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Change NVME LBA Size

Since we are about to deploy AnduinOS on a machine, and you may have a NVME SSD with a 4K LBA size, we need to change the LBA size to 512 bytes to make it compatible with AnduinOS.

This guide will walk you through changing your NVMe drive to use a 4K (4096 bytes) Logical Block Addressing (LBA) format. Please note that this procedure will erase all data on the drive. Make sure to back up any important information beforehand.

1. Install Required Tools

First install nvme-cli (and update your package list if needed):

sudo apt update
sudo apt install nvme-cli

2. Identify Your NVMe Device

List all drives to identify your NVMe device:

sudo fdisk -l

Confirm your NVMe device (often named /dev/nvme0n1, but could differ). You can also run:

nvme list

This should display details about your NVMe devices.

Check current LBA formats:

Check LBA Formats
nvme id-ns /dev/nvme0n1 --human-readable

Look for lines like:

LBA Format  0 : Metadata Size: 0   bytes - Data Size: 512 bytes - Relative Performance: 0x2 Good (in use)
LBA Format  1 : Metadata Size: 0   bytes - Data Size: 4096 bytes - Relative Performance: 0x1 Better

For some disks, it may show that not better format is available. It's only suggested to continue if you see a better format available.

In the example above, the drive has two LBA formats available. We want the 4K format, usually shown as lbaf=1.

3. Perform the Format Operation

Warning: The following command destroys all data on the NVMe device. Double-check the device name and ensure you have a full backup.

  1. Execute the format command:
sudo nvme format /dev/nvme0n1 --lbaf=1 --ses=0
  • --lbaf=1 selects the 4K LBA format.

  • --ses=0 performs a format without secure erase (faster). You can use --ses=1 for a more thorough erase if desired.

  • Wait for the format to complete. The device should now be in 4K mode internally.

4. Recreate Partitions and Filesystems (Using fdisk)

After formatting, the drive is blank and needs partitioning and a filesystem. Here’s how to do it with fdisk:

  1. Open fdisk on the device:
sudo fdisk /dev/nvme0n1

  1. Create a new GPT partition table:

    • Press g to create a new GPT partition table.

  2. Create a new partition:

    • Press n to add a new partition.
    • Accept default values (or adjust if you want a smaller partition).

  3. (Optional) Review partition layout:

    • Press p to print the current partition table.

  4. Write the partition changes:

    • Press w to write and exit fdisk.

  5. Create a filesystem on the newly created partition (example: ext4):

    sudo mkfs.ext4 /dev/nvme0n1p1

Your disk now has a single ext4 partition aligned and ready for use.

5. Verify the Result

Verify that your NVMe now uses a 4K LBA format:

nvme id-ns /dev/nvme0n1 --human-readable

Look for the active LBA Format:

LBA Format  1 : Metadata Size: 0 bytes - Data Size: 4096 bytes ...

If you see 4096 bytes as the data size, then the drive is using 4K blocks.

6. Summary

  • Backup all important data beforehand.
  • Use nvme format with the correct --lbaf option to switch to a 4K LBA format.
  • Re-partition the drive using fdisk, selecting GPT and creating at least one partition.
  • Format the partition with a suitable filesystem (e.g., ext4, xfs, etc.).
  • Confirm with nvme id-ns that the LBA format is set to 4096 bytes.

You now have your NVMe device configured to 4K LBA, which can provide better performance for many workloads.