control under Ubuntu.

High-level steps (one pass/path you can follow)

1. Prepare and install mdadm

• Boot a live USB (Ubuntu desktop/server) so root filesystem can be modified offline.

• Install mdadm: sudo apt update && sudo apt install mdadm.

2. Create RAID device in degraded mode on the spare disk

• Create matching partitions on the new disk (EFI, swap if used, root) with the same types and sizes as the installed disk (use gdisk/parted/sgdisk).

• Create the RAID1 device(s) using one device and one missing slot, for example:

  • sudo mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdXn missing

  • Repeat for /boot/efi if you want the EFI on a mirrored device (or use separate EFI on each disk).

3. Create filesystems and copy the system

• Make filesystems (e.g. mkfs.ext4 /dev/md0) and mount them under /mnt/newroot.

• Copy / to the RAID device using rsync to preserve permissions: rsync -aAXH --exclude=/proc --exclude=/sys --exclude=/dev/pts --exclude=/mnt --exclude=/tmp /mnt/oldroot/ /mnt/newroot/ (adjust source/destination paths).

4. Mount virtual filesystems and chroot

• Mount /dev, /proc, /sys, and bind-mount /run, then chroot into /mnt/newroot.

5. Configure mdadm, initramfs, and GRUB in chroot

• Install mdadm inside chroot and update config: mdadm --detail --scan >> /etc/mdadm/mdadm.conf; update-initramfs -u -k all.

• Install GRUB onto both disks (for BIOS and UEFI, install appropriately): grub-install /dev/nvme0n1; grub-install /dev/sda; update-grub. This ensures either disk can boot.

6. Reboot and test boot from new RAID device

• Reboot and ensure the system comes up from the RAID array. Check /proc/mdstat and mdadm --detail /dev/md0.

7. Add the original disk to the array

• Once booted on the RAID, partition the original disk to match and then add its partitions to the md arrays: mdadm --add /dev/md0 /dev/oldrootpart. Monitor resync with cat /proc/mdstat.

8. Finalize

• Save mdadm config (sudo mdadm --detail --scan > /etc/mdadm/mdadm.conf and update-initramfs again), ensure fstab uses /dev/mdX or UUIDs for the RAID devices, and confirm GRUB is installed on both disks.

AFAIK, the only "Intel RAID" ever available was Intel-RST. That is now depreciated and only worked in Windows anyway.

 

Your NVMe SSD should be "crazy fast" even in Ubuntu.

Instead, use the other drive to hold your Daily (or hourly) Differential or Incremental backup disk-images. Those work with Daily or Weekly Full-Images.