How to correct a mistake with a LUKS logical volume group

[purevw]

I created a volume group using a single 4TB drive with Yast and encrypted it. My intention was to add other drives to that group later as I freed up space to make drives available. What I found is that I am unable to add another drive to the existing group. I had hoped to make a JBOD setup within the volume group so that I could enter my passphrase a single time to unlock multiple drives. What my question is, is there a way to remove the 4TB drive from the group without destroying the 2.7TB of data already written to it so that I can start from scratch? I do have backups, but copying all that data again would be a real chore.

[nrickert]

You probably have to backup, then restore later.

You might have a confused view of LVM.

Strictly speaking, you don’t create a LVM and then encrypt it. Rather, you create an encrypted space (such as a disk partition), and then assign that to an LVM. The encryption comes before the LVM.

I use an encrypted LVM, but I have not tried adding additional space. My best understanding is that, for what you want to do, you would have to first encrypt your additional drive (giving a virtual device “/dev/mapper/crypto_name”. Then you would add that virtual device to your LVM.

It is also possible to do it the other way. That is, one can create an LVM on unencrypted space, and encrypt just the file systems within that LVM. But I don’t think that was what you wanted.

[hcvv]

@nrickert. I assume you wanted to type LVG in all the places where you to typed LVM. Just to avoid further confusion.

[arvidjaar]

@hcvv

I assume you wanted to type LVG

If we are going nitpicking - you probably mean PVG (or even simply VG)

[hcvv]

@arvidjaar

If we are going nitpicking - you probably mean PVG (or even simply VG)

Yes, and I have to make a further correction to myself. The first time nrickert typed LVM, he realy ment the Maneger (the software product). And he ment the Volume Group on the other places.

I do not know much about this type of encrypting, but as nrickert tries to exlain what to encript and what not, I assume that using the right terms like PV (disk or disk partition), VG (assembly of one or more PVs), or LV (parts of a VG) are crucial for people to understand this. At least for me and possibly also for the OP.

[purevw]

@nrickert

You probably have to backup, then restore later.

Strictly speaking, you don’t create a LVM and then encrypt it. Rather, you create an encrypted space (such as a disk partition), and then assign that to an LVM. The encryption comes before the LVM.

I use an encrypted LVM, but I have not tried adding additional space. My best understanding is that, for what you want to do, you would have to first encrypt your additional drive (giving a virtual device “/dev/mapper/crypto_name”. Then you would add that virtual device to your LVM.

It is also possible to do it the other way. That is, one can create an LVM on unencrypted space, and encrypt just the file systems within that LVM. But I don’t think that was what you wanted.

It is apparently not possible via Yast. Yast simply tells me that the volume group is full if I click on “add”. I suppose it would have to be done via a command line?