Support for multiple drives?

[TheDan64]

Is there any plan to support multiple hard drives? Would like to use this for encrypted NAS server setups

[r0b0]

With btrfs you can add raid setups after the installation. For example, here I installed debian on vda and later added vdb as raid0 for data (and raid1 for metadata):

root@debian13-vm:~# lsblk 
NAME     MAJ:MIN RM SIZE RO TYPE  MOUNTPOINTS
vda      253:0    0  20G  0 disk  
├─vda1   253:1    0   1G  0 part  /boot/efi
└─vda2   253:2    0  19G  0 part  
  └─root 254:0    0  19G  0 crypt /home
                                  /root/btrfs1
                                  /
vdb      253:16   0  20G  0 disk  

root@debian13-vm:~# fdisk /dev/vdb

Welcome to fdisk (util-linux 2.41).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table.
Created a new DOS (MBR) disklabel with disk identifier 0x20deef87.

Command (m for help): g
Created a new GPT disklabel (GUID: 4677FEAA-161D-4FEC-B292-08ECE5568EE0).

Command (m for help): n
Partition number (1-128, default 1): 
First sector (2048-41943006, default 2048): 
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-41943006, default 41940991): 

Created a new partition 1 of type 'Linux filesystem' and of size 20 GiB.

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

root@debian13-vm:~# lsblk 
NAME     MAJ:MIN RM SIZE RO TYPE  MOUNTPOINTS
vda      253:0    0  20G  0 disk  
├─vda1   253:1    0   1G  0 part  /boot/efi
└─vda2   253:2    0  19G  0 part  
  └─root 254:0    0  19G  0 crypt /home
                                  /root/btrfs1
                                  /
vdb      253:16   0  20G  0 disk  
└─vdb1   253:17   0  20G  0 part  

root@debian13-vm:~# cryptsetup luksFormat /dev/vdb1

WARNING!
========
This will overwrite data on /dev/vdb1 irrevocably.

Are you sure? (Type 'yes' in capital letters): YES
Enter passphrase for /dev/vdb1: 
Verify passphrase: 

root@debian13-vm:~# cryptsetup open /dev/vdb1 second
Enter passphrase for /dev/vdb1: 
Warning: keyslot operation could fail as it requires more than available memory.

root@debian13-vm:~# lsblk -f
NAME       FSTYPE      FSVER LABEL  UUID                                 FSAVAIL FSUSE% MOUNTPOINTS
vda                                                                                     
├─vda1     vfat        FAT32 ESP    1AF8-95B9                             786.2M    23% /boot/efi
└─vda2     crypto_LUKS 2     Debian 93b2c08e-6bf4-4910-965b-2e154ec00e7e                
  └─root   btrfs             Debian ebe97e2b-1acd-40ef-ac3d-cb981fcb36b9                /home
vdb                                                                                     
└─vdb1     crypto_LUKS 2            8e68cca6-7f59-45f4-82e7-99e8c02da536                
  └─second btrfs             Debian ebe97e2b-1acd-40ef-ac3d-cb981fcb36b9                

root@debian13-vm:~# systemd-cryptenroll /dev/vdb1 --tpm2-pcrs= --tpm2-device=auto
🔐 Please enter current passphrase for disk /dev/vdb1: •••••••••               
Warning: keyslot operation could fail as it requires more than available memory.
New TPM2 token enrolled as key slot 1.

root@debian13-vm:~# vim /etc/kernel/cmdline
rd.luks.name=8e68cca6-7f59-45f4-82e7-99e8c02da536=second rd.luks.name=93b2c08e-6bf4-4910-965b-2e154ec00e7e=root rd.luks.options=tpm2-device=auto rw quiet rootfstype=btrfs rootflags=compress=zstd:1,subvol=@ rd.auto=1 splash SYSTEMD_SULOGIN_FORCE=1

root@debian13-vm:~# dpkg-reconfigure linux-image-$(uname -r)
/etc/kernel/postinst.d/dracut:
dracut: Generating /boot/initrd.img-6.18.12+deb13-amd64
[...]
Installing kernel version 6.18.12+deb13-amd64 in systemd-boot...

root@debian13-vm:~# btrfs device add /dev/mapper/second /

root@debian13-vm:~# btrfs balance start -dconvert=raid0 -mconvert=raid1 /
Done, had to relocate 10 out of 10 chunks

root@debian13-vm:~# btrfs filesystem show /
Label: 'Debian'  uuid: ebe97e2b-1acd-40ef-ac3d-cb981fcb36b9
        Total devices 2 FS bytes used 4.75GiB
        devid    1 size 18.98GiB used 3.28GiB path /dev/mapper/root
        devid    2 size 19.98GiB used 3.28GiB path /dev/mapper/second

root@debian13-vm:~# btrfs filesystem df /
Data, RAID0: total=6.00GiB, used=4.55GiB
System, RAID1: total=32.00MiB, used=16.00KiB
Metadata, RAID1: total=256.00MiB, used=200.59MiB
GlobalReserve, single: total=18.20MiB, used=0.00B

I had to explicitly configure both drives in the kernel command line with rd.luks.name because they are needed for mounting the root volume. That was pretty much the only catch.

[TheDan64]

Thank you!! This is really helpful.

It probably still makes sense to support some common configurations in the UI? I think this is the sort of thing that's easy to mess up