Arch Linux

No

Member

Registered: 2010-11-13

Posts: 44

[SOLVED] DM_Crypt+LVM, changing passphrase

I had no idea where to post this but it does have to do with protection/security. I am not sure if it is even possible. I have my swap, / encrypted. Boot is not. I want to change the passphrase, if I can. I set this all up manually during installation.  I tried a few things online/scroogle search and nothing. So I thought I would start over here at this forum and see what others thought and if there is a way to do it. Here is what I did.

______________
sda1 boot ext2
sda2 dmcrypt
          /dev/mapper/crypt  dmcrypt->lvm-pv
          /dev/mapper/crypt+ lvm-pv->lvm-vg
          /dev/mapper/pool   lvm-vg(pool)->lvm-lv
          /dev/mapper/pool   lvm-lv(swap)->swap
          /dev/mapper/pool   lvm-lv(root)->ext3
_______________

I am somewhat new to this. I took a break from Arch for a bit and distro hopped around. All the ones I tried that had lvm encryption where much easier to set up and I never thought about changing the passphrase before.

So any thoughts?

(Looking at past posts here and other places I always seem to be trying something new or different, I love Linux. I think that is why I came back to Arch. You start with less and can mold your os the way you choose.)

Last edited by No (2011-06-30 23:44:47)

seiichiro0185

Member

From: Leipzig/Germany

Registered: 2009-04-09

Posts: 226

Website

Re: [SOLVED] DM_Crypt+LVM, changing passphrase

I assume you used LUKS Encryption with cryptsetup. If so you can change the passphrase by using the command

cryptsetup luksChangeKey /dev/sda2

Im not sure if this will work from a running system, I would suggest doing this from a LiveCD/LiveUSB. More Options and infos about the command can be found in man cryptsetup

---

My System: Dell XPS 13 | i7-7560U | 16GB RAM | 512GB SSD | FHD Screen | Arch Linux
My Workstation/Server: Supermicro X11SSZ-F | Xeon E3-1245 v6 | 64GB RAM | 1TB SSD Raid 1 + 6TB HDD ZFS Raid Z1 | Proxmox VE
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No

Member

Registered: 2010-11-13

Posts: 44

Re: [SOLVED] DM_Crypt+LVM, changing passphrase

I assume you used LUKS Encryption with cryptsetup. If so you can change the passphrase by using the command

cryptsetup luksChangeKey /dev/sda2

Im not sure if this will work from a running system, I would suggest doing this from a LiveCD/LiveUSB. More Options and infos about the command can be found in man cryptsetup

I tried it through my Arch install, I didn't have to boot into a live cd and this worked nicely. I tried similar things before but they had extra commands in it and it didn't work. But this worked perfectly and it was very easy. Thank you.

Last edited by No (2011-06-30 17:09:51)

stqn

Member

Registered: 2010-03-19

Posts: 1,191

Website

Re: [SOLVED] DM_Crypt+LVM, changing passphrase

Edit: nothing, sorry . (Should be [SOLVED], not <SOLVED>, though.)

Last edited by stqn (2011-06-30 22:08:59)

No

Member

Registered: 2010-11-13

Posts: 44

Re: [SOLVED] DM_Crypt+LVM, changing passphrase

Edit: nothing, sorry . (Should be [SOLVED], not <SOLVED>, though.)

Good point. I just like to be different  ;-) But for the sake of less confusion I will do it with the [  ]   :-)